Originally Posted by bigjae1976
If the E9X design is like the E46...for those who go to the track, you'll be changing those seals everytime you climb under the car. If you see the design of the seal, there is a spring on the side of the opening for the output flange. That spring holds the seal against the flange which creates the seal. That spring is not super tight and won't prevent all seepage. It does prevent your diff fluid from pouring out.
It's the same seal and I agreed the spring is very flimsy. Seems to be a common problem however many folks won't see it unless they track the car.