Hi guys, I have a 2001 Supercrew 4x4 with the 5.4 and the 3.55 (NOT LIMITED SLIP) rear end. If I put 4.10 gears in it will I notice a difference in the torque? How hard is this for me to do myself having never done gears before? How much will it cost me? also will I take a big hit in gas mileage? Also will I have to do the front and the rear since its a 4x4?

Thanks,
Wes

 

You should notice a big difference in the way you truck responds if you go from 3.55 to 4.10s. Milage would probably suffer a little bit also. With a 4x4, you will have to change the front and rear gears. They must be the same on a 4x4 or you will cause the transfer case to bind up and break. That is the reason that you have to run the same size tires, front and rear, on a 4x4. This is not a project you want to attempt yourself. It takes a lot of experience and skill to set up the ring and pinion gears properly or there will be all sorts of problems ranging from noise to breakage. In fact most experienced mechanics in my area will try to discourage people from swapping gears. You deffinately need to find a mechanic that specializes in ring and pinion work. I am sure the labor will vary from area to area. You should be able to get a good idea on the parts cost from catalogs and magazine adds. Just remember you need two sets of ring and pinion gears and two rebuild kits (seals, gaskets and such).

 

I'll second Wandell on this...you don't want to try and do this yourself if you've never done gears before.

To date, I've done 2 full sets of gears--one bad and one good...I couldn't get the set-up correct on the first--ended up taking it to a gear shop.

Didn't want to be beat so I did the regear on my Grand Cherokee going from 3.73 to 4.10--performed great. Now the kicker--1 full day and 2 half days (from 4:00 pm til 10:00 pm) of hell to get the pinion depth, contact pattern and backlash correct complete with countless R&R's, measuring, skin loss, blood loss, temper loss and curse words. I will never do another gear swap again!!

If you pay to get it done, it should run around $1200-1400 for gears, install kit and installation. Be sure they give you at least a one year/unlimited mileage warranty--just in case.