wastintime

So I think I have wasted way to much time in analysis paralysis. Hypertech has a 30 day guarantee and they and the others all provide about the same boost without the gauges. The other programmers with the gauges give more power but my truck is plenty powerful now with the tires, etc as is. So I ordered the programmer and will use some old tires for now to test things out. My theory is that I have power to go 70-75 towing now and empty its fine. I want to stay under 2000 RPM so I want to keep the big tires. Turns out that size BFG is 33.8" tall so they are big but the motor turns them fine. I am planning to go down to a 275/70 or 275/75=32.2 or 33 and little less aggressive tread. I want to go 285/70 but its iffy if that will still be to tall a tire. The problem is my tires are shot and all of this takes tires and time to figure out. So what I really wanted was someone in internet land to chime in and say "I did this and it was great" saving me the hassle. I feel with a bit more torque and tuning from the chip, that a small bump in tire size will be tolerated, fuel wise and the tires are cheaper so I can absorb the programmer into the cost savings. I ran some tire sizes through the calculator to correct for size vs stock: 275/70=32.2"=3.68 gearing 33 RPM difference 285/70=32.7"=3. 62 275/75=33.2"=3. 98 285/75=33.8"=3.40 134 It seems like the RPM difference was more with the new tires but not sure. I still can't believe that this little bit of difference is that big in the real world but.... I just cant stand the puny stock tires, any thoughts? ANYONE

So in theory the torque is still good on the dyno down low and more all around, then I may get away with it. Went to pismo and surprise we went through lots of fuel but guys hauling bigger loads did just as good so I know I have to fix this. My relatives have a 2 ton dodge and it gets terrible mileage with the low gears, lots of power though. I want to run a programmer that will provide gauges like an edge or all the others, any suggestions. I don't want to trust anything that I can't watch the pyro with. Any way it seems like this motor should take a taller tire easier and that more torque might even things out. I also felt like it would be better for flat out highway runs but didn't watch it much before the tire swap. As another little bit of talk. I run a lot of different equipment on and off highway and it is all running higher rpm motors and hotter temps now due to emissions I am told. We run 500 hp MercedesCat/? motors up to 21-2200 rpm all day at full load and expect no issues, crazy. Thanks

I may have caused confusion, I have the "06" in question and a "00" 1ton dually. Both have KM2 tires, both have less than stellar mileage figures. I left out the specifics but its a stock truck other than the tires that are specked out at 34.3" but really about 33 1/4" installed on stock rims. I did not re calibrate or chip, etc. I have 3.73 gears with an auto and it is fine other than towing through CA, I get poor mileage. The issue is it is to much rpm in 3rd while towing and to low of rpm in O.D. I did run into a very detailed discussion of yours after I posted this, causing more thought about size and width and rolling resistance along with rpm facts from cummins, but I still need to decide on: #1 swap to smaller tires -side note about mudders vs all terrain and rolling resistance #2 install a chip hoping to move the torque curve and shift points to accommodate the change or #3 live with it. Gear change or "gear vendor" is a lot of effort for some looks . Will a programmer get me by or do I need to go back to stock until I can change gears or get a gear vendor? I would like to keep the big tires and get by with a programmer to fix the issues above. I like the lower rpm with the bigger tires but I can see that its an issue.

I found your power steering and linkage discussions to be vital to my repairs. Everyone wanted to replace ball joints and things not needed. New tie rods and power steering box and its back to new. Thanks for the information. So I am in the middle of a tire sizing dilemma. Can you help with how much bigger than stock 265/70/17 tires I can get away with? I am running 285/75/17 KM2 on my 06 2500 now and mileage while towing is sub par as you describe. It is in the 20 mpg range at 70-75 MPH empty. I am only pulling my 25ft toyhauler to camp but it drops way down to 12 ish. So is there another option? If I run a programmer or injectors etc can I keep my big tires and get my mileage back? I should add that I have a 2000 dodge also with 4.10's so I could run big tires and that truck does about 16-18 at 65. So I try to keep RPM's down but it still is not right. I just want to run slightly bigger tires and towing with o.d. off is to much RPM for traveling. I can not get the cummins program to load up. Truck is stock other than big tires, FYI. Thanks