I have a 6" life and 35" tires and I need to upgrade my gears.

Whats the best gear for 35" tire...

I do mostly highway driving.

 

4.56 is pretty much your only option.... 4.10 would be good for highway but not worth the $$ because its not much of a change. 4.30 would be ideal but its not made for the front reverse cut 8.8

 

Mostly highway? 4.10s. It will put you back to a pretty much stock ratio.

4.56s if you're looking for performance, but they will run more RPMs on the highway = worse fuel mileage.

 

but if he already has 3.73s why spend the money only to go to 4.10s?.....

 

My truck just got done getting 4.56 gears front and rear with an auburn posi in the rear and what a difference! I love the gears I am getting close to stock gas mileage if I drive the speed limit. At 65 M.P.H. the rpms are at 1900-2000. I used to get about 100 miles to a quarter tank of gas. When I lifted it it would get about 60-75 miles to a quarter tank. I have a 6" lift and 35"s and the stock gears were 3.55 LS. Now with the gear swap I am getting 87-95 miles to a quarter tank, and that is with two quads in the back of the truck.

 

i would go 4.56's or not do it at all. from what everyone says 4.10's are worth the money, which for $700 i wouldn't waste my money for a minimal change. 4.56 will get you your power back and help your city mileage but stock gears will probly give you better highway unless where you live is hilly. then the 4.56's might help out and give you better. right now i have 35's and 3.73's and on flat highway i have averaged up to 18mpg and on hilly highway i have averaged as low as 9mpg

 

x2 on the 4.56's I am extremely happy with mine