[Stocker]

Originally Posted by mechanicalman

Everything you say points to the R side as you pumped fluid through it and still saw bubbles (sucking air into the fluid from the cylinder). If the shoes are wet, replace both rear brake cylinders and shoes. Surprised you didn't see a fluid leak or traces of it somewhere.

Agreed. I went through this last year, kept getting bubbles at the rear wheel cylinders. Turned out they were both bad but such a small amount of leakage that I never noticed it. New wheel cylinders did the trick.