If the rear differential ratio in my 01 Navigator 2wd was changed from 3.73 to 3.08 or 3.31, what affect would it have on sensors, speedometer, anti-lock brakes, etc. ? Would it screw things up big time? Would a trip to a dealer be required to make adjustments to the computer program? Has anyone here ever done this? Not that I'm set on doing this but we hardly ever tow anything. And I know I should have considered the ratio before purchasing the vehicle. Just want to know what my options are.

 

Yes you will need to go to the dealer to have them reprogram your computer. not a problem, I had to have that done because of the 24in wheels i put on mine. they just reprogrammed it in about 15 min. now all is fine and the speedos right on.

 

hmm. this thread looks familiar!! lol.