tao

Last night, my Audi 100 gave me a horrible grinding noise from the left rear wheel. When I took off the wheel and examed what was going on, I found the outside of the brake disc was totally rusty (I used my hand to touch the inside, and it's smooth). Looks to me, that the outside pad hasn't touched the disk for quite a while, and I suspected that the inside pad may have worn out and gave the gridning noise. I am wondering if anyone know what could cause this pad malfunction problem? Shall I just change the pads or the disc as well? Do I have to change both wheels? Thank you very much!!!

beep-beep

The pins are under the rubber covers on the caliper carrier. The caliper is bolted to the pins with two bolts. These pins must move back and force if they don't - caliper will not move and only inside pad will apply preasure.
You will have to replace the brake caliper carrier(s) (~$40) each.

tao

The rusty guide pin is also my guess of the cause, feel good to have some one confirm my thought. For brake work, do I have to replace both rear wheels at the same time?

Thank you very much again!

A6Gary

carrier need not be repalced on the other wheel unless it also is frozen.

snowman '92 100

<img src="http://www.justboring.com/images/rusted%20caliper%20carrier.jpg" />