iam thinkin of gettin some BFG AT 285/70/17 if it wont change my MPG alot, if it does, i'll just settle for the 265's....

 

I don't know about 17" tires on a 3rd gen, but I went from 285's on my '02 and dropped 3-4 mpg. That stinks!

 

Taller is better for millage .
Wider is worse for millage .

 

The LT285/70R17's are probably the more popular choice for replacement tires......a tad taller than stock without alot of power / mpg robbing properties. I run them on my '03 and have been pleased with the upgrade. The A/T style tread designs should also be more fuel efficient than the M/T style I run in the Cooper Discoverer STT's.

Greg

 

I switched to Cooper Discoverer STT's in 285's and lost 2-3 mpg's. I think if you don't run as agressive of a tread pattern you won't be hurt as much as me.
D

 

I put some 285's on my old chevy 3/4 ton 8.1 L and lost 3-4 mpg, sounds like it wont be as much on these trucks though, and I wouldnt think that it would be

 

Dont forget to adjust mileage from odometer reading because of taller tire before figuring mileage. Easiest way is to use a gps or compare mile markers on interstate to odometer.

 

After having the pinion factor reset to 634 for the 285s, I lost maybe .5-1mpg. I averaged 20.2 per the overhead on a 340 mile trip last weekend. My truck is stock.

 

I did a tire calc seach. What is the other numbers for your stock tire? If you are going from 265 70 17 to 285 70 17, it is going from a 32x10.4 to a 33x11.2 and you lose a little over 3%. If you usually get 20mpg you would lose .6 mpg.