Klack when parking backwards with steering wheel right impact

Day Together. Vehicle: 3.0 Diesel from 2006 with 109,000km. Tires: 275 35 20. All chassis parts are unchanged, my car received the TÜV without defects 3 months ago, Edit: also the vehicle was lowered by 16mm Maybe someone could help me here. The situation as follows: Driving to a parking lot. Brakes to vehicle stands still. Steering stroke to the right while in position R is slowly parked backwards. After about half a meter of return travel mi There is a dull, very light blow, as if you were driving over a small stone that breaks under the wheel. I noticed a similar thing a year ago when I was shunting. Recently after a long motorway ride, I parked the car, turned the steering wheel to the left while driving, while there were snarling squeaking noises from the front left. In another post, I reported that it was in front of the wheel. e left clacks and rumbles when bumps such as channel lids, slight tar damage etc. are run over. The damper position S or S2 minimizes the clacking clearly. Who could guess what this can be? Thank you very much for help. Uwe