[s-cars] rear brake failure again... (long)

[James Bowes]

ok, here's an interesting one...

put on the BIRA system 3 brakes in May (1995.5 S6 avant), and soon 
thereafter I found out that my rear brake on the drivers side was not only 
worn out, but needed to be completely replaced. The diagnosis was that there 
was a small amount of rust on the cylinder, thus making it impossible to 
retract. Every time the brake was applied, it pushed it a little further out 
with no way to retract. It machined away the whole rotor very quickly.

I replaced both rear rotors and both rear calipers with rebuilt ones. We 
found that the parking brake cable was sticking on one side, so we cut the 
cable on that side with plans to replace the whole cable later when I did my 
exhaust.

Now I'm getting the same "ringing" noise from the same rear brake. I think I 
might have the same problem as before, after only a few months. Haven't had 
a chance to tear it all down yet, I'll do it this weekend and check.

I think my initial diagnosis about the rust on the caliper may have been a 
red herring. Could it be that there is a different reason for this behavior 
from the rear brake? Would a pinched SS line in the rear cause this?

Any advice would be helpful.. I'm going nuts here trying to figure out a way 
to prevent a THIRD failure