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Discussion Starter #1 (Edited)
It is time for me to rebuild my Diff, does anybody have and tips and hints. Where is the best place to get the new clutches from and how do I get the 1 extra clutch to upgrade the gripping power if the unit?

I found this here is there anything to add??

"Here ya go, and remember, thank MFE:

That said you can rebuild it yourself in an afternoon, like so:
It helps if you have a good manual but the instructions that come with
the kit are pretty good. The part number is F5AZ-4947-BA. It lists for a little over $60 at Ford but Mean Mustang Supply has it cheaper if you can wait. Get yourself a small fluid pump to reload the diff with, and get about 3 quarts of 80w-90 gear oil. If you
use synthetic you probably shouldn't use friction modifier. If you want absolute max trak-lok action and are willing to put up
with some unsettling noises from the rear end, don't use any modifier at all. It just makes the clutches more slippery so they
don't chatter. I chose to use it and I'm glad I did since this is my daily driver, autocrossed and dragraced for fun. Anyway, here
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.
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 bac 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.
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) Remove the fill bolt on the front drivers side of the housing, and wipe its tip off. It's magnetic and the silvery paste is metal
19) Fill the housing until it comes out the fill hole and replace the plug.

And you can increase the "breakaway torque" as Chris Neighbors describes below:
You can increase the "break-away" torque of the T-lok in a couple of ways:
1. When rebuilding, change the order and quantity of "packed" frictions. From the factory, the T-lok is
composed of three frictions and four steels, in F-S-S-F-S-S-F order. You can reuse one of your old
frictions (the best, of course), and pack F-S-F-S-F-S-F. Same number of elements, but eliminating
steel-steel interfaces.
2. Install F150 T-lok S-spring. Prices for the s-springs were in the $10-$12 range...
Also, when rebuilding, install the thickest shims that will allow you to rotate side gears back into diff
housing. Some will take .045's, others will take less. Don't worry if you have a .040" in one side, and
a thicker/thinner shim in the other, as long as that is the tighest set-up possible..."

Thanks, Dwayne
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