One problem related to suspension noise has been reported for the 2001 BMW Z3. The most recently reported issues are listed below.
I am the original owner of this auto. I noticed a noise coming from the rear of the vehicle on deceleration. Upon inspecting the car, I found that the rear sub frame was almost broker in half. This is the part the holds the entire rear suspension for the car. From research I'm finding out that this is a common problem with z-3 BMW's in what appears to be a flaw in their engineering. I was very shocked to see the damage and that if I would have continued to drive the car, very shortly the part would have failed, wiping out the whole rear suspension. I am amazed that this was not a recall item or that I was not even notified that this was a potential issue so that I could monitor this and catch it before a major failure.