Any step-by-step on rebuilding rear calipers appreciated-- including clever ways to keep from spilling brake fluid all over. I am replacing rotors and pads in rear and attempting to rebuild calipers in attempt to finally end squeal that lingers in the rear even after I release the brake pedal (sticking caliper?). Letting a little WD40 soak the caliper bolts tonight.
81 5sp "moosgrunmetallic"
Open bleeders and use clear hose to run fluid into bottle before removing caliper. Wish I'd done the last time... Or was it the time before that... I don't know might have been the last quattro...
Compressed air with the rubber tipped gun in the brake line hole to get the
piston out. Don't shoot it across the shop! Put a piece of wood in to catch
or a clamp. Then it is just clean, inspect, polish, New seals ( square cross
section in square groove, simple), reinsert piston careful not to skew and
stick, I use blue goo caliper assembly paste as it color coordinates and is
compatible with ATE super blue. Then the dust boot and metal clamp ring.
These are about as easy as calipers get. Clean all the external parts of the caliper where they slide with a wire brush and lube before putting it all back together. I also grease the face or the piston and any other contact points between moving parts so the brakes won't squeal being careful not to get any on the rotor or pad faces.
Oh yeah the 20° alignment thing. The piston face has one side that is slightly relieved. This faces the leading edge of the pad and is designed to relieve a tiny bit of pressure so that the pad wears more evenly. The 20° is in alignment with a radius line from the center of the axis of rotation. So that would be proceeding the radius line. It makes more sense if you are holding the caliper in position. There is a good diagram in the manual.