Tools Required 

• Basic Sockets, Ratchets, and Wrenches 
• Seal Puller 
• Picks, drill, and other optional tools mentioned below
• Leather Mallet 
• New differential fluid 
• RTV sealant 
• New axle seals ($2.00 @ NAPA) 

2)  If it's a traction lock 3.73 like this one, pull the little pieces of traction lock clutches out of the bottom of the case (no, no time to replace the clutch pack).  The fill plug has a magnet on it too as I recall. 

3)  Now for the fun part, that pinion shaft has to come out to remove the axles...  Unscrew the cross bolt and discover that a 1/4" bolt in a differential does NOT work.  If yours isn't broken (yeah right), then skip to step 4, otherwise read on.  This is no ordinary bolt.  It is a 1/4" bolt with (I believe) a 5/16 head that is 2"? long.  It is only threaded for a half inch or so.  The fun part is getting the rest of it out.  If the broken piece has no threads on it, a magnet will probably work.  If, however, It was like this (and of course it will be), there are just enough threads to keep it in there.  Our particular bolt had a piece of thread about 45 degrees around it left on it.  The first thing we did was run out to the local NAPA store and buy out their screw extractors, and a small telescoping magnet.  While we were there, we looked through the racks and found that special bolt.  Interestingly enough it was listed as a part for GM differentials, not Ford.  We bought it anyhow, and sure enough it was the right one.  It also has a ton of red Loctite on it.  We then proceeded to spend countless hours playing with drill bits and screw extractors.  It is absolutely impossible to get a standard drill and bit at the proper angle to drill into the center of that bolt.  I did manage to nick the corner of it, which greatly simplified things later on.  After the screw extractor idea fell through, we placed a call to our local mechanic friend.  He called back to explain our options.

HOW TO GET IT OUT : 

• Option # 1)  Run to Sears, NAPA, whatever before they close and buy out their stock of picks.  Try every pick you can get your hands on to get the thing out. 
• Option # 2 (Somewhat dangerous) )  Take your trusty arc welder, get the thinnest welding rod that you can find, and get ready to fire it up.  DISCONNECT YOUR BATTERY CABLES SO YOU DON'T FRY THE COMPUTER.  Hold the rod against the piece of bolt, and quickly touch the ground to the explorer.  If you did it the right way, you should be able to unscrew the bolt with the welding rod.  If you messed up, start replacing differential parts now. 
• Option # 3)  If NOTHING else works, take a sledge hammer and the largest punch you have, and drive the pin out of the carrier.  NOTE that you will now need to buy a new carrier for your 8.8.  (If you do this, write a letter to Ford and thank them for putting a 1/4" bolt in your differential...). 

4)  Remove the pinion shaft, it should slide out easily now. 

5)  Push the axles towards the center of the differential.  They should move freely.  I would recommend replacing both axle seals to avoid repeating this process in the near future.  The C - clips should now be visible, so take a pair of needle-nosed pliars and carefully remove them.  These C - clips are VERY slippery, so be careful not to drop them.  As you are pulling them out, notice the orientation of the tiny black O-ring on the C - clip groove.  If you need to, replace the C - clips. 

6)  Pull the axles out and wipe them off, remembering which side is which.  An axle puller shouldn't be needed unless you have a serious problem in there. 

7)  Take your seal puller and insert it into the hole in the seal.  If you do not intend to replace the bearing in there, make the seal puller contacts ONLY the Axle Seal, not the bearing behind it.  Slowly use the slide-hammer to remove the seal. 

8)  Admire this seal.  As I said, ours were only $2.00 a piece, and managed to fry the breaks on one side, and cause countless hours of suffering (In my case at least). 

9)  Take your new seals and replace them in each side.  We used a leather mallet here so we would not destroy the new seal, I suggest you do the same.  In reality, you should have something that is the proper diameter to push the new seal in with.  I suggest a large 3/4" drive socket.  Of course I didn't bring those with me, so we used the old seal to hammer the new one in. 

10)  If your axles are OK, carefully replace them and push them all the way into the center. 

11)  Replace the C - clips, noting the position of the rubber O-ring.  Here it is handy to have another person pushing the axles back and forth until you have unobstructed accesss to the C -clip groove.  It is also handy to have a partner here WHO DOES NOT TURN THE AXLES.  If you do this by mistake, you will spend some time trying to "Get the damn side gears back into position," to quote Paul Gagnon.  He's right too, it's annoying.  When you have to turn the unit, do so buy turing the center section (yes, it's somewhat painful to do). 

12)  Pull the axles outward, the C -clips should stop axle travel at a certain point. 

13)  Replace the pinion shaft and screw in your new bolt.  Make sure it's the special aircraft grade 1000 titanium bolt that doesn't exist. 

14)  NOW you can turn your axles and make sure everything moves as it should. 

15)  Apply the proper type of RTV to your differential and replace the differential cover. 

I hope this makes your job a lot easier than ours was.  I would almost rather have taken my box of match sticks and set up a new ring and pinion...  Sorry there are no pictures, but if someone has any, feel free to add them and any other information to this write-up.