Correction - it's only the B1 cover that's leaking. I guess it's the B1, it's the front one on the passenger side, slightly smaller in diameter than the B2. It appears to be more accessible than the B2 but I'm still not sure if it can come off with the tranny in the car, and if so how it comes off. As Ben Stein, as the teacher in Ferris Bueller's Day Off asked - Anyone? Anyone?