Programming tire size

Disclaimer: Links on this page pointing to Amazon, eBay and other sites may include affiliate code. If you click them and make a purchase, we may earn a small commission.

stevespeed

Member
Joined
Sep 24, 2022
Posts
1
Reaction score
0
Location
Minnesota
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

FRF Addict
Joined
Jul 29, 2019
Posts
6,429
Reaction score
12,563
Location
Detroit
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

Full Access Member
Joined
Jul 2, 2021
Posts
184
Reaction score
160
Location
Seattle
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

Pudendum Inspector aka FORZDA 1
Joined
Mar 4, 2019
Posts
869
Reaction score
1,279
Location
Commivirginia
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”.
 
Top