I just did this job, along with rear wheel bearing/hub replacements on both sides of my 03 Explorer. I want to point out a few things that I disagree with, so that others might be aware of them. I'll also list generally what it takes to replace these seals.
First off, the disagree list:
Don't use a hammer to push the rear axles in thru the hub assembly. Doing that can damage the CV joints. The correct tool is a FWD Hub remover like this one:
http://www.otctools.com/products/detail.php?id=1699
CV joints are not made to be compressed under shock like that. Also don't use a chisel. You could damage the aluminum rear end housing, or the axle tripod. Use a block of 1x1 wood.
I've also noticed many people say a 36mm socket is what is needed. I used a 35mm socket. I believe that the 36 probably works, but is not the correct size. That should be a problem tightening it back up. Ok, so here's what I did (closely following Fords instructions):
1) Have someone put their foot on the brake while you remove the axle nut with a 35mm socket
2) Remove the tie rod bolt and nut
3) Remove the Ball joint bolt and nut
- Don't use a separator tool under the boots, or you will rip them.
4) Use the Hub separator to push the cv axle thru the hub
5) Swing the hub out of the way
6) Pop out the old axle using a 10" long block of 1x1 wood and a mini sledge hammer. Hit the axle tripod from the rear end side. Locate the block of wood from the front side of the rear end, or possibly the bottom side. The axle pops out easily.
7) Pull out the old seal. I tried a puller, but ended up using a very small flathead screwdriver to start the removal of the seal, and worked my way up to a regular flathead screwdriver. Take care not to damage the rear end housing with the screwdriver!!!
8) Remove the 2nd half of the seal from the CV axle. You will eliminate this part entirely when installing the newest version of the rear seal. Old seal = 2 pieces. New seal = 1 piece.
9) Polish up the CV axle, where the axle rides inside the seal after installation. Use really really fine sandpaper or polishing cloth.
10) Install the new circlip (comes with seal) on the axle
11) Reinstall axle. Follow Fords torque specs. I think the axle retaining nut is something like 211 ft lbs, but check that. It takes a big torque wrench to go that high. I had to buy one.
Please note that I actually pulled my knuckle completely off, and installed new wheel bearings/hubs. So my experience around step 5 or 6 might be slightly different than if you are just doing the axle seals.