Moses Ludel

All good points, Megatron, each deserves an explanation, so here we go...I'll begin by sharing that I ran a four-wheel alignment rack at a GMC truck dealership in the mid-'80s, the era of both beam front axle 4x4s and IFS 2WD and 4WD front ends. For fifteen years prior to that, I had been doing alignment with far less equipment than that new Hunter four-wheel, electronic light beam rack. Fifteen years after the dealership stint, I taught wheel alignment at the adult vocational training level and merged my varied equipment experiences, which reflect in what I'm now sharing. It's great to use precision four-wheel alignment equipment. However, "computer" alignment equipment is also limited in many ways. For example, you describe aftermarket wheels, suspension and tires, and you're right, of the three (assuming the suspension kit is as adjustable as yours), the wheel offset is the most critical modification. Because your truck falls outside the OEM guidelines built into the software for modern alignment equipment, many shops will avoid doing your truck's alignment. Reasons for refusal include "liability", "unpredictable results" and "possibility of abnormal tire wear"—regardless of the alignment procedure. In many cases, the shop simply doesn't know what they can do to address or compensate for your modifications...After all, this is the era of plug-and-play. Follow the flow charts or stare at the computer screen or scanner. Wait long enough, and maybe an answer will materialize...That's not going to happen here! For now, let's suspend judgment about why your truck and millions of other 4x4s are in this predicament. You've installed all of this hardware, and it's time to make the vehicle track as safely as possible—and for the tires to last. As for front axle lateral alignment, your adjustable track bar is a real asset. Alignment does reference from the rear axle, and for good reason. The term "thrust" is just what it sounds like: The rear axle on a RWD vehicle is the traction point, pushing the frame and the entire vehicle forward from the rear. Unless you're driving backward, your rear-drive truck requires the front axle to align squarely under thrust. (Thus the term "thrust alignment"!) The axles must be square, in any case. To illustrate, draw a line forward and perpendicular to the centerline of the rear axle. This follows the driveline in approximate terms—unless the driveline is offset like with a side-drive transfer case. This line of force, aimed forward and perpendicular to the rear axle, becomes the reference point for the front axle's position. The front axle ends up parallel to the rear axle, which is simple to visualize on beam axle trucks like our Ram 3500 models. The front axle must also align sideways or laterally, the reason for your adjustable track bar. Whether the frame is perfectly square or not, if the front axle is parallel to the rear axle (plane view from the top), and if the axles center laterally with each other, you can align the truck's front end. The frame should be square, though, because an out-of-square frame would place the springs, suspension arms and steering linkage at odd angles with the axles. So, let's start with a square frame, no collision damage, and a rear axle that sets squarely in the truck. It's much easier with our leaf sprung, beam rear axle: The centering points for the rear axle are simply the leaf spring center bolts and the axle's spring perch holes—plus any spacer block alignment holes or pins. Rear axle in place, you can use the string-in-diamond method for setting the beam front axle's position for both parallel to the rear axle and laterally on center. I used the string method for two illustrated how-to articles at the magazine: my Jeep XJ Cherokee 6-inch long arm installation at the "Jeep XJ Cherokee & MJ Comanche 4WD Workshop" (see the left panel menu) and also the Jeep TJ Wrangler Rubicon Full-Traction Ultimate 4-inch lift. The XJ Cherokee is similar to our Dodge Ram trucks with link-and-coil front suspension and leaf springs at the rear. Both Jeep vehicles have beam axles front and rear. Critical to a string-in-diamond beam axle alignment is finding precise reference points at each of the axles. You must have a reference point at each side of the front axle that is truly equal distance from the axle's centerline. The rear axle on our trucks is simple: Use the leaf spring center bolts as the rear reference points. On a Jeep TJ or JK Wrangler, there are matching suspension points that are equidistant from the rear axle's centerline. The front axle should align with equal string lengths to the rear axle, measured in cross or "diamond". This means measuring from the front axle's left side reference point to the right rear spring center bolt, then from the front axle's right side reference point to the rear axle left side spring center bolt. This measurement must be very accurate. Even 1/16"-1/8" variance can make a difference. If there are obstacles under the chassis that prevent an accurate measurement, you may need to relocate your reference points or even make "extensions" from the reference points to below the obstacles...For these measurements, you can have the axles suspended to full drop, which may help the string lines clear the transfer case skid plate, the exhaust or any other objects in the way. Be creative. It's crucial that your four reference points reflect equal distances from the center of each beam axle outward to each axle's reference points. Strings then measure in cross between the front and rear axle reference points. Again, the end game here is to have the axles parallel and tracking in line with each other. When the front axle is offset laterally, one way or the other, we call this "dog tracking". Note: Don't be confused if one axle's track width is actually slightly wider than the other axle with the wheels in place. Some trucks (G.M. beam axle 4x4s come to mind) were designed this way, typically with the front axle slightly wider than the rear. I won't digress into "why" this was the design, simply know that if your reference points match side to side on each axle, and if you run the string lines in cross to matching points at the opposite axle, you will determine both the square and lateral alignment of the two axles. Checking for square with two strings-in-cross is a simple function of geometry. If anyone is having difficulty understanding the principle, draw a perfect square on a piece of paper; now draw an "X" from opposite corners, intersecting at the middle. Measure the length of each "X" line. It will be equal. If you now use a rectangle instead of a square, the results will also be two equal length, intersecting lines. Play with this, and then transfer the "X" lines to your truck's chassis: On your long wheelbase Dodge Ram 3500 truck, the beam axles represent the short ends of a rectangle. The most elaborate "4-wheel" alignment machine will not produce any more accurate results than doing a string line test properly. Once you get the axles square, you can concentrate on a front wheel alignment. This, as you say, is not rocket science, and it's even easier with a beam front axle. Camber, in particular, is factory pre-set on a beam axle. Camber measurement indicates the degree to which the axle beams, steering knuckles and ball joints are in alignment. As you mention, you can make camber corrections with off-set ball joints, or eccentric ball-joint seats, and a source for such parts is Specialty Products Company. Caution: I am against "bending" beam axles to correct slight camber issues unless a racing, weld-on truss is part of the straightening process. (Be aware, too, that welding on a truss is a good way to warp an axle and alter camber!) Consider the axle tube and center section materials plus the original stress that caused the axle to bend. There are metallurgical changes that take place with cold or hot bending. If you need to correct for a slightly bent or out-of-spec axle beam, use offset ball-joints or eccentric ball-joint seats. Make sure the bend did not stress-fracture the axle pieces. Toss out the axle housing if in doubt—you can transfer internal pieces and add-on goodies to a new housing. (See the magazine's many axle rebuilding articles and the HD videos on axle setup.) Be aware that beam front axles come from the factory with +/- camber often slightly beyond the factory recommended camber degree range. I have seen this on Dana Jeep front axles, typically at the short beam side with more factory welding. An extra 1/8 to 1/4-degree camber at one side is not earthshattering and likely was acceptable during OEM axle assembly and installation. This will not impair vehicle handling and has negligible effect on tire wear if you rotate your tires on time. If you are adjusting caster and camber with offset ball-joints or eccentric ball-joint seats, bring both the caster and camber within their recommended degree ranges. To answer your questions about "do-it-yourself" alignment, go no further than these three features that I've done at the magazine. They each get brisk traffic, addressing alignment goals with inexpensive solutions for doing your own alignment work. First is the ‘DIY’ feature on a beam front axle wheel alignment. This is a useful article for understanding the principles of front wheel alignment as well as a 'how-to' on using an affordable SPC Off-Road Fastrax 91025 gauge kit designed for tires to 44" diameter. Click here to see this DIY how-to and equipment article. For those on a shoestring budget, a single gauge kit will do. You can even improvise on the need for turn plates. SPC suggests using plastic sheeting beneath the front tires for a slip surface. On a beam axle, you can unload the weight slightly with the use of two floor jacks, raising the weighted axle evenly and just enough to take the heavy load off the front wheels and tires. This provides easier wheel turning. There is also a photo closer to home, my Dodge Ram 3500 4x4 alignment after installing the Mopar lift kit. Here, I purchased inexpensive front turn plates ($100 for the pair!) from Gil Smith Racing at New York. Gil is a personable family guy, and these plates do the job despite the massive front end weight of the Cummins engine, 9.25" beam axle and 500 pounds of Warn bumper with M12000 winch and stainless wire. For the Dodge Ram alignment, I added a second Fastrax 91025 alignment gauge kit from SPC to make toe setting easier and quicker. This way, you can use the winged braces and separate gauges at each side of the truck during the alignment procedure. This eliminates the need to swap a single gauge set from one side to the other. Last, but surely not least, is the HD video walk-through of alignment on a Jeep TJ Wrangler Rubicon. You'll like this for both a visual orientation and added quips about the process. In this HD video, I do use the double alignment gauge sets from SPC and the Gil Smith turn plates. You’ll see how this speeds up the process. Some additional pointers on doing your own alignment at this level: 1) make sure the floor is flat in both directions or compensate when taking the measurements with the bubble gauges, 2) make sure the turn plates are thin (like the Gil Smith type) or if you spring for more commercial type turn plates (available from several sources, do a Google search under "wheel alignment turn plates"), make sure you raise the rear of the truck to compensate for the turn plate height at the front. Even with a 140.5" or longer wheelbase, a sloping or leaning truck will throw off your camber and caster readings with the SPC 91025 bubble gauges...If you want to add a touch of professionalism, purchase a pair of rear slip plates from Gil Smith Racing that will enhance the work and raise the truck's back end to match the front turn plates. As you mention, always save the toe-in setting for last. Camber and caster angle must be right, with the vehicle setting at static (curb) height on the ground, before setting toe. I use factory toe-in and caster angle settings, and the Dodge Ram handles very well. And, yes, caster is important, this and steering axis inclination (SAI) are what return the front wheels to center after coming out of a corner. The surest sign of too little caster angle is a vehicle that requires turning the steering wheel back to center after a turn. I'm at 4-degrees positive caster on the Dodge Ram 3500, closer to 7-degees positive on the XJ Cherokee. More can sometimes be better for off-pavement turning radius; however, factory specs are the best for normal tire wear and handling in general. I mentioned another specification that is of concern during alignment: steering axis inclination (SAI). We can go into this if you want, but the important thing to note for DIY alignment purposes is that strange caster and camber angle readings over the full turning arcs (illustrated in the XJ Cherokee alignment how-to article and shown in the TJ Wrangler HD video coverage) are an indication of a bent steering knuckle on a later beam axle 4x4 or a bent spindle on 2WD and vintage 4WD vehicles. On alignment equipment that will identify SAI error, if all measurements are correct and SAI is off, we inspect the steering knuckle, spindle or unit bearing hub for damage. Make sure any strange readings are not from bad steering knuckle ball joints or worn wheel/hub bearings! Better yet, inspect for ball joint, wheel bearing and unit hub bearing wear before attempting the alignment. Check steering linkage for loose joints, too. This is ground school, we can go from here. As a light- and medium-duty truck fleet mechanic in the late 'sixties, I began aligning my own beam axle Jeep CJ3A and vintage '55 Ford F100 at home. On these vehicles, toe-in could be set with nothing more than a tape measure. If you do wheel alignment with turn plates, the steering linkage and suspension will be unloaded, and the measurements will be that much more accurate. Add rear wheel slip plates and Fastrax gauges, and you can emulate a "pro" alignment! Even on the vintage 2WD and 4WD fleet trucks with beam axles, I did quick, rough-in beam axle wheel alignments with nothing more than a tape measure or a portable, adjustable "toe bar". Floor jacks were placed evenly under the axle at each side. I would lift the axle beam just enough to "unload" the wheels and tires. Before setting toe, I made sure the wheel bearings and kingpin bushings or bearings were in good shape and adjusted properly. Tape measure alignments on the trail are often necessary when someone bows a tie-rod on a tall rock or snaps a tie-rod in half. A Ready Welder tie-rod repair at Moab's Rose Garden is just one place where your tape measure alignment skills would be popular. This can get a vehicle home from the trail and tracking down the road safely to a wheel alignment shop. When using just a tape measure for toe-set, make sure you follow the tread pattern closely at the front and rear midline of the tires. When using turn plates to unload and center up the steering linkage and suspension, it helps to bounce the front end. Push down on the front bumper a few times—the bumper is conveniently located at waist height on your Mega Cab! If necessary, use a pair of floor jacks under the beam front axle to take weight off the wheels and tires, then lightly rock the steering wheel at its center position before setting the front tires and steering wheel to straight ahead. This will unload the steering linkage for more accurate alignment settings. When using a tape measure only (not the Fastrax 91025's wing arms), always measure matching tread points. Measure as close to the midline (3 and 9 o'clock) of the tires as possible. Avoiding obstacles is sometimes difficult, but midline of the tires is preferred. Always set toe-in, followed by centering up the steering wheel. You center the steering wheel by adjusting the steering linkage sleeves—never by removing the steering wheel and repositioning it! Caution: The steering wheel spokes are factory set to align with the center or “high” point of the steering gear in the straight ahead steering position. Bring the front wheels into alignment with the centered steering gear and steering wheel—not the other way around! If the steering wheel has been repositioned from factory, find the precise center point of the steering gear. Position the steering wheel there before aligning the front wheels to straight ahead. This also applies when making fine steering wheel position changes after an alignment: Adjust the steering linkage sleeves, do not reposition the steering wheel! Always check toe-in again when you center the steering wheel. To illustrate how well you can do a 4-wheel alignment with strings, a tape measure, a common spirit level and a protractor, I installed the Full-Traction Ultimate lift kit on the Jeep TJ Wrangler Rubicon in just that way! The job began with the vehicle on my hoist and as level/parallel to the ground as possible. I placed a pair of adjustable tripod stands beneath each axle and raised the vehicle straight up, just enough to install the lift kit. The axles remained on the stands with cables and other chassis attachments still in place. After installing the kit, including a bevy of adjustable link arms and a unique rear tri-mount suspension system, I used the string method to square the axles. The rear axle location, fortunately, was fixed by the kit’s design, so this became the reference for making everything square with the frame. The approach was similar to the rear leaf springs and center bolts on our Dodge Ram 3500 trucks. In our case, the rear springs and axle spring perches locate the rear axle squarely at the frame. I set the caster with a quality bubble level and a 180-degree, indexed protractor. I set toe-in with vehicle weight on the axles and tripod stands, using a tape measure fore and aft (as close to 3 and 9 o'clock as practical) at the front tire midlines, keeping the tape as level and parallel to the floor as possible. In my view, this was all just a preliminary, rough adjustment. The next stop was a friend's shop with a $40K alignment rack capable of 4-wheel "thrust" alignment. On the alignment rack, to everyone's surprise, the entire suspension system took only one-half turn of one threaded link arm tube to be fully square! Caster was on, camber (non-adjustable on a solid beam axle) was okay, toe-in and centering of the steering wheel were just routine, slight adjustments. Caster angle was within spec and did, as you describe, provide an acceptable angle for the front/pinion U-joint flange. With a double-Cardan (CV) joint at the transfer case, there is some leeway on this front axle pinion joint angle, and the compromise is between caster angle and U-joint angle. Like you comment, caster usually wins if you want the vehicle to steer correctly! For modified trucks with suspension lifts and oversized wheels and tires, there are two very important considerations for handling. First, the aftermarket wheels' offset and the tire diameter must provide the right intersect point with the ground. This is the “scrub radius”. Visualize the front wheels pointed straight ahead. Draw a line through the ball-joint stud centerlines and observe where that line intersects the tire tread at the ground. This point must be similar to the OEM wheel/tire intersection point, or you will swing the tire on an odd arc during turns, resulting in strange handling and premature tire wear. Scrub radius impacts tire wear as well as handling. Secondly, consider the arc of radius and caster angle changes as the front suspension (link arms in your case) rise and set. Arc of radius is why we do long-arm kits for dramatic lift. When we increase suspension travel, short arms exaggerate the caster angle changes as the suspension extends and compresses. Long link arms are the solution for increased suspension travel. Longer arms will create less caster angle change over the suspension and axle’s arc of travel—or radius. Simply put, you can set the caster at static/curb weighted chassis height, and the caster angle does not vary excessively as the link arms move up and down with the axle. When buying an aftermarket suspension lift kit or bigger/wider wheels and tires, consider these issues. In looking at your Mega Cab components, I really like the stamina and quality of the aftermarket joints, link arms and drop brackets! What you want at the end of the day is suspension that behaves as well as or better than OEM engineering—yet with the lift and tires you desire. Going beyond “looks”, the goal is to understand the demands and dynamics of vehicle suspension and handling. Doing your own wheel alignment is a good start. As for the rear axle, the usual concern is pinion and driveline angles for U-joint survival. Within reason, you can rotate the axle housing for pinion angle change without affecting vehicle handling, as the rear drive axle’s shafts are not sensitive to caster. (If we were talking about a front wheel drive car or an IRS/AWD car, there would likely be provision for adjusting rear wheel caster, camber and even toe-set.) For our trucks, tall lift blocks at the rear leaf springs can create some issues, mainly traction and spring windup related. So, you might skip the visit to the local 4-wheel alignment shop and the brief Car and Driver read—likely just long enough for the tech to discover that specifications for your lifted and modified '06 Dodge Ram 4x4 Mega Cab are nowhere to be found in the alignment machine's software program. As an option, consider the SPC Off-Road 91025 alignment equipment...Two kits work even better than one! Used properly, this accurate, portable SPC setup can help you dial your front end alignment for both safety and good tire life. Bubble caster and camber gauges were an automotive industry standard for at least sixty years prior to light beam, infrared, RF and laser alignment equipment. I entered the service and repair industry when we were still called "mechanics", and breaker point ignitions were the norm. Smaller shops used floating caster/camber bubble gauges that fit magnetically to the end of front wheel hubs! Professionally, I've spun wrenches all the way into the contemporary electronic fuel-and-spark management "technician" era. Electronic, beam four-wheel alignment equipment has been in vogue for more than three decades now...I find it advantageous to have walked in both worlds. Beyond alignment, make sure that the wheel offset and tire diameter add up to a safe and tolerable "scrub radius”. As an alternative to Car and Driver, sift through this Wiki info about scrub radius and SAI. When you widen the wheel rims, you can only go inward so far. (Rotors, calipers and hubs limit the inward wheel position.) For that reason, wide rims almost always offset to the "negative" direction or outward. If there are wheel backspacing choices, match up the wheel width, backspacing and tire diameter wisely! The concern here is the scrub radius. We lift our vehicles and mount oversize wheels and tires for a variety of reasons. In the end, we get to make the handling and safety corrections that these modifications require. Routine tire rotation is always essential, even more so when scrub radius and arc of radius get compromised. Once you dial the front end alignment to the best point possible, watch for ball-joint wear, wheel bearing or hub bearing wear and any tire issues. This can sometimes be the price for a lift and oversized tires. We can, however, reduce, minimize or even eliminate that risk and expense! Moses

Actually, you would make an excellent travel journalist, biggman100! You make Upstate New York very appealing and real to those of us from out of the area...While the West gets kudos for places like the Rubicon Trail, Moab, the vast deserts, tall mountain ranges and wild horses, what you describe is the essence of why we four-wheel and camp outdoors: enjoying the woods, water recreation and family time—wherever Nature calls! Apparently, the call is clear from Upstate New York! Wow, this is a great place for parents to share with their kids. Actually, any outdoor enthusiast would enjoy traveling here, sounds like year round recreational opportunities! I trust other members and guests at the forums will get the message: Upstate New York has great outdoor offerings! We have Jeep 4x4 friends at the White Plains/Sommers Area who introduced us to Cold Springs, the Hudson River and the many wooded and stream-fed areas within a stone's throw from New York City. The Fall is incredibly colorful, drawing canoeists, fly fishers and those who want to see firsthand what inspired people like Thoreau (Walden Pond at Massachusetts)...For fishing and outdoor recreation, the Oswego County that you describe sounds terrific! Thanks for sharing! Trust others will add to your travelogue and detailed account of the regional activities... Moses

Papa, I have lived and breathed Jeep 4WD vehicles for fifty years now and have authored three bestselling Jeep books (Bentley Publishers) that each earned a Mopar official part number. I still discover new Jeep information and facts! I, too, taught, serving as an adult education level automotive/diesel and welding instructor at the Rite of Passage program before advancing to Director of Vocational Training and Site Supervisor of Education...My work with tough young men (often gang affiliated when they entered the program), many eager to learn and dedicate themselves to a productive life through technical training, proved challenging, humbling and, ultimately, highly rewarding. These students raised the bar for my effectiveness and sense of purpose, and I credit them with making me a better teacher... Thanks very much for your comments, I value your feedback and am very pleased that the information serves well! Looking forward to your thoughtful topic posts. Moses

Yep, a rock and a hard place! You're right, there is no "silver bullet"...Sounds like cellular would be similar to the Wi-Fi at Starbucks: great when available. Wi-Fi cafes are largely an urban phenomenon. At Moab and other places, the RV trailer parks now have Wi-Fi. However, there's no promise of evening bandwidth availability when everyone in town is drawing down the local server with streaming Netflix, Facebook, YouTube and Twitter—as the night drags on, speed and bandwidth dwindle to something like the 24K modem and analog phone lines at Yerington. Nothing's perfect, and you do paint a brighter future. For now, Wi-Fi and spotty cellular access can at least keep track of the magazine's 450-plus URL pages and its dozens of dedicated-domain, Vimeo Pro hosted HD video frames. I'll add more info as this "connected at the woods" venture unfolds...Thanks for the reality check, Megatron! Moses

biggman100, this is very helpful! Even for the smaller shop facilities that I've operated, there never seems to be an adequate first-aid kit available. Either a company designs kits for commercial EMTs or has nothing more than the bare essentials for small-scale use. If others would like to comment on Eastern Mountain Sports and other sources for first aid kits, and ways to make sure we have adequate safety equipment for our families and friends afield, please jump into this discussion! Moses

At the 4WD Mechanix Magazine 'Tech and Travel' Forums, the goal is meaningful discussion groups and forum communities. We value everyone's input, and when member "biggman100" made the following suggestion, I promptly responded: "I have a suggestion for the forums. We should have an off topic area that isn't specific to any one make or model, so users can post comments or suggestions relating to the off-road community, items that wouldn't otherwise fit in any one category. Like, for an example, say a new style multi-fit bed tool box comes out, and someone wants info on it. Or maybe someone would like to share experiences with a certain off road parts supplier—that kind of thing...I have a question that has been submitted to every forum I am on. It's about time to get my wife a new car, and I'm curious about AWD sedans. I have been asking around for opinions but haven't yet found a place to post such a question..." Well, biggman100, please post your full question at this forum! The new "Let's Talk!" category and these four new forum groups are specially set up to field these kinds of questions. Thanks for your suggestion, it's now a part of the message board communities! Moses

Megatron, very insightful! I'm still laughing about making a sandwich and watching the sunset as the data uploads to the internet! I took a quick look at satellite services, the affordable ones tie to HughesNet. A bit of history: We lived and I wrote from Yerington, Nevada for years. We began our internet access with a 24K modem to a local server host, with bandwidth, as we used to say, generated by squirrels running in a cage. This thin stream of data fed through our archaic, analog telephone lines, which would unexpectedly disconnect at odd times in the winter months. Next up was the quantum leap to a Wild Blue dish (somewhat like HughesNet). I could actually upload a light URL page in just minutes—as long as Nevada Energy wasn't dropping electrical service on our rural power line to satisfy big agriculture's irrigation and pumping needs during the summer season—and barring January or February storms that would smother the receiving dish with blizzard snow every ten minutes. The magazine's location at Fernley revolutionized our internet access. Charter, frankly, has served us well. Plenty of speed up/down (4-5MB up, 10-15 down) without a high monthly cost. Given our historic experience, this is really something and certainly acceptable for the magazine site's maintenance and HD video uploads to Vimeo Pro. Fast enough. Given your expertise in cellular, is there a cellular solution that makes sense? Satellite with any speed is too costly, but cellular with current 4G available in many locations must have some potential, right? We're using Verizon, would otherwise consider Sprint, and I appreciate your comments here. For years, we had AT&T for cellular phone service and discovered its perfect score for dead cell areas that never improved, despite the AT&T claim that the company was "constantly adding towers"—certainly nowhere near rural Nevada! On trips to Moab, Utah from Fernley, we have traveled from just east of Fallon, Nevada to Delta, Utah, along U.S. Highway 50 ("The Loneliest Highway in America"), without any cell phone reception—either from AT&T or any partners in the area: a distance of 437 miles! This and chronic dead spaces from Yerington to Silver Springs, Nevada, and from the Humboldt Sink NE of Fernley all the way to Wendover along I-80, made us believe that AT&T meant, "You'll only have service when you don't care, and never where you might really need it!" Despite promises to build more towers, AT&T apparently held out for the next leap in technology. The combination of fiber optic and RF sounds promising, though likely expensive for consumers initially. (I did spot the RF fixture atop the stealth pine tree, it's at the upper branch, right side, right?) A visit to the local Verizon office a year ago to consider an Android and similar options left my wife and me scratching our heads. Would 4G and a tablet make sense, and is that cost effective? Is this an alternative to a satellite dish on the trailer? Could I keep the magazine fresh and running (including uploads to the server and Vimeo) from the Rubicon Trail or Black Rock Desert? Your comments about traveling deep into the woods or desert and watching the signal get steadily dimmer is all too true! We do magazine coverage at places like Moab, Utah and High Rock Canyon, Nevada—as a general rule, the words "canyon" and "cellular" should never be used in the same sentence! Your thoughts? Comments from others? Moses

Sounds like you're on the right track, Joe Mac! I would contact EBC and ask if there is a pad set compatible with your OEM rotors... Moses

Hi, Papaobewon, thanks for posting your first topic! You have given us all an excellent opportunity to discuss the concerns around buying a used Jeep TJ Wrangler and aftermarket equipment. There are many vehicles out there, as the TJ was extremely popular in its 1997-2006 production period. I'll describe some things to look at and question regarding this particular Jeep for sale. My intention is not to berate the vehicle or the individual offering this 1998 TJ Wrangler 2.5L Jeep for sale... Here are two distinctly different Jeep TJ Wrangler profiles. At left, a hardcore trail runner does what you would expect—drives the hard trails and works the suspension thoroughly! At right, a very clean Jeep TJ Wrangler with hardtop boasts factory and mild aftermarket upgrades—for a very long life expectancy. First, let me distinguish that a 2.5L YJ or TJ Wrangler has a different frame than the 4.0L six-cylinder frame. This is important if you decide that four-cylinder power is "not enough" for the weight or usage you have planned. With all of the accessories and add-ons that this Jeep features, the 4-cylinder engine is toting quite a package, so fuel efficiency will be only marginally better than a 4.0L six-cylinder model. The 2.5L pushrod OHV engine is a great design, AMC's contribution that Chrysler carried forward until the introduction of the 2.4L high-tech engine. It does a good job when not taxed too much, and the axle gearing is 4.10/4.11:1 on these models with the larger case Dana 35 differential. The transmission is an AX5, the lighter version of the AX designs yet with the right gearing for a four-cylinder engine. Six-cylinder models use the AX15, which does offer a higher torque rating. To use the AX5 with a six-cylinder engine, you would need an adapter. If you wanted to make that swap, the YJ or TJ Wrangler changeover involves relocating and building motor mounts because of the frame differences. (Click on the link to see my MIG welding project.) This includes differences in the location of the rear transmission mount as well, a lesser fix that involves the skid-plate/crossmember. For these reasons, it's very important to decide whether you want a four-cylinder versus a six-cylinder model at the onset. In making that choice, there are a variety of motives. Some purposely buy a four-cylinder if they plan a V-8 and alternative transmission swap into the Jeep. Others believe the four-cylinder will get the job done and deliver better fuel efficiency, which it does to a degree—until the weight of the modified vehicle taxes the engine to the point of offsetting the fuel efficiency. I'd like to draw attention to the performance curves of the 2.5L inline four versus the 4.0L inline six: The four develops its peak torque at a higher rpm, horsepower peaks at 5,400 rpm, a virtually unattainable speed under most driving conditions and surely not fuel efficient at that speed. Compare the two engines and transmissions at: http://www.allpar.com/model/cj/specs.html. This is a 1997 Jeep TJ Wrangler spec readout, the same as the 1998 you're considering. Also noted is that some base models did not have power steering, I'm presuming this Jeep does? You need it. As a footnote, even the 4.0L inline six has a stodgy torque rise in my view, peaking at 2,800 rpm. By contrast, the legendary 4.2L inline six that contributes its crankshaft to the 4.6L stroker motor build-ups reaches peak torque between 1,600 and 2,000 rpm, depending upon the year model. That's diesel-type torque and why the 4.6L stroker motor is so popular! As for the off-road performance of the four-cylinder models, they do quite well. Gearing in low range makes the engine sufficient for the job, and the MPI (1991-up) version of the 2.5L fuel injection is quite stable in slow crawling. I'll address each feature in the order you listed them in your post: 1) A rebuilt or remanufactured engine should have receipts. A remanufactured engine is sold as a long block or short block (without rebuilt cylinder head); the complete long block includes the cylinder head and is desired here. A rebuilt engine should have receipts for machine work as well as parts. We can discuss the details if receipts are available. 2) Since this is a four-cylinder model, it has the AX5 transmission as I described. 3) The description sounds good: a fresh engine, 138,000 miles, only 3,000 on the new engine. Black is an awkward color, draws heat and tends to oxidize faster. The peeling or "crazing" is not uncommon for a black vehicle exposed to a lot of sun or parked outside. 4) A 4-inch lift is common, the body lift is mild as is the motor lift; if done right, this is an asset for off-road use. 5) Swing-out tire carrier is a plus. 6) Aftermarket sound is nice if a quality system and installed properly; always concern about wiring during the installation, must be done right. 7) Tires and spare sound good, 31" is not radical, and the OEM 4.10/4.11 gears can tolerate this diameter tire well. Speedometer may have slight error if not corrected for the 31" tires, this can be remedied with a speedometer drive gear/tooth count change. Note: It surprises me that there is this much suspension lift plus a body lift for only 31" diameter tires. A four-inch suspension lift will accommodate 33" tires, which would require a ring-and-pinion gear change to 4.56:1 or even 4.88:1 for restoring performance. Maybe this vehicle did have 33" tires at one point; otherwise, the combination chassis and body lift is actually excessive for 31" tires. (A two-inch suspension lift would be sufficient for 31" tires on a TJ Wrangler.) The 31x10.5 tires are likely on 8" rims, and that's really not much track width increase for the amount of lift. For this amount of lift, I would do a 10" rim with 33" tires to widen the track width and help restore the vehicle's center-of-gravity. 8) Adjustable track bar is desirable with a link-and-coil suspension lift. This allows precise alignment to eliminate axle offset or dog tracking. Suspension parts and axles need to match up and align when there is an aftermarket lift on link and coil suspension. 9) New shocks and stabilizer are a plus if "new" means quality replacement parts. Gas-charged shocks are preferred here, Bilstein or equivalent. 10) Long sway bar links needed to compensate for the 4-inch suspension lift. 11) Stronger control arms, if quality made, are a major improvement over the stamped steel OEM arms. 12) Cold air intake can improve performance. System should not permit exposure to water, however. Any open faced air filter should be kept away from the spray or slosh of water during stream crossings! Sucking water can cause engine hydro-locking and severe internal engine parts damage. 13) Quality fog lights can be useful for the trail; make sure they're quality with safe, proper wiring. 14) Same as windshield lights; great if done properly. 15) Diff guards are a real plus for off-roading in rocky terrain. 16) Full skid plates are a plus, too! This adds weight, though, and we're talking four-cylinder power in this case. 17) The security console is a real plus, especially when parking the vehicle with the top removed. 18) Okay on the tint if legal and visible. Not sure of the motive. 19) Receipts useful here. Quality parts should be verified. Is the clutch new, too? Flywheel new or re-surfaced? Should be included with an engine replacement or rebuild. 20) Hardtop, especially factory type, is a valuable accessory! These tops are expensive to purchase later, a hardtop has many advantages: weather protection, security, added value. Downside is weight, another tax on that 120 horsepower engine. 21) Undercoated frame can be okay. Is the vehicle at a climate without salted roads? If salted, inspect the chassis and body end to end for rust and any signs of body or frame rust exfoliation. Undercoating is great if applied for the right reasons—not to cover rust, though! 22) Clean title is a must... 23) Chipping paint is back to the black. If the price is right and you want to restore this vehicle cosmetically, you can do so. Regarding your last questions, a MOAB sticker can be good or bad. I've been to Moab since the mid-'nineties and witnessed vehicles used moderately by responsible folks, and I have also seen vehicles pounded mercilessly and abused, even wrecked—often due to driver inexperience. That said, Moab does mean something—what it means depends upon the driving skill of the owner and which trails the Jeep took at Moab. The same applies to the Rubicon Trail, Fordyce, Sierra Trek and so forth. Get underneath and inspect the Jeep end-to-end. The most critical and expensive areas are the frame and axles. Look for signs of collision repairs and trail damage, abuse and so forth. Aftermarket products like lift kits have "perishable" components such as urethane bushings, Heim joints and other pivot points. Drivelines are a source of trouble, and this Jeep TJ Wrangler should have a slip yoke eliminator (SYE) kit at the transfer case outlet to the rear driveline plus a CV-type rear driveshaft. If not, the rear driveshaft is at risk; U-joint life will be short, driveline vibration likely. Look for signs of rock-sliding along the control arms and other symptoms of hard use. Look for scarred diff skid plates. See if the steering gear is loose by manually moving the pitman arm back and forth with the vehicle parked, its front wheels pointed straight ahead; drive the Jeep and feel for steering wander and suspension looseness. Signs of trail use are not, in themselves, a reason to pass up the vehicle; however, scarring and looseness do suggest the kind of use the vehicle has seen. In addition to writing for the 4WD magazines, I wrote for Popular Hot Rodding and several other muscle car and high performance magazines in the 'eighties and 'nineties. My tech Q&A columns would often receive questions about purchasing a used muscle car or Corvette with "low mileage". If a muscle car had "only" 50,000 original miles, I would reply that this could potentially be 200 trips down a quarter-mile drag strip! For a 4WD trail vehicle, 138K miles could be many thousands of trail miles. Metaphor: The notorious Rubicon Trail is only 12 miles long. We can "do the math". Although none of these comments are meant to discourage your purchase, a used trail vehicle is all about its history. Modified vehicles are typically intended for hard trail use, so you do need to adjust your purchase price to allow for any parts damage from trail pounding. I would test drive the vehicle with an ear toward axle/differential noises, transmission synchronizer noise and feel (including "jumping out of gear"), clutch and driveline response, plus the drivetrain play and sounds in 4WD low range. Look closely at the front axle shaft joints in the steering knuckles. Steering knuckle ball-joints and steering linkage joints can be worn out by this mileage from a lot of trail crawling or oversized tires. Inspect the front brake calipers and rotors, they're visible. Look at the drivelines and check for worn U-joints, grease seepage and a torn boot. A major oil leak at the rear main seal can be a nuisance and ruin a clutch disk. Axle pinion shaft seals and the transfer case output seals are other areas to check. Anticipate what you want to do with the Jeep and how the modifications impact your use—or dovetail with it. Also weigh the cost of outfitting a stone stock 1998 TJ Wrangler with these upgrades. Consider a stock vehicle with an extraordinary history, something like "driven on icy highways but never off-road," "driven only on graded gravel—occasionally," "used to get back and forth to work in the winter," "used to access a ski resort in the winter," "not sure what this lever position [4WD/low range] does, I've never used it" —fill in the blanks. My brother-in-law found a 1999 Jeep TJ Wrangler, stone stock with 70K original miles, the auxiliary cloth top never installed, the hardtop never removed, the wheels and tires stock with one OEM tire replacement; the engine is a 4.0L with 3-speed 32RH automatic transmission—owned by a mature couple, they never went beyond a graded gravel road with the Jeep and used it primarily for basic highway transportation and winter driving. He paid $6500 for the Jeep. It is prime for any kind of personalization and modifications, virtually a "new" Jeep TJ Wrangler. While this sounds extraordinary, it's not a Rubicon model. For "hardcore" wheeling, the Sport model could use a rear locker. (Note: Some non-Rubicon TJs actually have the Dana 44 rear axle with limited slip option.) There would be a need for a lift kit, 4" for 33" diameter tires. Then all of the other driveline, SYE and other modifications...The cost of parts—and labor if you sublet all of this work—must be considered. It's not easy making these choices. The best way to approach this is as an "informed" buyer. I trust that these comments, the magazine and the forums help. I and many others can contribute additional comments and ideas, so please ask. It's for the benefit of everyone! Moses

As the publisher of 4WD Mechanix Magazine, I often find myself covering events and subjects at remote areas or outside the Starbucks or motel/hotel's Wi-Fi internet access. The magazine and forums require ongoing access. Sometimes HD video news warrants immediate uploading to the 4WD Mechanix HD Video Network at the magazine website... Does anyone have experience with reliable, or for that matter unreliable, mobile or RV internet access equipment and services? The aim is to be anywhere within reason and still remain connected. I understand the satellite needs: a clear line of sight South and no dense cloud cover. We used Wild Blue (Hughes) coverage years ago. Upload and download speed is very important, cost is always a consideration, and reliable internet service is a must. Any insights here? Appreciate all comments, many of us need more than "Dish TV" and HBO in the wilderness. A trip to Alaska along the Alaska Highway through the Yukon cannot mean the end of internet access—or magazine connectedness. Moses

Joe Mac, EBC has a reputation at racing and high performance braking. I reviewed the corporate website, and it looks like a good all-around approach would be the Extra Duty Orange Pads with GD Series rotors. Given the road speeds you describe and your significant off-road use of the Jeep, I would try upgrade pad material before changing out the rotors. A rotor upgrade bumps cost up considerably. I would research EBC's pad recommendation for stock rotors. If necessary, resurface the rotors, which is simpler and more accurate with contemporary on-the-vehicle resurfacing equipment. This addresses any discrepancy in the wheel hub alignment and provides a rotor that runs true with the wheel hubs—all machining is with the rotors in place. This way, you could see the difference in the pad composition. You're neither in a racing environment nor situations where brake heat and fade should be issues. "Fade" at a low 35K miles is likely due to moisture/water in the brake fluid. Your factory DOT 3 brake fluid is hygroscopic, drawing up to 3% moisture per annum. Actual moisture contamination is usually less with a bellows type master cylinder seal and cap—or other modern master cylinder sealing methods. Your Jeep has low mileage, which means it's parked a lot, and this makes it more vulnerable to the hygroscopic effect of the brake fluid. If you live at a humid climate, this adds to the problem. You have "bled" the brakes. If this was a vacuum bleed from each of the calipers, I would be confident that all old fluid and debris are gone. Pedal pumping bleed jobs and even pressure bleeding from the master cylinder end do not guarantee full fluid evacuation if the calipers remain assembled. These are some thoughts. Perhaps others can jump into this discussion with actual experience around aftermarket upgrades to the OEM brakes on a Jeep Wrangler TJ Rubicon... Moses

Very helpful, biggman100, you've drawn some lines on what can be expected from the different levels of basic readers and scan tools, and as you aptly describe, an increase in price does not necessarily guarantee more functions. It's important to note that scan tools have far more functions than a very simple code reader. I bought a Harbor Freight basic code reader to carry in my off-road tool box. This very inexpensive device came with a code book (hexadecimal) for OBD-II. I would describe the Harbor Freight tool as simply an alternative to those vehicles that enable you to read a MIL stored DTC by cycling the ignition switch: Three times on-and-off in succession, and our '05 Dodge Ram/Cummins 3500 will deliver an instrument panel LED readout of the stored DTC(s). The Harbor Freight reader will even erase the stored DTCs; maybe not a big item, as disconnecting the battery will do the same; however, disconnecting the battery also means having to reset the clock and other battery powered time functions. So, like biggman100 clearly shares, if you want actual data and useful stored or streaming information, including the PC download option, make sure you're getting those features. Thanks, biggman100, for leading the discussion forward! More experience and insight to share out there? Join us! Moses

Wow, RareCJ8 and biggman100, now this is community! We're getting detailed, viable technical information to our fellow members and guests. The photos are highly useful, too! Very thoughtful, accurate and thorough discussion...Thanks much for your input, guys, JJ should have plenty of facts and ideas for his Jeep battery cable restoration or upgrading! Moses

Like JJ, I'd like to hear what's new in quality aftermarket battery cables...'In the day', I wrote endlessly about cable upgrades, in particular Wrangler Power Products custom cables for winches, auxiliary batteries, and onboard welders. I emphasized in my Jeep and other truck books that grounds are as critical as hot leads. Every 4x4 magazine project vehicle I've built with a high output charging circuit or onboard welder had an upgraded battery cable system. You need quality grounding from the battery to the engine, engine to frame, frame and engine to the body and so forth. Amperage gauge for each positive and negative cable on my custom systems was always 1/0 welding grade cable with proper industrial grade, high amperage rated terminal ends. This is a science: Body, engine and frame cable attachment points cannot have resistance or voltage loss/drop due to paint, rust or a corrosion barrier. JJ, your comment on the Jeep Wrangler's ground to the engine and body is very important. A substantial body ground protects the PCM and other electronic devices. Newer vehicles with CAN bus have even more complex ground needs. Welders onboard are a whole other story. You need to set up grounds to make current take a short path to the welding ground point—without passing through the PCM, wheel bearings or any other critical point. PCMs have been destroyed by improper ground circuits and onboard welding. Visualize: You're fixing the vehicle at remote country, the welds look great, and the PCM is smoking! So, if anyone can recommend a source for cables, even OEM replacement cables of quality for JJ, let's add to this discussion! JJ, if you need OEM part numbers for the original battery and ground cables, I can furnish Mopar part numbers... Moses

JJ, I just received the latest Actron offering for testing: the U-Scan 9599. (Follow the link for all the details!) OTC/Actron/SPX/Miller are now all under the Bosch umbrella, which is a real plus for consumers. U-Scan is a Smart Phone view device and has a number of available upgrade apps that include real time sensor readouts. You do need the app upgrades to take full advantage of this technology. You need a Smart Phone, too! Technology is advancing rapidly. U-Scan's upgrade "apps" are trendy and fit the Smart Phone culture. Be aware that code readers and even their advanced apps are still talking only one way: from the PCM to the reader, whether receiving simple OBD-II or CAN BUS numeric codes or "watching" the sensor functions in real time graphic simulations or various graphs. These simulations are essentially continuous reads of streaming data. The next diagnostic scan tool tier is well over $1000, 10X the cost of the basic U-Scan reader. From $1000 up would be programs that allow uploading information for permitted re-flashing of the vehicle's onboard computer. Tools like the Chrysler DRBIII dealership level Chrysler/Jeep scan tool can actually reprogram elements of the onboard PCM or ECU/ECM software. I borrowed a DRBIII scan tool from friends at OTC/SPX Miller tools to produce the HD video on speedometer recalibration. Click on the link and take the time to watch this video. You'll see the difference between uploading and downloading data. Speedometer calibration was just the tip of the iceberg for functions you can perform with higher end, interactive scanners and diagnostic tools. OTC offers Genisys, Snap-On has its programs, tools in the $5K or higher price range, aimed at shops doing pinpoint diagnostics and troubleshooting beyond code reader-based technology. DRBIII and other high end dealership level programs can actually operate and test the engine's sensors and other fuel-and-spark management devices in real time, paired with the PCM/ECU functions. They also offer ABS, air bag and other systems troubleshooting. As you discovered with your OBD-II scan reading for the "#1 Cylinder Misfire", scan tools can sometimes be limiting. However, that is no reason to pass up the new generation, advanced code readers and data streaming devices! You can often pay for a tool like the U-Scan, or even a $29 code reader from Harbor Freight, with the very first DTC (diagnostic trouble code) readout. For many troubleshooting projects, the stored MIL codes serve well. I'd like others to comment on their scan tool experiences. This is an area of real interest, and the best judges are actual users with insights to share! Moses

This is very helpful information, Nevada ATV, and welcome to the posts! I have a friend in engineering at Chrysler/Jeep powertrain, and Ray is an avid ATV guy. He's talked about Dalton Clutch, and they do extreme ATV riding with engine performance mods and suspension work. Oversized tires I'm sure get into that mix. I'll see if Ray has time to enter this discussion, he can "do the math", too! Moses

JJ, sounds like that new Mopar TPS made a huge difference...Good news! The battery cable is very important, actually both negative and positive cables must be in good shape, as this is a D.C. system where both "hot" and "ground" circuits need the same amperage carrying capacity. You need a consistent 12.4V or higher (12.6V or higher is a fully charged battery) for the PCM to be happy. A bad cell in the battery or an open at a battery cable can stop the engine from running—even if the alternator still functions properly. We experienced this with an intermittent 10.5-volt reading on the XJ Cherokee's battery. The engine would barely keep running. A replacement battery immediately eliminated the issue. Looking forward to your posts, JJ! Moses

You've done your homework to this point, Joe Mac! Keep us posted on your choices... Moses

Well, you're certainly opening my eyes to the value of humor in these posts! Keep it up, Megatron... The Gear Vendors is definitely an option to consider before you change axle gears. Here's some quick math on the Gear Vendors 0.78 ratio overdrive with your 48RE automatic transmission and a change to 5.13:1 axle gearing: At your favorite highway cruise speed of 75 mph, if you use the Gear Vendors overdrive plus your 48RE's overdrive, with 37" tires (560 revs per mile) and 5.13 axle gearing, your engine speed would be 1932 rpm. From my experience with our 3500, this could be close to the optimal cruise rpm for maximum fuel efficiency at this weight, height and speed. If you needed passing or pulling power, without the need to floor your 48RE for a forced downshift to third gear, you'd simply kick out the Gear Vendors overdrive and be at 2478 rpm. This is the best of both worlds and does target your 75 mph cruise speed. If you slow down to even 70 mph, you'd be at 2313 rpm with the 48RE's overdrive and direct gear on the Gear Vendors. Apply the 0.78 Gear Vendors overdrive, and engine rpm would drop to 1803 rpm. You get the picture, this looks like some targeted rpm options for optimal fuel efficiency and still above the torque peak rpm in all cases. By the way, it's very nice of me to help spend your income on items like a Gear Vendors overdrive! Kidding aside, this could pay big in fuel savings and also offer some incredible torque and pulling options as a split-shifter. Neither you nor I currently have the advantage of the latest 8-speed automatics—unless you toss the Gear Vendors overdrive into the equation! This is the wave. Again, here is a copy of the Gear Vendors link I provided in my last missive: Gear Vendors overdrive when practical. Gear Vendors is in the gear business, and they build an impressive case for torque gains through nothing more than gear ratio changes and split shifting. The OEMs have obviously gotten the message with the new wave of 6- to 8-speed automatic transmissions—which will make manual transmissions in light- and medium-duty trucks a thing of the past. Before taking the plunge, consider your GVCW (gross vehicle combination weight) with the trailer in tow and the stamina you can expect from a Gear Vendors overdrive. As for winter oil changing and specs, consider the wide range of climates and engine operating temperatures that OEMs address. Oil recommendations must be generalized and take into account the temperature range from startup to warmed operating temperature under load. Dicey choices! 0- or 5-wt. motor oil is great for cold pour in Alaska—but not for the very same engine running at 195-degrees F thermostat temperature once it warms up. Minus 50 F to 195 F is a wide temperature range—from cold start to fully warmed up—a typical Fairbanks, Alaska day in the dead of winter! Regarding the 80 mph method of getting the engine to rpm, save the speeding ticket. (Try running to 80 mph on some secluded road and let me know whether the engine likes it...Watch your rear view mirrors for flashing red and blue lights.) Note that when you increase load like with a trailer in tow, you may need horsepower in addition to torque. The Cummins 5.9L ISB engine is under no stress at stock 7,800 pound curb weight and OEM height; loping along at 1,600-1,900 rpm seemed just fine under that scenario, with road speed peaking around 69 mph. To push our "billboards" down the road at 80 mph creates high rolling and wind resistance. You did the math perfectly for your 37" tires, 3.73 stock gears and 80 mph in 0.69 overdrive: 1,922 rpm. The question is whether the engine would be happy at that rpm under heavier loads. I used to periodically run our truck to 100 mph in a sprint up a particularly secluded highway in the desert. The grade was over 6%, and I would start at the bottom around 65 mph and accelerate to 100 before the crest of the relatively short grade. With the truck's current weight, the lift, tire drag and even the right axle gearing, the engine would perform this feat under load now—even with nothing in the bed but the auxiliary fuel tank. Times change—we still like the look and utility, though, right? Now we're talking about the constraints that drive Cummins to declare that our engines should never run below 1,900 rpm under load, and they want to see us running 2,100-2,400 rpm with "commercial" loads. Driving your lifted truck 80 mph is a pretty good load, perhaps comparable to "commercial use" standards. Here's engine performance data on the Cummins ISB 24-valve 5.9L inline six: http://www.cumminsdieselspecs.com/24v.html. Our engines peak their horsepower around 2,900 rpm. Most ISB commercial applications have 3,200 rpm governors. Chrysler and Cummins added a couple hundred rpm for those Ram owners who think they're driving a gasoline powered vehicle, even though the engine's power has fallen off considerably and shifting to the "next gear up" would be a better idea. The horsepower rpm is worth considering. While peak fuel efficiency at a light load is 1,600 rpm, without getting into physics, we can assume that if we continue adding a load to the engine, we will need more horsepower. An H.O. engine peaks at 325 horsepower, quite impressive and requiring 17.2:1 compression. So, you're right in suspecting that as the load rises, fuel efficiency suffers. Of course it takes more power to move over four and a half tons of mass at 80 mph. Then there is the aerodynamic (lack of?) drag coefficient we know is lurking. In terms of drag coefficient, all I could drum up on line was for a stone stock model year 2000 Ram 3500 4WD Quad Cab: 0.48 rating. If you'd like to see how this stacks up against other vehicles, ranging from sleek race car models to popular econo-boxes designed for peak fuel efficiency, or even some SUVS (much like our trucks), check out this well-done Wiki entry: http://en.wikipedia.org/wiki/Automobile_drag_coefficient. The cool thing about the diesel engines in our Ram trucks is that the torque stays well up there from 1,600 rpm to at least 2,700 rpm! This means that unlike a gasoline engine, the torque and horsepower don't go separate ways with advancing engine speed. Diesel technology does require a re-think on the part of gasoline "performance" enthusiasts who see horsepower figures as an end all: Unlike diesel torque rise, high horsepower figures are only attainable at higher rpm. This even applies to the popular Jeep 4.2L/4.0L hybrid "stroker motor". Begin with a reliable inline six. Build a "hot" stroker for 300-plus horsepower, and discover that to achieve this kind of power, you'll be pushing the torque and horsepower peak rpm way up the scale. Here are figures for an exotic Jeep 5.0L stroker gasoline engine built from a 4.0L inline six block with a custom stroker crankshaft and 11.5:1 compression: 344 horsepower @ 5300 rpm and 384 lb/ft torque @ 4000 rpm. Great performer for sand drags—lousy power curve for the Rubicon Trail! The analogy for a Cummins diesel is that maximum high performance/horsepower builds (those short lifespan engines that Gale Banks talks about) mean spinning the engine to oblivion to achieve peak power. Gone is the famous torque rise that distinguishes a long stroke commercial diesel engine—or a stock 4.2L Jeep inline six for that matter—from the typical gasoline engine... Regarding the principles of water/methanol injection and its history, here's a nice ditty: http://en.wikipedia.org/wiki/Water_injection_(engines). A water/methanol injection kit like the one offered by AEM reminds me of one of my earliest freelance magazine pieces. We had a '73 Chevy K10 4x4 SWB pickup with a 350 V-8. I installed a "solution" injection kit that was popular in the '70s. That somewhat sophisticated system came with a thick carburetor base gasket that had small orifice tubes running into the throttle bores. A needle bleed valve at the glass solution jar metered the water/alcohol mix. A slight bubbling indicated proper adjustment and flow. Pretty slick, actually, the device did what water and alcohol/methanol injection will: On a gasoline engine, it cooled and condensed the incoming fuel/air charge, reduced ping or detonation, allowed for more spark advance and better power, and permitted use of higher compression ratios. Such a device allows fuel timing and compression changes on a diesel as well. Not often mentioned, during the combustion process, the water/alcohol or methanol solution will remove carbon from the combustion chambers, valves and piston crowns. Upon the 350 V-8 teardown, the cylinder heads and upper engine looked virtually "new". In this modern era of electronic fuel and spark management, carbon buildup is a virtual non-issue. In the era of the Quadrajet carburetor, however, fuel enrichment and "venturi effect" made carbon deposits at the upper cylinder and combustion chamber areas a chronic engine problem. Fuel efficiency improved dramatically, the 350 V-8, gasoline powered truck delivered as much as 18 mpg with 3.08 gears, a 1:1 fourth gear ratio in the SM465 four-speed and 33" diameter tires. Performance improved noticeably from added spark advance—without signs of ping/detonation. For your diesel, this injection would act like an additional intercooler, keeping exhaust gas temps lower for less stress when trailering or hauling a load. The upper engine would be cleaner, possibly extending engine life. As with GDiesel fuel, crankcase contamination from incomplete combustion would be decreased. Combustion would be more thorough. Is this enough to outweigh the cost of methanol/water injection? Can't say for sure, but this is why I buy GDiesel locally for 10-12 cents a gallon more than other low-sulfur diesel pump fuels. I'm "banking" on the engine yielding a cleaner tailpipe, cleaner crankcase (lab tested the oil at Pape Cat, it's holding up much longer and shows fewer contaminants at change intervals) plus extending engine life. If water/methanol were used for this purpose, I might buy it... Moses

Hi, Joe Mac...We all look forward to your thoughtful and insightful questions! You've done your homework on this trailer purchase! The camper is one more reason for a lightweight trailer, and your extension hitch makes the trailer's handling important. When you load the trailer make sure the torsion bars accommodate the trailer and offset the camper weight. A unique advantage of the equalizing hitch is that it spreads your 6500# or so trailer load over the entire set of axles: the truck's front axle (IFS in your case with a Chevrolet), the massive beam rear axle with hefty springs, plus two trailer axles. View the equalizer hitch as a set of torsion bars that link the two vehicle frames (trailer and truck) together. An alternate, maybe more descriptive name is a "load distribution hitch". The hitch and torsion bars spread weight over all of the axles and spring sets. This levels the entire load through the force applied at the torsion bars. Envision all the tongue weight that would otherwise be on the hitch ball without these bars. The desired tongue weight is typically 500-600 pounds for a Class III platform hitch; 1000 pounds with a WD or equalizing/weight distributing hitch. (See this detailed Reese description of hitch ratings: http://www.reese-hitches.com/learning_center/general-towing-classes.) Your Silverado 3500 truck likely has a Class IV or V rated hitch, which raises these ratings, as described at the Reese link. However, you also carry a hefty camper, which loads the tow vehicle substantially and reduces its overall weight capacity. This is where Gross Vehicle Weight Rating is critical, per axle, when determining the actual load on your truck. Without these bars spreading the load between the two frames and all axles, the trailer tongue weight would grossly exceed the safety rating for the truck's OEM platform hitch! Add a camper, and your rear springs would be taxed to the limit. Think of torsion bars as tensioning beams. When you adjust the bars for just the right set and hitch ball height with the loaded trailer, the weight that would otherwise be on the hitch ball gets distributed over the two frames. This actually transfers or "distributes" the load to each of the axles. In the process, as the torsion bars apply tension to offset a particular load, you will discover an amazing side effect: The truck and trailer rise and set together! This stabilizes the handling and helps eliminate the bucking and hitch dive that occur without an equalizing/load distribution hitch! Rick Preston, owner of Rick's RV at El Cajon, California taught me about the value of an equalizing hitch in the late 'eighties. I had a Land Cruiser FJ40 project for OFF-ROAD Magazine and a long term (one year) test of a StarCraft 21' travel trailer. The FJ40 had a 90-inch wheelbase, very short coupled for trailer pulling. To offset this liability, we installed a platform hitch (featured in my Toyota Truck & Land Cruiser Owner's Bible, Bentley Publishers) to accept a load distribution Draw-Tite hitch assembly. The Land Cruiser was well equipped on the performance side, a 383 Chevrolet stroker V-8 transplant with a Ranger Torque Splitter transmission between the Toyota gear box and engine. I had also installed Saginaw power steering...On 33" tires and 10" rims, the track width was safe for towing! So, off we went to join the Toyota Land Cruiser folks at Diaz Lake near Lone Pine, California in the late fall. Thanks to the load distributing hitch and a sway control brake, we got there in one piece. The side and head winds blew 45-55 mph across the Mojave Desert, yet the 'Cruiser and travel trailer tracked straight as an arrow. We even marveled about the 4x4 and trailer smoothing out the rolling dips and rises on old U.S. Highway 395 between Adelanto and Inyokern. So, the WDH is a necessity, not an option, Joe Mac. Enjoy the highways and trails, we'll enjoy the updates on your plans! Moses

JJ, this is good news...Trust tomorrow's drive will prove equally productive. The TPS should be considered a "perishable" wear item. Think of the duty cycle and how many times that stem has wound up and down the tension and voltage curve in 250K miles. In my own experience, the TPS and the wire from the crankshaft position sensor to the engine harness can deteriorate over time and create "gremlin" issues like you experienced. Another issue on engines with rear main seal seepage is engine oil on the toothed ring for the crank position sensor or on the sensor pickup itself. Each can cause erratic error messages that often dance around the actual problem. We're awaiting your update and optimistic. It certainly was productive to change this TPS, and your Mopar parts choice assures accurate calibration of the new TPS. Please share the follow-up! Moses

Hi, Joe Mac, and welcome to the forums! I'll jump into this discussion, and let's encourage others to join... We have a steel trailer with wooden deck boards, and it has served well. From experience and considering your weight over the road, however, I would definitely pick the aluminum trailers for ride quality, lighter weight and lower maintenance through time. I'm sure the Kaufman is a great trailer and would hold a load very well. I like the removable fender for getting into and out of the Jeep on the trailer. However, the weight and load capacity are more than you need for hauling a Jeep TJ Wrangler around. If this is your anticipated load, the added fuel costs pulling a heavy duty steel trailer would not be practical. You could haul a smaller backhoe with the Kaufman! On that note, I would get the 18-foot aluminum trailer, as it will haul a longer JK Wrangler, even the Unlimited at 116-inch wheelbase, if you ever consider the next model. (If Jeep brings out a diesel JK Wrangler Rubicon, that might be appealing, although trailering your TJ means that gasoline cost is not much of an issue.) A trail modified 4-door Wrangler with popular accessories, by the way, could easily tip the scale around 5,500 pounds, so the 18-foot aluminum trailer would just do it! Unless you're being price constrained, get the super deal on an aluminum trailer. I trust it's not a dovetail? My experience and watching others, I would avoid the dovetail and opt for ramps and more tail end ground clearance. Unless you have considered a Hensley hitch, the heavy duty Reese that you share in the link is great. I've used a similar Drawtite hitch forever, and the loaded torsion bars often eliminate the need for a sway control apparatus. The Reese looks like it might do the same. Ask Reese if they recommend a sway control (brake) with this hitch arrangement. My two cents! Moses

Thanks for airing these questions, Megatron! Given your truck's weight and lift, as we have discussed, the rpm at 65 mph is too low—but only because of the truck's modified curb weight and wind resistance. I'm not double-speaking, you're at an optimal rpm at 65 mph for extraordinary fuel efficiency with a stone stock '06 Cummins Ram 4x4. Proof: Before I horsed around with 1200-plus pounds of upgrades and a 4-inch lift, in the summer of 2011 I drove to Portland, Oregon from the Reno, Nevada area for the launch of the Jeep JK Wrangler 2012 model (new Jeep Wrangler 3.6L Pentastar V-6 and other changes—see the magazine's JK Wrangler HD video coverage). I consciously held to 65-69 mph with stock 3.73 gears and tires just under 32" diameter. The truck had its stock curb weight and height (approximately 7,800# unloaded). Result: I nailed 25 mpg fuel economy from Reno to the mid-Willamette Valley, Oregon! Best mileage on a long trip ever, including climbs over the Siskiyou Passes and the numerous secondary highway grades between Reno and the I-5 access from Highway 89. This was not the "Plains" and surely not one-sided in terms of grades. That said, if I attempted the 1,600-1,750 rpm under the truck's current curb weight and fully fueled load, worse yet when pulling a trailer, I would expect sluggish performance and mileage. Our Ram 3500 has stone stock tuning to this day, no exhaust upgrades, chips or modifications whatsoever. I drove this rpm range to achieve this exceptional mileage in stone stock form; however, the truck would suffer with that gearing and current 35" tires. Today, cruising at 1,900-2,000 rpm peak, I can coax 21-23 from the truck with the 9,100-plus pound rolling package, unloaded and fully fueled, driving uniform gradient highways...Managed 23 mpg down the I-5 from Sacramento to the 41 Junction en route to Advance Adapters at Paso Robles in January. Held speed to an agonizing 65 mph to achieve this, got passed like I was standing still by the traffic! Pushed to 68-70 and paid for it immediately: 19-20 mpg with 35" tires, 0.69 overdrive and the 4.56:1 gears. Last year's trip across northern Nevada's I-80, through Elko to Salt Lake City and on to Moab, I did manage 22-23 mpg at 65 mph on I-80. Frankly, the Bonneville Salt Flat and Great Salt Lake Basin is tortuous at this speed, although I did have plenty of big truck company in the slow lane. This is the price for maximum fuel efficiency. Diesel engines are rpm and load sensitive! For that matter, gasoline engines fare as bad or worse under load. We really enjoy the truck and its "look". (Objectively, folks at trade shows and the Moab Jeep Safari rubberneck to see this Ram 3500 Quad Cab, as I'm sure they do your Mega Cab!) To a degree, I'm willing to "pay the price". However, my days of 70-75 mph trailer-toting with the XJ Cherokee on board en route to Moab, expecting 17-18 mpg, are over. I'll still expect 15-16 mpg with a trailer in tow, fully loaded, but only after my change to 4.56:1 gears and "governing" speed to a maximum 65 mph when towing. Wind is a much larger factor with the 4" lift and 35" tires, an obvious fuel mileage variable... As a footnote to the trailer toting mileage, I lugged a toy hauler to Johnson Valley for the 2012 King of the Hammers race week coverage. I still had the OEM 3.73 gearing (like you do) and did respect California's strictly enforced 55 mph speed limit for trucks and trailers, holding speed to a limp along 58-59 mph peak. I thought the mileage would be great. Wrong—mileage fell to 12-13 mpg, the worst ever for this truck's trailer pulling and a 7,500# (loaded) trailer. It's all about the right gearing and keeping that diesel happy under load! This raises a point we haven't touched yet. You're weighing the 4.56 versus 4.88 gearing choice for your 37" tires. How about this idea: Install a Gear Vendors overdrive behind the transfer case! The auxiliary overdrive only works in 2WD High range, but you could run 4.88s or, better yet, 5.13 replacement gears in the AAM 11.5 and 9.25 inch axles with the use of the Gear Vendors overdrive when practical—including split shifting on grades with a trailer load. See the interesting torque gains described at the Gear Vendor's website. I've linked directly to the Dodge Ram section. Gear Vendors is a 0.78 ratio or 22% overdrive, which could only be used minimally in tandem with your 0.69 overdrive gear. Final drive equivalent in overdrive/overdrive would be 5.13 x .69 x .78 = 2.76:1. This compares to 4.88 x .69 = 3.36:1 [48RE overdrive without Gear Vendors OD]; or 5.13 x .69 [48RE overdrive without Gear Vendors OD] = 3.54. Your OEM gearing factors currently as: 3.73 x .69 = 2.57. Of course, we haven't targeted engine rpm and your tire diameter yet...We can play with the gearing equation and see if this makes sense. Cost aside, the Gear Vendors overdrive is a consideration if you're on the fence here. ..I've got a one-piece driveline at 140.5" wheelbase, you're longer based with a two-piece driveline. Plenty of room for a Gear Vendors unit in either case. For my truck with its current 4.56:1 gearing and 35" tires, I'd have gains like 1) the double overdrives when running empty at cruise or 2) when pulling a hefty load, I could use the Gear Vendors overdrive with the 48RE in 3rd gear (22% versus 31% overdrive, a 9% reduction advantage). You haven't changed gears yet, so there are more options to consider. I like your seasonal fuel efficiency question! Like the intercooler, winter cold air creates denser oxygen content, which increases power. If your climate is humid in the summer, you may get an additional intake air cooling effect and, therefore, denser oxygen content in the intake stream. A denser charge means improved combustion and, at least theoretically, better fuel efficiency if you can keep your foot out of the more responsive throttle! Another factor to weigh is the OEM or aftermarket computer "chip" tuning that takes advantage of a denser IAT reading by changing injector pulse width. This could also work another way: When winter intake air is cold and dense, the injectors flow more fuel to create the right air/fuel ratio. The result is more fuel consumption and peak throttle response. I believe the winter fuel efficiency loss is also due to lubricant viscosity and cold pour, especially in the axles. (Transfer case lube and ATF are now largely synthetic and wider-range viscosity, typically with a lower weight ceiling.) It's no small fact that OEMs now use lighter, multi-viscosity lubricants for CAFE ratings. The AAM axles call for 75W-90 weight lube. My choice of running 75W-140 Mopar gear lube for severe duty use may, in fact, create a loss in fuel efficiency—especially in the winter. Don't get carried away with this factor, though, unless we're including engine oil viscosity. See this technical paper for interesting details on fuel efficiency as it relates to motor oil viscosity: http://www.instituteofmaterials.com/paper/FEIPaper.PDF. I'm running Mopar 15W-40 year round with use of a winter block heater to avoid startup damage. Frankly, this could be a source of higher fuel use in winter. The 5.9L Cummins engine can drop from 195-degrees F to the bottom of the temp gauge during a 30-minute groceries stop! Another factor, perhaps significant in our case with oversized tires, is rolling resistance. In winter, the advertised or usual static cold tire pressures can create drag. On frigid highways in chilling air, the tires do not reach the predicted temperatures for pressure calculations. In the summer, there is less rolling resistance as inflation pressures rise due to ambient and road surface temperature increases. Sadly, tire pressure is fixed (unless you have a Humvee and can air and deflate on the fly!). You cannot inflate tires to the summer over-the-road pressures for winter use—the tires would be deformed and wear quickly on their tread centers from "over-inflation". They would also be a terrible hazard with minimal road surface contact! As for engine operating temperatures, and this is a factor, it does take "forever" for the Cummins engine to warm when ambient temp is sub-zero to 40-degrees F. This is not a coolant thermostat issue, although 18-wheeler shutter-stats like you hint would be helpful. The Cummins ISB engine has a huge cooling capacity! Forget letting the engine idle to warm up, it will take forever to reach operating temperature. On that note, I'll emphasis that I do use a block heater all winter. The truck is not a daily driver, but on any day with a planned run, I plug in the block heater the night before. Under a carport with a Battery Tender hooked up whenever the truck parks, let's say it is a 10-degree F morning: The engine coolant's startup temperature will be around 120-130 degrees F with the block heater. Warmer weather (a whopping 35-degree F, let's say), start-up temperature will be around 140-degrees F. That noted, I start the engine and always wait for the oil to circulate sufficiently before rolling. It will sometimes take from Fernley (home base) to four miles West on I-80 before the engine reaches thermostat temperature. During this entire time, I hold engine speed to no more than 1,500 rpm under light throttle load. I expect this diesel engine to last for 500,000 miles, enough to bury the initial cost difference over a gasoline engine—and also to save a small fortune through fuel mileage gains over that number of miles. So, summer does bring better fuel efficiency. In my case, I've also switched to GDiesel, a natural gas altered fuel. (See my coverage of GDiesel in an article and HD video interview at the magazine.) By breaking down long chain molecules to more combustible form, this fuel does deliver mileage gains. Even better, I do not engulf other motorists in soot when I launch into the throttle during passing. Yes, my truck's exhaust, even without the later catalytic converter and exhaust stream additives, is clean, without visible smoke—black or white. While some clean-up can be produced through ECM programming, that's only to a degree. I use GDiesel and avoid mixing it with conventional low-sulfur fuel. (GDiesel is actually the very same low-sulfur base fuel, reprocessed with a patented method. You can mix the two in a pinch.) Fortunately, I can make it to Moab from Fernley and back home on one fill of the main tank plus the 75 gallon auxiliary Transfer Flow tank in the bed. Thanks for the questions, Megatron...Others are welcome to jump into the discussion and share their experiences! Moses

Sounds like you've been busy and committed to a solution, JJ! I like your pursuit of a leak down tester; this will demystify the engine's condition and seek out a possible compression loss that could cause a misfire. Trust the tool will pay for itself on this engine work and other projects. I've had my Snap-On MT324 for decades and am always pleased with its pinpoint diagnosis. Your new codes do hint of a TPS switch problem. I had a specific TPS switch issue/code around 110K miles on our XJ Cherokee. I purchased an aftermarket Brand-X replacement, and it worked for a short time before causing a misfire string that resembled a short or burned wiring from the crankshaft position sensor. Anyway, I sourced a second TPS from AutoZone on a Sunday, their own "brand", installed it, and no trace of a problem since. Some offshore stuff works, sometimes not. As just one example, let's consider the oxygen sensor. For Jeep and other Chrysler products, I specifically recommend genuine Mopar or at least ND brand as a direct crossover. Denso was the OEM supplier to Chrysler, and oxygen sensors have very sensitive ohms feedback, heating functions and such. See my article, this also applies to other electronic components in the fuel-and-spark management system: http://www.4wdmechanix.com/Use-OEM-Mopar-Oxygen-Sensors!.html. I'd try a TPS, even though I'm set against "parts replacing" experiments. The TPS is a wear item and prone to fail long before your 250K miles on the TJ Wrangler. This would be the first order of business to see if the other two codes clear as well. You'll find the TPS easy to replace; think of it as a spring loaded voltage rheostat or potentiometer. The TPS fits one way with a slight tension as you install the switch and rotate it into position. Your TPS does not require a voltage calibration, it's a straightforward replacement. Exercise precaution with the aging plug connector. Make sure the O-ring seats properly. I use automotive dielectric grease on the plug connector contacts for a moisture barrier. Considering how many issues can begin with a defective TPS, this is a good place to start. It's actually good that you don't have several cylinders randomly showing misfire codes or acting up. That kind of issue is usually the PCM itself. In any case, let's go a step at a time. You might also run a continuity and voltage drop test on the injector plug at this nemesis #1 injector. See this Geo Tracker post and my reply for more details on voltage drop tests and electrical circuit testing: http://www.4wdmechanix.com/forums/topic/115-geo-tracker-sending-torque-converter-clutch-solenoid-code/. Use a good quality digital volt-ohmmeter for these tests. This approach will get results. I would also disconnect the plugs at the PCM carefully, inspect the contacts and clean them only as needed, using electrical contact cleaner. Use automotive dielectric grease for a moisture and corrosion barrier when reconnecting these plugs. Take your time with old connector clips and fragile lock release connections. Protect these plastic parts. Let us know how this progresses. I'm curious about the cylinder leak down results, too! Moses

Thanks for adding so much filler detail from your experience, Megatron! Rich now has a wealth of information. I back up everything you share here. 4.0L EFI is a must, the BBD carburetor on the 4.2L CJs and '87-'90 YJ drives an entire aftermarket in EFI conversions that cost an ample sum. And like you share, there's not that much mystery and no threat in electronic fuel and spark management these days. You're absolutely right about the 4.0L inline six conversion. At the magazine, I feature the welding and fit involved in converting a 2.5L YJ into a 4.0L. After the Jeep CJ era, AMC/Jeep and Chrysler decided to make unique frames for inline four- and six-cylinder engine applications. On AMC/Jeep CJ's, the V-8s, fours and inline sixes simply required different, bolt-in frame adapters. Actual frames were identical... Installing an inline six in place of a YJ or TJ Wrangler's four-cylinder engine is no less complex than a V-8 conversion—see the Advance Adapters 'LS' Chevy V-8 into a Wrangler. Four-cylinder YJ models make good candidates for a V-8, although the four-cylinder YJ's AX5 transmission does not meet the torque rating of an AX15. A V-8 into a four-cylinder chassis begs the use of a 4L60E or 700R4 automatic. Advance Adapters is your source for the conversion parts. Transmission wise, the YJ has the 904/999 Chrysler three-speed automatic without overdrive. The '91-'95 features an AX15 manual transmission behind the 4.0L inline six. It's a proven transmission that I detail in the 209-step, two part how-to rebuild article at the magazine. Good point about the axle housings for the lower (numerically higher) gears. This is a well taken point for those wanting 4.56 or 4.88 gears in their YJ Wrangler. These larger ring gears will only fit Dana 30 axles designed for OEM 3.73 or 4.10 gear sets and Dana 35 axles with 3.55, 3.73 and 4.11 OEM gears. (Yes, they did use a 4.10 front with a 4.11 rear axle. This is common for many 4x4s and has to do with axle design or, in some cases, the use of two manufacturers. These YJs all use Dana axles.) The YJ Wrangler featured at the magazine's tech how-to was originally a 2.5L TBI with the lower gear ratios that Megatron describes. Great description of tire needs. The YJ Wrangler project at the magazine is my son-in-law's '87 that I built up—lucky him, eh? We stayed with the 30 front and 35 rear, ARB Air Lockers at each end with Superior Axle shafts for "Super" status; 33" tires, 4.56:1 gears, and he's gone all over Moab and elsewhere. Think of it this way: Sure, both the Dana 35 and 30 are small, but when you're off-roading, the 231 transfer case delivers 50/50 torque split to the axles. The Dana 35 rear only needs to tolerate 1/2 the torque it gets when the Jeep is on the highway in 2WD high range! So, these axles will work as long as the axle tubes remain straight...An axle truss can help here. Megatron is right about the NP231, too. Durable for a chain drive transfer case, hardly a weak point! I cover the NP/NV231 transfer case rebuild and SYE kit install at the magazine if you want details on what we're talking about here. A reduction gear set for this transfer case can take low range down a notch for those oversized tires. Then there's the Atlas transfer case—the ultimate transfer case solution. For a stock 4.0L inline six, the NP231, in good condition, will last indefinitely. Parts are readily available for rebuilding. Megatron is pragmatic and right: The Dana 60 monster axle housings hang so low that any real ground clearance gain requires 40" diameter tires to accomplish! Megatron's 35" tires with a Dana 35 or 30 axle makes perfect sense for useful ground clearance. Strange how these 60s got beneath Wranglers and CJs in the first place. An AMC Model 20 or Dana 44 axle is more than enough. 60s are a lot of unsprung weight mass and very costly to build and adapt. Thanks, Megatron, you've sparked interest and inspired others to jump into this discussion! Moses