I bought a Trinity T1000 for my 03 ram 2500, to save a few MPG and change the parameters for tire size, and I just found out that the T1000 can not do it. Is there any tuner/programmer that will change tire size paramters of a 03 or is this hopeless? Thanks for the advice!

Smarty.

I agree, Smarty Jr is a good choice if your just after a little mileage bump.

i have a tuner its listed in my mods below, there is a setting for tire circumfrence but not sure if it acts as a speedo healer..?