Programming tire size

[stevespeed]

I am changing my tire size and my dealer says he cant program the computer for the speedometer to match the tires. That makes absolutely no sense to me. Are they right?

 

[FordTechOne]

Dealers are advised against attempting to modify programmable parameters. Wheel speed is a critical input to multiple safety related systems. Attempting programming will often also cause VID block corruption and related DTCs. Your best bet if to find an aftermarket programmer that is capable of changing that parameter.

 

[JorgesRaptor]

I am changing my tire size and my dealer says he cant program the computer for the speedometer to match the tires. That makes absolutely no sense to me. Are they right?

Depends on what year you have and what tire size you’re trying to use, I have the COBB tuner for my 2020 and I can change tire size on it if I went to 37s.

 

[TwizzleStix]

If you’re not into running an aftermarket tune, the FORScan software has capability to change many of these parameters. There’s a few threads on it. Just search here for “FORScan”.