I know...sounds strange right? Well it is. The rear breaks on my wife's car gradually started sounded like they were scrubbing last week. I thought it was because of all the rain we've had and the gravel driveway. I had time on Saturday to take a closer look and it looked like they had a case of chicken pox. There are "bumps" all over both rear rotors; the front ones are fine. They don't wobble, drive differently, breaking distance doesn't seem to have increased. Just noisy scrubbing. She's not a "hard driver" or ride the breaks. Any ideas?