Tranny acting different

[addkev]

I had thought of that, I need to research it and see what all is required.

 

[addkev]

I know that alot of people are running 31's with no problems, but for some reason my truck doesn't like them. I am wondering if I get the speedometer calibrated to the bigger tires would the problem stay gone.

 

[Robert]

Maybe the people running 31" tires without problems have regeared their speedometer. Either that or maybe the change wasn't drastic enough to throw out the computer. When I first went from 30" tires to my 32" tires my transmission shifted very oddly. I only drove it that way for a couple of days before I bought a new speedometer gear which put the shifting back to the original condition. If you had tires other than the 255 70R16 tires your transmission will shift quite differently than before the tires until you correct the computer for the proper tire size.

 

[addkev]

Yeah, that is the general consensus from everyone I have talked to. I found a dealer in the next town over that will recalibrate my PCM to the 31's for $70.