Been tracking down leaks from my 1991 500SL tranny and just had a new pan, gasket and oil fill, however its still leaking from my overload pressure switch.

A couple of questions :

1). Do I need a new pressure switch or can I just change the O-Rings and are they available from the dealer as spares?

2). Can I do this without too much fluid loss? Or do I have to drop the fluid, and dare I re-use it? a fill these days is $100

Thanks,

Richard

__________________
1989 W124 300E
1991 R129 500SL