We have an 02 Dodge 2500 that we put slightly oversized tires on which put the speedometer off by about 2.5 mph according to my two GPS units used. I have a 04 Exp 4-wheel drive that I'm wondering how the addition of over oversized tires bothers all the computers. The truck has advancetrak(sp) which I assume also includes that infuriating traction control system. As a side rant... As a person that is still used to using the foot feed to control the vehicle, my blood pressure rises when that dad-burned traction management system shuts off engine power and applies the brakes when I need the tire speed the most! Pressing the delicate little button to shut it off shows that it turns off but nothing changes. So stuck I get on wet grass in the hay field. And that's in straight 4H. Anyway, this question is about the speed sensors not my rant on the traction control. How is the engine management systems reprogrammed for larger tires and can it be done without sending half a weeks wages home with a dealer mechanic?
Bumping this post, planning on putting big ol' tires on my '04 eventually and would like to know a cheap method too. Anyone know if you can do it via one of those scanner tools? Was considering buying one of those "universal" ones that works on multiple brands, but not sure it'll be worth the expense
All I can say about a scanner tool is that I have an Actron Autoscanner Plus CP9680. Not sophisticated enough to work inside the computers other than to read and erase codes. It has graphing and codes for many makes and such but no reprogramming capabilities. The most expensive Autoscanner they make in a handheld is nearly $400 but it only includes more foreign vehicle tests and still no programming abilities from what I can tell. It seems that a laptop style analyzer will be required. I don't have a laptop so that's out of my area of knowledge. That's not to say their aren't other companies that make hand helds that won't do reprogramming however. I think the cheapest way is to buy a tuning kit or chip. I haven't looked at them myself for this truck; with 230K on the meter I don't think it has much life left in it so it's not worth risking adding more stress with more horsepower which I would likely do.
Hi Randy, As of my last checkup I can tell that FORScan is a viable option to changing tire sizes as long as you have the right mod information. You can always get a Chinese versions of FORD VCM adapter (there are many). Many had reported success with those using IDS. VXDIAG has a software version of it (VCXNANO) All that said these two solutions can be highly risky if you don't know what you doing and possibly brick your module. There are dedicated forums where many have prior experience and are happy to help. FORScan would run you around $50 with a really good adapter. VCX NANO will run around $100 and long delivery date. Good Luck
Just wondering if you spoke standard American English? The only part I understood was - "Good Luck". Hahahaha I certainly am not computer savvy enough to risk intrusion into my trucks ECM's. I'd pay the higher price for a preprogrammed unit or 'chip' if it came right down to it. Regardless, at least this brings up options that others may be interested in that have more interest in changing the pre-programmed tire sizes and much more. Thanks!
Hey Randy. Sorry about the confusion. In order to change the tire size properly there is a need for the right software (FORScan, IDS) and the right Hardware (VCXNANO, OBD R/W capable), one that is able to communicate back and forward with the ability to modify some data on the vehicle Modules. With Advancetrac its quite a must since the system is so embedded in many parts of the car and this data is relevant in the way it calculates the response when emergency happens. I dont believe nor I have yet to see any product on the marked that is a plug and play "chip" since one have to modify data in the relevant modules. If any -- a good way to go at it with no messing around is to find a dealership and pay the time it takes them to reprogram the right modules to the right tire size. With the dealership level computer that should not take more than an hourly rate. I hope that helps. Good luck (and i hope you understood more than that this time.) Unfortunately it seems like the Expy community is not as big as others (the f-150 especially) on mods and tweaks in that level so information is hard to find.
