When my center bearing failed...
...the driveshaft would grind against the heat shield above the resonator/exhaust. It would grind loudest when decelerating.
And quiet down mostly on accelleration. All center bearing failures don't sound the same, it depends on how bad it is. Its a $30 part and a few hours of labor, not real hard, just time consuming.
That would be the most common failure anyway, could be the other things people have mentioned also.

Originally Posted by
pyro
explain what your grinding noise was. was it only when starting from a stop? I think it may be the same thing with me (thats what my firend said) also i think the trans mounts could be shot to. Ill give it alook
DanH
1989 535iA 254k Miles
1992 535iM 330k Miles