I looked for this thread but could not find, figured this would be the best place to post becouse it deals with tires, Now to the question i would like to put on toretion keys and maybe a 2 inch block in the rear so i could put on 285 75 16s or 295 75 16s and give the truck a better stanse but i do alot of highway miles and was wondering from those that have bigger tires, how bad do bigger tires hurt your milliage. Thanks

This has been gone over a few times before in other posts. General consensus is that you will lose 1 or 2 mpg going to a larger tire like that.

Because the tire is taller, your rpm's will drop on the highway by almost 200 rpm's at 65 mph. But because the contact patch is larger and the tire weighs more than stock and friction increases dramatically, you do lose a little in the fuel economy area.

The taller stance of the truck also increases the aerodynamic drag on the under carriage.