I'm getting a set of tires for an 04 4x4 with a 4.6 and 3.55 gears. A buddy of mine really likes a set of Mastercraft Courser A/Ts on his 150, but they are only available in 265/70/17 instead of the 255/70/17 OE size. I normally pull a boat with the truck and would prefer not to lose too much gear. Does anyone have experience with this or a comparable increase in tire size? What, if any, difference would it make in the effective gearing? Would this now be the equivalent of a 3.31 or thereabouts, or is the difference negligible? Thanks.

 

just from what i have read around here... it will not make a noticeable difference... but i am no expert.

 

The 265/70/17 will be approximately .60" taller.

That would be the equivelent of having 3.48:1 gearing in the rear-end (which is a non-existant, theoretical rear-end ratio doing the math).

Realistically, you will never know the difference from the cab of the truck if you switch to the taller 265/70/17's. Plus you can get practically any light truck tire produced in that size...it's a very popular size.