help diagnosing grumbling noise/vibration

[elemenohpee]

My 318is has a grumbly buzzing noise and slight vibration that feels like it's coming from the front. It's emphasized when I turn left and when I go over bumps.

It's only happens when the car's in gear. If I put in neutral, the noise and vibration completely goes away.

I originally thought it was either wheel bearings, cv joints, or the diff, but I'm wondering now if it could be the motor or transmission mounts?

[TobyB]

I'd eliminate the exhaust system hitting anything or being slightly loose first...

... then see if maybe the driver's the source of the grumbling...

<sorry, that was too easy>

t