I gave the answer. The AS BUILT data from Ford will have the correct tire circumference number you are looking for because your truck was equipped with 275/60/20 tires.
Go to this website and enter your VIN and you can download the BCM AS BUILT data that your truck left the factory with.
https://www.motorcraftservice.com/AsBuilt

I am not hurt. I have just never paid much attention to any model years newer then 2016. I'm just plain old ignorant to the factory tire sizes of the newer models.

 

charming fellow!

 

The TCM uses an adaptive learn strategy, you should be able to just reset the shift tables. It will drive like absolute **** for a week if you do this, but the TCM algorithm will adjust itself. The parameters which would not automatically calibrate would be in other modules like your speedo and dynamic rear view backup guide lines https://mobdro.bio/ .

 

Ok, max I could go up was 2675
Speedo is off 2mph on low speed and high speed 3mpg
275/60/20

 

So what are you looking for?
- Factory tire circumference in mm - what did the AS BUILT you downloaded from Ford say? That's your answer.
OR
- Correct your speedo? If so, more info needed. What was your factory tire size and lines 726-15-01 and 02 from your factory AS BUILT? What is your current tire size and gear ratio?