Originally Posted by TerrorJ2001
I'm assuming upgrading the tires to 31's would have no terrible effect on the stock axles besides losing some mpg. I had that setup on my XJ.
Upgrading the axles though - with my stock wheels/tires would increase my mpg?
(I'm thinking with no regard to the cost of upgrading axles off setting the savings in gas)
No mpg's saving for upgrading axles only strength. The gears can be changed inside of the axle's but were stating its not worth doing if you've got a 35 in back. If you look at it from the rear and it has a center bolt in the bottom of the diff cover... it's a d35c. If that bolt is offset from center it's a d44
If you go lower gears (higher number) you will have more torque i.e. the motor works the same but the wheels turn at a slower rate. Think of it like an 18 speed. Not necessarily worse on mpg's but not necessarily better.
3.73 for people only 10% offroad
4.10 for people only 25%
And yes you'll be fine with 31's on the d35c I beat mine for 9 yrs with big 31's