This may be the spring pad problem
 

Please check this out, see if it can fix your problem and please post feedback here.


If anyone can show me how to take the picture from word doc, I can show the pics from the reference guide. I took the screen shot from the computer and paste them to doc.


Quote from BMW Repair reference:



E53



Complaint:
Rattling noises from the area axle



Causes:
Lower spring support for the rear coil springs comes loose from mounting. This means coil springs is no longer guided and causes rattling noises.

It isnt so much a rattling noise, but a horrible squeak noise when turns or made and the such

Lower the noise
 

Action: bought the spring pads from dealer and have a mechanic replace the pads.

Result: lower the squeaking noise, yet not enough to eliminate it, still hear when driving in highway.

Following thoughts: probably should have replaced the whole thing: springs, upper pads, lower pads, guiding caps, nuts and bolts.

Try to spray rear bolt joint with WD40. Did it yesterday and noise is gone.