Originally Posted by Windsor

I'm not up on the Edge and Gryphon, but I don't know why they wouldn't. There are several parameters that affect tire size, gear ratio and N/V (speed sensor calculation), that I know SCT programmers have access to. I think you'd see a negligable effect on gas mileage, but your truck should be back to the programmed OEM shift routines and converter lock/unlock schedules. There are other benefits from a programmer. In stock form, the OEM processor keeps the truck in closed loop too long when it otherwise should be in open loop. That alone provides a notable increase in performance.