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When i bought my 1994 Dakota, i noticed that the fan shroud was missing.  They had rigged an overflow bottle on the core support. When i tried to put a new fan shroud on it hit the fan, so after some searching, i found that the frame was bent right behind where the core support mounts to the frame, which in turn pushed the radiator and core support back a bit.

 

The reason i didn't notice it at first was because they had also made sure to realign the headlights, as well as replace the grill, so all i noticed was that the bumper was bent in. The bend is in front of where the front suspension mounts to, and after talking to a frame shop and alignment shops, the bend won't affect normal driving, and according to them, it isn't critical that it even be repaired.

 

But i don't like having the overflow bottle mounted with bungee cords and zip ties, plus i have plans to eventually install a tube style bumper with a hidden winch, and with the frame bent like it is, the bumper won't attach properly. The frame shop wants what i consider an extremely large amount of money just to pull the frame back, so, after talking to a couple people, their suggestion is to heat up the frame where the bend is, and straighten it back out. My concern is, would heating up that area of the frame stress the metal to where it would weaken it?

 

Also, is it possible the frame would just bend again over time? I don't want to straighten out the frame, only to put undue stress on the new bumper from the frame trying to bend again. I have attached a pic of where the frame is bent. The black piece in the pic is the bottom of the core support where it meets the frame.

 

post-40-0-81898400-1377561654_thumb.jpg

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i've dealt with broken/cracked frames, but bent, dunno.  would imagine once it is straightened out, some plating/bracing is in order to reinforce the weak spot.

 

why not just run it as is?  issues w/ early tire wear?  this might be  the death penalty for a vehicle and you will chase all sorts of issues compensating for the damage.  might it be easier in the long run to sell it and start fresh?

 

good luck. 

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From your photo, it appears that the compressed frame section collapsed in the designed "crush zone".  Like the frame and alignment shops, I agree that this is neither structurally nor dynamically a problem for the suspension or front power system.  However, I see your point very clearly about the need for radiator and shroud alignment and adding an aftermarket front bumper.  

 

From what you describe, biggman100, the front bumper "looks" like it's in the right position, though that's surprising with the crush at the frame horn.  Alignment of the bumper does have some latitude with the bumper bracket slots.

 

In any case, is there an air bag system on the truck?  Do you need to be concerned about air bag sensors being damaged?  If not, there are a few options:

 

1) Pull the frame horn back to its original position as closely as possible and reinforce the reshaped section.  The frame horn would then have the original damage plus the pull to contend with, which does impact the integrity of the metal.  In the trade, the term is "memory", suggesting that the horn would readily collapsed to the crushed position with any impact or force—including an odd-angle winch pull.  For that reason, even if the horn gets tugged to shape, I would create a reinforcement repair patch to put over the area, approximately the thickness of the frame horn.  My welds would be MIG (most likely, using ER70S-6 0.035" wire) or TIG (unlikely, requires spotlessly clean, oxidation free metal).  I would stitch weld or make a diamond or fish plate patch to avoid risk of linear stress points and tearing of the metal alongside the welds.

 

2) If the metal, despite being crushed, is stable and aligned closely enough, you could modify the planned winch-mount bumper creatively at its mounting bracket on this side.  You would "square-up" the bumper with the body at the bent frame horn's bumper bracket...The crushed frame horn is one compression and would likely stay put, especially with the hefty winch bumper acting as a forward "cross-member".  By doing this, the likelihood of the frame horn deforming further, or wanting to pull forward, would be no greater than the amount of force the frame shop claims is necessary to "pull" that horn straight.

 

In many ways, frame material is similar to other plate or even sheet steel.  Imagine a piece of sheet metal being crushed, then either pulled straight or heated and pulled straight.  In either case, the metal at this point is weaker than when originally formed or rolled.  We know from experience that if we bend and work sheet metal back and forth, it quickly breaks down, "fatigues" and shears.

 

Closer to home, another example of this would be an early Jeep MB or CJ Jeep frame that was flexible C-channel and had riveted cross members.  We considered these frames part of the "suspension", as they twisted substantially from end to end.  Even the AMC era CJ frames flexed considerably.  I once held the end of a new, bare CJ-7 frame while Jon Compton at Border Parts held the other end:  We were able to twist that frame nearly a foot end-to-end.

 

Vintage Jeep 4x4s that have been "trail beaten hard and put away wet" almost always exhibit signs of frame cracking or repairs.  This trend lasted through the 1975 CJs.  Beginning in 1976, Jeep began building stiffer frames, fully welded and boxed, and frame survival got much better...

 

Modern vehicles, including the Jeep Wranglers and your Dakota, do have more rigid frames.  The new strategy is a rigid frame with all handling and tuning in the suspension members and steering system.  That said, your truck has stout frame horn material that took a good shot, collapsed, and would be happy to stay there.  If possible, you might build a relocation bracket for the radiator to restore the core support location.  This should not take much effort unless the crush in the frame horn creates an obstruction.

 

We can discuss this further, including details on a proper patch reinforcement, relocation brackets, welding technique and such.  Your photo is helpful, I "got the visual" immediately.

 

Moses

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Rarecj8, actually, because the bend is in front of the front suspension attachment points, it doesn't hurt the alignment or tire wear at all. I had to replace the idler arm, pitman arm, shocks, and right inner tie rod end, and after it was done, i had an alignment done, and the shop said there wasn't any issue with getting the alignment straight at all, and since they did it, the truck is perfectly straight with no wander, and before the alignment, there was considerable wandering from the front.

 

The reason i want to pull the frame back straight is simply because of the fan shroud issue, and the winch and tube bumper, which i already have, but the new bumper wont line up good enough to put it on, until i pull the frame out some. The fan shroud is an issue, because the overflow bottle attaches to the shroud, and not to the core support or inner fender, and right now my overflow bottle is a gallon milk jug that is attached with zip ties and bungee cords, and i would like to remedy that.

 

Now, about selling the truck and starting over, that isn't always a viable option, at least for this truck. The reason being, NY uses salt on the roads in the winter, and there aren't a lot of 2nd generation (1991-1996) Dakotas left that aren't all rotted away. I actually drove 150 or so miles south, into southern PA to find this one, but in the northeast, those trucks are getting harder to find. When it comes to pick ups, the 2nd gen dakota (i own 4 of them) is about the only truck i prefer to drive, so even if the frame wasn't fixable in any way, and did cause unrepairable issues, some will scratch their head and say why bother, but i would go to a salvage yard where i know i could get one rust free, and just replace the frame, before i would get rid of the truck. I have a 1991 Dakota that 2 years ago i did replace the frame on, and even as big a job as it is, it was worth it to me.

 

Moses, the truck does have an airbag, but right after i got it and found the damage, i had it checked by a local dealer. As you know, i have small children, and the last thing i need is for an airbag to accidentally go off with one of them in the truck (airbag systems make me nervous, after some of the things i have seen happen with them at a body shop i worked for). The bumper on it looked like it was straight, except for a small bend in it, because before i got it, the guy i bought it from took the bumper off, bent the bumper mount, and put it back on so it looked straight. I hadn't thought of reinforcing the frame, but that does make sense, especially since i plan on adding a winch to pull logs with. The guy im having do the frame work does do welding as well, so having him weld in a reinforcement shouldn't be an issue. The crush in the frame doesn't seem to cause any kind of obstruction in any way, or any driveability issues at all. Since i bought the truck and put it back to what i call "road worthy" status, such as the aforementioned front end parts, alignment, brakes, tune up, the usual neglect work, i have put 2500 miles on it, and it runs and drives just fine with no issues.

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The truck sounds safe and drivable, you've taken all of the safety concerns into account, including air bags.  If square on a four-wheel alignment, the truck's issues narrow down to the radiator and core support, the ability and means for mounting a winch bumper, and keeping the truck cosmetically square. 

 

Biggman100...I did notice the rust on the frame horn and sized it up as less than you typically see in salted road, Rust Belt regions.  Obviously, there's a life limit to your vehicles, including the frames that eventually rust away with the bodies.  (Gee, a perpetual market for new trucks!)  RareCJ8 and I are spoiled, we share stories about places at semi-arid Nevada where 100-year-old car frames and bodies rest peacefully in the sagebrush, a coating of harmless surface rust for patina.

 

I don't think the crush in the frame horn is going anywhere, and if you can be sure of the winch mount's integrity and "customize" its fit at that crushed frame horn, this should work.  Beefing the frame up at the damaged area would be good insurance.  The priorities are safe tracking, steering and brakes, maintaining wheel alignment, and safety for all occupants—which you address.

 

Moses

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Moses, you are absolutely right about vehicles from the rust belt. The 2nd generation Dakota is getting harder and harder to find in the northeast, due mainly to severe rust issues, and not much of a following for them. Common problems are rotted cab mounts, and rotting in the frame around the rear spring mounts. I was fortunate to find this one where i did, in the shape i did. I searched for several months for one that wasn't falling apart, and that was also a 5 speed. My other 3 are all automatic, only one of which i would trust to ever drive on the road, and that is because i replaced the frame, which was completely sandblasted and powder coated, and also rust proofed the underside of the cab and bed, but, as that is a 1 year only vehicle and has a couple major transmission issues, we only use it as an around here work vehicle, until i either upgrade to a newer transmission and engine, or have the one in it rebuilt.

 

Next spring, i plan to completely strip the 94, and powder coat the frame, and basically do the same thing i did on the 91, which is why im looking now at the best option for the existing frame. I do know of a place i can get a rust free frame, but that takes a 3 day trip, including a day stripping the other truck, which is what i did on the 91, so id like to avoid that this time if i can.

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I should clarify one thing. The winch and bumper i plan on using aren't actually new. i keep saying they are, but what i mean is they will be a new addition to the 94, but were originally mounted to the 91, and i only took it off to put on this truck because i don't use the 91 on the road anymore, and i have to travel almost 45 miles to help my step dad recover logs for their wood stove. With that said, i tried to mount the bumper on the 94, but because of the bend in the frame, the bumper wants to push the grill back, and i tried to be a little forceful and shove the bumper back the last 1/2 inch or so, and it cracked the bottom of the grill, and still wouldn't allow the bolts to line up right. Because of what i plan on using it for, i don't like the idea of just adding an extension to the bumper to line it up properly, which someone else locally suggested, because im worried about that causing other issues. The new bumper did have adjustable mounts, but when i put it on the 91, i made the mistake of having the mounts welded to the bumper, so i don't have much room to play with there either.

 

I think my best bet, as you and Rarecj8 suggested, is once the truck is apart in the spring, bend the frame horn back, and then have a brace welded to the frame to strengthen it, so it is one less worry i have later on down the road.

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Have an insight to share about powder coating.  In the '80s, I built my first Land Cruiser FJ40 project vehicle for OFF-ROAD Magazine.  In the process, I began using powder coating on various restoration pieces, as Toyota was horrible in its lack of galvanizing on the FJ40s, and this one, fortunately, was a '76 from the West, essentially rust-free, and I wanted to keep it that way.

 

I became enchanted with the powder coating process, which at that time was increasing in popularity and finding its way into many aftermarket automotive parts.  In the process of exploring other anti-rust processes for a magazine article, I paid a visit to the National City shipyards.  At one shop, a well-informed supervisor told me flatly that they had stopped using powder coating on ship railings and decking.  As he explained, powder coat is rigid and thick enough that you will not see the usual "exfoliation" that occurs when rust grows from the inside outward. 

 

From their experience, he advised against using powder coating on vehicle frames in areas of the country where there is high humidity, salt air or salted roads.  The rust that can form on the inside will be invisible until, like the ship railings that collapsed unexpectedly, rust has completely eroded the metal, leaving nothing but the powder coat.  I took his advice and abandoned my enthusiasm for powder coating.  It does have its place, for sure, but not on ship railings, decks or vehicle frames subjected to salted roads...Following that discussion, which I shared with the readership, I continued to paint my vehicle frames.  Inspect the inside of your frame rails often, whether powder coated or not.

 

During that period, I installed a set of headers on the small-block Chevy V-8 (383 stroker motor) that went into the 'Cruiser.  The chrome was poor and when I asked around, the metal/flame spray process came up.  I had the headers blasted and flame sprayed with aluminum, which is a very interesting material and process.  Flame sprayed onto steel tubing and flanges, the aluminum quickly dissipates heat.  In addition to preventing rust as a coating, aluminum flame spraying can tolerate scratches on the surface.  The material creates a healing reaction around the scratch, which helps prevent rust formation. 

 

For headers, especially on a racing engine that requires service while hot (visualize changing spark plugs in the pits), the aluminum flame spray works very well, cooling down the surface of the headers rapidly.  (My most memorable automotive related burns were from headers and exhaust manifolds or header pipes.)  What doesn't work well is the insulating header or exhaust pipe heat wrap that traps condensation and heat, causing the pipes to rust through.  The end result is a leak much like the rust-through on a powder coated frame exposed to salted roads—from the inside and hidden from view.

 

Here is a link on flame spraying and other "thermal coatings":  http://en.wikipedia.org/wiki/Thermal_spraying.  As a Coast Guard trained diver, you'll also like this story, biggman100:  http://www.metalize.net/content/flame-sprayed-aluminum-coatings.  The article is about undersea structures, and the punch line regarding flame spray aluminum is, "FSA coatings have proved that they offer an excellent alternative for protecting subsea components, the major advantage being that the coating acts as both a tough barrier coating and a sacrificial anode."  The "sacrificial anode" is part of that healing and protective ability I described.

 

Moses

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Your comment about powder coating, and the unseen negative effects, also sounds like what a dry dock worker at Bethesda naval base told me in the mid 1990's. I asked why they were still slathering on gallons of anti-fouling paint, and he said that it was because the U.S. Navy, Coast Guard, and Army found that to be the best below the water line protection available for ocean going ships. It is interesting that you mention thermal coatings, as one of the largest thermal research facilities is in NY, at New York University at Stony Brook, and i know a couple guys who went to school there, and for awhile, that was all they talked about. Now both of them work for companies that do thermal coating in Texas.

 

Someone else mentioned using spray on bed liner type coating for the frame, but im concerned about that having a negative weight effect, which might in turn lower fuel mileage. The consensus so far, after the comments here, and what others said when i powder coated the frame in the other truck, is that it would be better to just sand blast it clean, primer and paint it.

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Many say that blast, clean, prime and paint make the best sense.  Eastwood Company has an arsenal of anti-rust tools, including POR15 and other agents that neutralize rust and even provide a paintable surface.  That might make sense in your area, too.

 

I would avoid heavy painting, as that's the same issue as powder coating.  The only vehicle I've owned with rust came from Chicago, it was an early '80s CJ-5 Jeep that became both a magazine project and included in my Jeep Owner's Bible.  Louie Russo, a competent body and fender expert at San Diego did the rust repair, and it was a chore.  The vehicle had only minor looking exfoliation at a small corner of the driver's tub side section.  That rusty paint turned out to be a sheet metal section that needed cutting out and replacing.  Scary stuff that salt rust.  I'm sorry your roads are salted, biggman100!

 

Moses

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A friend of mine got ahold of several gallons of POR15, at an estate auction. I have never used it, but after reading the container, that seems to me like it would be comparable to, or even better than paint. I'm still weighing that as a possible option, as he said that because of how much of it he has, and how much we do for each other, that it wouldn't cost me anything to get a gallon or two. My concerns are how long it will last overall, and how durable it is. I don't want to use that, only to have to paint it in a couple years anyway.

 

The salt isn't so much the issue in the northeast, its more based on lack of care. My 1988 Dakota, with 210000 miles, was bought from an older gentleman right near the NY/PA border about 10 years ago, and because he took the time to wash it frequently, and waxed it, and basically kept it clean, the only spot of rust it had when i got it was on the rear wheel wells, which were very easily fixed with sanding and repainting. For comparison, my wife's 1996 Subaru, with 109000 miles, was bought in northeast PA, and had a couple of pretty bad spots right above the rear wheels, that only showed up after i washed it the first time. 4x4 trucks here are the worst for rust, because people use them as winter vehicles and don't wash them, or do any rust prevention at all, which is why i go south to buy vehicles anymore.

 

The scariest part of it is NY and their lack of concern for rusty vehicles. In NY, as long as the frame isn't rusted 6 inches in front of or behind a suspension point, the rest of the frame can look like Swiss cheese, and it still passes inspection. My father in law has co-owned a repair shop for almost 30 years, and he has had trucks on the lift for inspection that have looked like they were ready to bend in half, but because where the suspension points are weren't rotted, he had to legally pass them. In Pa on the other hand, if there is any hole in the body or frame bigger than a dime, it wont pass inspection, so when a vehicle in PA starts to rust, they send them to NY to sell.

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I did read the story you posted the link to, and found it interesting on a few points. Besides being a trained rescue diver, i am also an apprentice machinist, or at least i was for awhile, and i see a lot of valid applications for thermal coatings, the main one being frame and underside vehicle protection, but if the manufacturers did that, then the vehicles would never rust out, and no one would be buying new ones. The one thing i found lacking though, was that they never specified how well the metal was protected under the "blisters", and whether any type of rust, even if it was just surface rust, was present. I have a friend who is a maintenance machinist on an oil rig in the gulf of Mexico. I talked to him last night, and he said every rig he has worked on, either in the gulf, or overseas, had been thermal coated below the waterline, but since that part of the rig isn't part of his job, he didn't know how well the coating held up.

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Biggman100...I'm not sure whether POR15 is intended as a "paint" or strictly as a rust converter.  If a converter only, it would require paint afterward.  Worth exploring in either case.

 

As for why OEMs don't thermal coat frames, I think cost is the issue.  This is a labor/time consuming process (could be robotized, I'm sure), and the equipment and materials would be costly.  Seems reserved for specialty applications in aircraft, space and naval environments. 

 

Automotive manufacturers have turned to aluminum castings and structural components, and frames are now hydro-formed and have specialized metallurgy.  Not sure whether these new frame forming processes and the accompanying metallurgy have more resistance to rust.  It would be interesting to explore whether there are any automotive applications of thermal coatings.

 

Moses

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Moses, according to the manufacturer, POR15 is intended as a replacement for paint, and SHOULDN'T be painted over. I finally got around to reading up on it on their website though, and after some of the cautions from their site, such as not letting even a drop of moisture to get in the can, and how easy it is to ruin it before use, im not sure if i want to bother with it. This is the link to their directions for using POR15: http://qr.absolutecoatings.com/QR-assets/downloads/POR15/POR-NoReadDirections.pdf

 

That direction sheet says only opaque paint should be applied over POR15, and not to mix paint or coloring to it. It also specifically states if you are perspiring, and one drop of sweat gets in the can, the can is ruined.

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Interesting...So, this is a rust converter and "paint" in itself.  How resistant is the surface to rust after curing, and how long does that prevent the formation of new rust? 

 

If you decide to paint the surface, does the POR15 need blasting?  What is the suggested use or "value" for this product, is it simply an alternative to blasting away rust?  Sounds like it would dramatically affect chemistry for any welding.

 

Thanks for researching and providing the link, biggman100!

 

Moses

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After talking to a few guys who have actually used POR15, they say dont use it if you intend to use any type of automotive paint over the top of it. The paint will eventually peel off, because POR15 is designed to convert the rust, seal the material, and "paint" it as well. 

 

A small, 2 person shop that has been in operation almost 40 years recommended Picklex 20 instead. He said that it not only converts the rust, but also seals the surface and preps it for any type of primer and paint you wish to use. After going to the Picklex website, i did find that they say you cant use any type of "self etching" primer with their product, but that any other paint and primer can be used over the top of Picklex 20, which they highly recommend as a finish step.

 

They also say you can apply paint without any sanding or prep work once the Picklex 20 has cured. Their website is http://picklex20.com/ for anyone who wishes to check it out. If you read the FAQ section at the site, it also says it can be directly welded to, and helps with splatter issues, as well as being a good base for powder coating, and thermal coating applications, as well as being able to be covered with heat paint, and ceramic paint, and can withstand a continous 2000 degree f.

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Wow, your comments about thermal coating and welding over the Picklex 20 is intriguing.  Welding is a "chemical" and heat process, and the Picklex 20 claim that it will not impact welding (presumably chemistry?) makes this stuff unique...Thanks for sharing, I'll follow up and explore the welding/chemistry side of the product!

 

Moses

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