Travis, Most of these braking systems have a separate mechanical emergency/parking brake system. These are very similar to regular drum type brakes, only much smaller. Not designed to do much more than park or emergency use. These tiny brake shoes are located in the rear rotors. If you look at the front rotors and compare what you see to the rear rotors, you will see the difference. The rears have a much bigger hub area. (AKA mini drum). the shoes themselves are about 1 1/2 inches wide. They do have a self adjuster, but most of the time this device, unless kept clean and lubricated, doesn't work very well. In some cases however, they can malfunction and over adjust the shoes so they are subjected to excessive wear. I believe this is what you are dealing with. The self adjusting feature works when backing up. It's too bad that owner's manuals don't give better info on this system. Unless your car has a rather different setup, you have little shoes that are probably worn out and scraping on the drums. How well does the emergency/parking brake work? Either it doesn't work at all or it's too tight. A little test for you. Put the car in drive on a level road surface with no traffic. Get it up to about 5-10 miles per put it in neutral and then apply the park/emergency brake. That should tell the story. Good luck.. BTW, another possibility. When backing up, your pads may be getting cocked out of alignment and rubbing on the edge of the rotors. Not likely but possible.
1987 BMW 325
[This message has been edited by jeffsr (edited 04-17-2000).]