BMW M5 Problem Report
BMW M5 Alignment/Tire Wear Issue Due to Worn Rear Lower Ball Joints
The rear lower ball joints may wear causing alignment and tire wear issues as a result of the excessive play in these joints. Our technicians tell us a 4wheel alignment should be performed after ball joint replacement.
I had similar issue but with top control arms. If ball joints truly worn out, you can grab tire (car off ground) at 3-9 o'clock or 12-6 o'clock position and push-pull. Tire/wheel will be loose and will move. With upper ball joints, you must replace entire control arm (labor won't be any more; in fact, may be cheaper). Don't know if same with lower. Must replace both sides even if only one bad. And do need 4-wheel alignment after repair. - Kronco