2018 f250 6.7 "tire size/speedometer calibration"

[TWSUPERDUTY]

Hello, Does anyone know how to calibrate the speedo gauge on the 2017+ superduty? I have tried the VCM Scanner but cannot find it. Will I have to purchase all 8 of the credits to change it? It now has 40" tires so its off about 10 mph.
Thanks

[Yamaford]

I would use forscan. Software is free and the module is easy. I've never had much luck getting speedo correct with any other method on the 6.0. 6.7l trucks can do all kinds of fun stuff with the forscan.

[TWSUPERDUTY]

I will see if I can figure out a way to calibrate it for 40'' with forscan. I seen a way to calibrate it for 37 but not 40s yet anyways