ok so im planning on stuffing a set of 35"s under the truck this week then taking it to ford to have the spedo recalibrated. does anyone know the rev per mile for this size of tire or if there a calculator somewhere i can get it to reprogram my sct tune for the new tires. also since i will have the speedo adjusted do i need to enter the rev per mile on the tunes from now on?

 

I believe it is 598 rev per mile. I think tirerack.com lists it.

edit:

http://www.tirerack.com/tires/Spec.j...el=Mud-Terrain T/A KM2&partnum=175QR6KM2RWL&vehicleSearch=false&fromC ompare1=yes