My right front lower control arm failed at 50K miles and is a common problem on these vehicles. I was told my CPO warranty wouldn't cover it, but my brochure indicated bushings were covered so they good willed it. Shortly after that my upper right strut tower bushing went out, making a loud banging sound whenever I hit a small bump or stopped hard. I have a feeling that when the right control arm was reassembled, it was over tightened. BMW wouldn't cover that, I ending up replacing both upper and lower strut tower bushings, another common suspension problem on X5 E70 models.