Hanging rear caliper

[Ingo Rautenberg]

All this talk of stuck rear calipers had me checking mine when I replaced
the right rear tie rod.  After removing the calpier from the guide pins I
found the lower one to be somewhat resistant to movement (unlike the upper
pin) and upon removal totally dry with a dusting of rusty powder.
Curiously, could not locate any perforation of the rubber boot. Cleaned up
nicely with scouring pad (the type like sandpaper), squirted some BP Blaster
in the hole and worked the guide pin around, did the same again, and then
after the last cleanup greased up the guide pin (and the upper one as
preventive measure) and reassembled.  Got to use the Harbor Freight rear
brake piston retracting tool for the first time, and it made it very
painless compared to when I didn't have the tool.  An excellent addition to
one's tool box..  It's Item 40732-OVGA and they sell it for $40.  Not
Audi-specific, but it looks ike it has most every adapter one might need.

Ingo