I have a 2000 Expedition with 33's. I noticed both rear axle seals are leaking and figured it would be a good time to do a gear swap too. I've always hated how sluggish my truck is since the tire swap. I know I'd have to do a gear swap on both differentials, but I'm wondering about what other parts I'd need because I've never done a gear swap on a vehicle.

I'm currently looking at ring and pinion (4.11s) for both diffs and a master overhaul kit for the rear (do I really need one for the front?). Is there anything else I'm forgetting?

My truck currently has 70k on the odometer if it matters.

Also, what should I expect to pay for the installation of the gears and a limited slip (rear)?

 

I would guess about $2000 parts and labor to regear both axles and add a LS or locker in the rear.