Hi All.
Dealer told me that my A4 2012 quattro sedan has a leaky rear differential and need a replacement. It is expensive. Is anyone knows if diff can be re-sealed? Is there a test to verify if diff has a problem or it's fine? Is there an aftermarket or rebuilt differentials?
Thanks.

 

Not really knowledgable about the Audi rear diffs. I would ask where it is leaking from and if that is a gasket issue. If so it should be fairly inexpensive repair. Unless the gears are chewed up from lack of fluid which would cost more to repair. I would take it to a trusted shop and have them take a look.

Also, did they say replacement or repair? That makes a big difference. Find it odd that it would need to be replaced.