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any write ups on easiest way to replace rear end oil?

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#LS-378 - So many Porsche's, so little time....
If you have the stock rear end girdle you will need to remove the girdle to remove the old fluid. You'll need a new gasket also. When replacing the fluid consider Redline Lightweight Shockproof synthetic. Some of us have replaced the rear girdle with a unit that has a drain plug. The stock girdle only has a fill plug. The 'fill check' plug is on rear diff housing itself on the engine side of it. if you track the car it's a good idea to swap out the fluid regularly.


Save the dawn for your dishes!!!
here is the work shop manual link it has to be in there somewhere
you can go get you a haynes manual it will break it down pretty well too.

1. raise car so rear end is hanging down
2. drop one side of panhard bar to get it out of the way can just pop the diff cover leave the top two bolts in and just crack it other wise the fluid is going to go everywhere.
3. I take paper towels and soak up remaining fluid.
4.scrape of old gasket with razor blade on both the cover and the case
5. apply a bead of black silcone around the case making circles around the bolt holes. I think smooth it out with my finger.
6.install cover draw in bolts evenly torque to spec.
7. remove fill plug in the front drivers side section of the diff housing.
8.I use a sipon gun and suck it out of the bottles then push it in to the housing. do this till it just dribbles back out the hole.
9.reinstall plug. reinstall panhard bar clean up and your done.


What black silicone to use? I presume it needs to be high temp performance rated?

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