Do you have oil on the ends of the driveshaft where they enter the transmission? If you do, there is good possibilty that the seals are not doing their job properly and need replacing.
Smart Part Number
The smart part number for each seal is Q 0000460V000000000.
Accessing The Seals
Changing the seals is very easy, getting to them on the other hand isn't.
Check outthis page to see how to remove the driveshafts to access the seals.
Changing The Seals
Once the driveshafts have been removed, the outside edge of that hole is the seal.
Carefully lever the old seal out using a crowbar, screwdriver or long nose pliers.
Clean under where the seal was and the surrounding area, if you have any transmission
fluid handy, dab some in the groove the seal sits in and onto the seal itself.
Push the seal into place and make sure it is seated correctly. A rubber mallet works well.
Incorrectly seated seals will interfere with the refitting of the driveshaft.
While the driveshafts are out, give them a clean, inspect the reluctor rings and
consider painting them with hammerite to reduce the chance of corrosion.