do you need a key to drain and fill the transmission and the differential or just the transmission??

Most of the real cars have 3 differentials.
What model is yours?

Are you refferinig to car key ot to a wrench?

What is the problem, please provide specifics.

not sure on the automatic (id have that done at the dealership or independent shop since its a PITA) but teh 5 speed has a special tamper proof bit that you can pick up at ECStuning and the fill plug is a 17mm hex socket. ther rear diff uses a 10mm hex socket for the fill and drain plug
heres the diy for the tranny
http://www.audiforums.com/m_156758/tm.htm
and the rear diff
http://www.audiworld.com/tech/misc33.shtml

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