One problem related to suspension noise has been reported for the 2020 BMW Z4. The most recently reported issues are listed below.
Don't know what is causing it. There is major squeaking/whining/grinding noise if even a tiny bit of water gets in there and last couple days after that. And when you turn the steering wheel to the left the squeaking/whining gets louder. And when does do this the suspension if you hit even a small bump will bottom out and make grinding noises. BMW has looked at the car couple times first time they said there was rust. Second time they couldn't find anything wrong with it.