245 to 265 Computer Recal

[tahoesub]

Has anyone switched from 245/75 16 to 265/75 16 and had the dealer recalibrate the computer. I would guess they could since both sizes are available from the factory. I have a 2003 1500 4x4 with a 4.8, and switched for 245 to 265. The dealer claims the calibrations are the same, so no need to recalibrate. I don't buy it, and my speedo is now off by about a mile every 30 miles. This has afffected my DIC, fuel computer, etc. Any help is appreciated.

[NWChevyGuy]

You are right. It is not the same calibration, and they can adjust for factory tire Sizes. This is what my dealer told me when I went from 245s to 315s. They were not able to help me because 315s aren't factory.

[Slowprocess]

Yes, it does need to be recal. When I went to my 17s and low pros, I used my superchips tuner to recal my computer for this. I would suggest going to another dealer if your current one won't do it. If the dealerships won't help you out, and you really want to fix this problem, I would suggest a unit such as The JET SCU 2000 (Speed Control Unit). This is a fairly inexpensive unit that does no more than allow you to set the computer for tire/gear changes, shift points, and removes the speed limit governor. It doesn't effect the air/fuel ratio such as other programmers, just a device made for applications such as yours( that's why its considerably cheaper).

http://www.martelbrothers.com/frame....ic/default.cfm