8.8" Track-Lok Rebuild
Procedure By
"MFE" of the Corral Forums
Parts:
Ford Part # M-4700-B
Rebuild Kit (Includes: Frictions, Steels, Shims, Modifier, Pin) $40
Ford Part # F3TZ-4214-A (Optional High Performance) $10
80w/90 Gear Oil (3 Quarts)
Procedure:
1. Jack up the rear end and support with
stands.
2. Loosen the
diff cover bolts, removing all but the top two so you don't take a
gear-oil bath
3. Pry the cover
loose and drain the rear into a pan.
4. When threat
of bathing is gone remove the top bolts and pull the cover off
5. Scrape/wipe
out the bottom of the diff.
6. Now is a good
time to soak the new clutch discs in friction modifier, the need to soak
for 20 minutes at least. If not friction
modifier, at least gear oil -- you don't want to put them in dry
7. The shaft
going through the center of the diff is called the pinion shaft. It's got
a lockbolt on one end. Undo the lockbolt and push the shaft out. You’ll
only want to push it in a little bit so you can still rotate the assembly
and pull it out toward you. There isn’t enough clearance to push it all
the way through or to turn the assembly if you’ve tried.
8. Remove the
wheels and brake drums, leave the other brake hardware alone. Push the
axles inward, and you'll see the c-clips that hold them in place. Remove
the clips and pull the axles out gently -- don't torque the bearings on
the way out and don't let the axles hang, just remove them.
9. Get a grip on
the s-spring and pull it out. You may need to punch it with a hammer to
get it started, and keep a damn good grip on it when you remove it you
don't want it zinging around.
10. The gears
you see are the pinion gears and the side gears, called spider gears.
Rotate things until the spider gears pop out, then pull the pinion gears
out too. Inspect for damage.
11. Now you can
simply slide the clutch packs out, use the tabs on the plates if
necessary. Make sure you get them all out including the shims.
12. Reinstall
the clutches and steels in the proper order, using a shim at least as
thick as the ones you removed. You want to use the thickest shim you can
while still being able to get the spider gears back in. Forget about using
the set-up tool and all the special measurements, if you can get the
spider gears back in you're all set. Note: Each clutch pack is made up of
a series of Frictions and Steels and in the factory order they go
F-S-S-F-S-S-F. However, if you re-use the best two of your old Frictions
in place of one of the new Steels you can re-stack them in an order that
makes the diff lock better, which is F-S-F-S-F-S-F, which is the same
number of total elements. You may have to trial assemble it a couple times
to get the right shim so it's just loose enough to get back together,
barely.
13. To get the
gears in, it helps to have a helper turn the now-temporarily-installed
driver's side axle while you lock the passenger-side pinion gear in place.
The spider gears will squeze into place. They are perfectly aligned when
you can get the pinion shaft back in.
14. Re-install
the s-spring. This can be a *****. Try holding it against its slot with a
pair of channel-locks to get it squeezed down a bit while prying it in
with a piece of 2X4 using the swaybar as a fulcrum. Alternately, do the
same but whack it with a mallet. It should pop in. If it doesn't, try
using a 1-1/2 inch hose clamp to squeeze the spring so you can insert it.
Then cut the clamp and slide it out.
15. Re-install
the axles by pushing them all the way in, installing the c-clips, and
pulling the axles back out against the clips which are now recessed in the
housing and locked in place.
16. Reinstall
the pinion shaft and make damn sure you put it in the right way so the new
lockbolt can be installed. And do not use the old lockbolt.
17. Use gasket
maker on the diff housing and reinstall the cover.
18. efi85gt
posted a terrific tip for filling the diff. Forget the fill plug. Let the
rear end drop as low as you can and remove the little vent cap on the top
of the right side axle tube. Clean the area around it carefully and you’ll
be able to fill it through this hole with a fraction of the stinky mess
you get when you use the “fill hole”. But you should still remove the fill
hole bolt so you know when to stop filling, which is as soon as it starts
to come out that hole. Wipe the tip of the bolt off, it's magnetic and the
silvery paste is metal shavings.
19. Fill the
housing until it comes out the fill hole and replace the plug.
20. Lower the
car back down and go enjoy your newfound traction.
If you have any questions about any of these procedures feel free to
contact me
HERE
