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Diff change instructions...


Jedi Trainee
I am pretty good with these cars...but this is something I have not ever done...

I am in need of some step by step instructions to changing the rear diff. I have changed the rear axels on the Bugeye to Winner's Circle and the double hubs...



Jedi Knight
Drain the oil out the plug on the bottom of the banjo.

Remove wheels, drums and axles as you did when you changed to the WC axles.

Remove the (4) bolts holding the drive shaft to the differentail.

Remove the bolt holding the Tee for the hard lines and flex line from the differential (some don't get rebolted over the years so this may not apply).

remove the (8) nuts securing the differential to the banjo.

Rock the differential to break the sealant, you may need a rubber mallet to help it along.

Clean the mating surface and install a new gasket (I don't use a gasket, just permatex #2 sealant - YMMV).

Install the new differential in the reverse order, reinstall axles and fill with gear oil. I don't top off the rear end fluid, I put in just enough so I can touch the level with mu pinky.

It isn't a bad job at all, just keep everything clean.


Jedi Trainee
Country flag
Any difference if you're changing the diff from a 4.2 to a 3.9?

Michael Oritt

Country flag
After step 6 of Chris's instructions I would add:

After removing the center section spray carb cleaner or the like into the axle tube from both ends and into the center housing, then pass a magnet around the drain hole to remove any metal bits.
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