This is an old thread, but I thought I'll add some knowledge to the matter. I have mine shot and actually noticed this when changing the shocks. I decided to order the control arm also, cause it was cheap and I could rebuild it with a new bushing for future use. But, the bushing being shot is the outer one, which is attached to the wheel carrier and it needs to be pressed/hammered away. I have actually had a C Mercedes with the same rear suspension, so I know that this is the first part to fail in the rear suspension.