I have done the search. I have read "At wits end" http://www.oilburners.net/threads/brake-problem-at-witts-end.78362/#post-927148 and I have the same sort of problem. The truck ruined the right rear drum. Bought shoes, bought wheel cylinders (bleeders stuck, cheap enough, just replace) bought one drum. Other drum is serviceable. Before I started this the brake problem was there. Good firm pedal with truck off and vacuum booster drained of vacuum. Start truck up, push brake pedal and pedal slowly sinks to almost the floor. So I replace the shoes, free up the adjusters. Find the parking brake actuators are sticking. Free those up. Find AZ sold me two left wheel cylinders. So I will replace only one at this time. Clean, mount brake shoes, adjust shoes out until the drum will not slide on and then back off a few clicks until the drums will slide on. Bleed brakes. The low sinking pedal is still there when running. Replace master cylinder. Low sinking pedal is still there when running. Desperate now. Bleed RABS. Nope, no change. SO. Do I have the rear brake shoes mis-adjusted? Or is something else going on? I do plan to replace the right wheel cylinder, but I do not expect that to change anything. HELP!