Noise from the area you refer to could be 1) The center support bearing rubber isolation has degraded and the driveshaft should be inspected for same and repaired/replaced straightaway. 2) A subframe/differential rubber isolation mount failure. 3) Bad rear shock mounts. I strongly recommend you seek out someone to put the car up in the air on a lift and inspect it for the unsafe issues that I have just presented, you might want to tow it to your BMW service provider to accomplish the inspection, be safe, do not take chances.
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Friday, January 28th, 2011 AT 5:34 PM