I have recently fitted what was supposed to be a leak-free PAS box to my 90. 2 weeks after fitting, the bottom seal let go in a sudden, spectacular fashion and I boiled it down to the box having been kept in storage for quite a while. i replaced the bottom seal and all was fine for a few weeks. The leak is back and it's not just a few drops. I am inclined to blame the bottom seal again (due to possible pitting on the shaft as is usually the case) but I have realised that the leak is probably starting further up since the chassis leg is pretty wet. Are there other seals that are prone to failure?