I've got a 04 Screw 4x4 w/ 255/70/17 and I am wanting to put on 285/70/17 with a 2" leveling kit. Do I need to get the speedo recalibrated? Can the local dealers do that? Thanks.

First on race day.

 

You don't have to. I never corrected mine. Your speedometer and odometer will just be off. The dealer can recalibrate yours to the largest size offered on the FX4's, which is almost 33 inches tall (275/65-18's I believe). This will be extremely close since your new tires are right at 33 inches. The other choice is to buy an aftermarket computer tuner (Superchips, Hypertech, etc) and do it yourself.