Well im moving on to my next upgrade here in the coming months, figured id would ask you guys first before i ask my mechanic. Anyway she is on 5.5 lift now sitting on 35.x12.5.15s. She drives great and the hemifever 91 tuning sure gives it some extra *****. I really wanna improve the off the line acceleration and my overall throttle response. I'm still getting 12-13mpg which is pretty good considering the lift and tires, so thinking of changing my stock gears. So i'm thinking 4:10 would be ideal from the 3:55 i already have. Don't know a lot when it comes to swapping gears or if it would be worth it or not. I think it would be easier on my tranny though since i do a lot of climbing daily.

 

"Worth it" depends on what you want.

4:10's will put the engine RPM vs. speed back to stock values. If you do mostly around town driving, going to 4.56 wouldn't hurt you. That would bump RPM by about 200 or so at 60mph, in O/D. (tcc locked) The lower gears would give the engine/trans a bigger advantage trying to get the heavier tires rolling. Probably would have minimal effect on fuel economy.

 

im assuming it shifted correctly and you still had decent power? reason i ask is i want 35's once my new 33's wear out but i didnt want the expense of re gearing front and rear right away. if you drove with 3.55's ok i would think i would be good as well since mine has the awkward number 3.92's

 

In my experience going from stock 265/65/75 with 4.10s from same ratio but with 3.55s. My mileage went up my one or two mpgs. I live in a. Hilly area tho. If you live out west in a giant flat spot it woikd be a lil different. So I would always gear a little on the low side (higher number) vs the tall side (lower ratio)

 

Ya it has tons of power but you really have to get on it sometimes to get those initial turns on the big tires. I commute to work everyday but I don't go on the highway at all. My drive is through the mountains with lots of hills. I go on the freeway maybe once or twice a week but not far ??? I've pretty much done everything I can to make the engine power it's highest, it's just the extra weight bogging her down now.

 

If it was my truck I would install 4.56 gears and skip the 4.10's. Going with the lower gearing it will help to overcome the extra weight and rolling resistance of the larger tires plus the higher brick trying to push thru the air. You're not going to raise the RPM's that much going from 4.10 to 4.56. There won't be much if any difference in the price of the gear sets. Also while you're getting the gear swap done you might want to think about adding some type of traction aid device. For all around street and light off-road driving I suggest Tur Trac diffs.

 

I would also go with 4.56's with the 35's.