One problem related to suspension noise has been reported for the 2009 BMW X3. The most recently reported issues are listed below.
Loud rattle from rear suspension, sounded like loose shock tower. Took to dealer, both rear suspension springs were broken. I avoid all road hazards and do not 'beat' my cars. BMW service advisor had a broken spring on her desk to explain the issue. It happens that often. Repair cost me $987. 38. I call manufacturer defect.