Adjust MPG calculations with tire size?

[Naveronski]

Originally Posted by LDB

Not sure if you can do it in an automatic setting in the system but you can keep a calculator handy and multiply the odometer number before putting in the distance traveled.

I could do that, if I wanted to use a "trip" odometer reading for each fill up. However, I'd really prefer to keep using the truck's actual odometer and only extrapolate the MPG numbers.