I have a 1982 Toyota 1 ton RV, here is the problem, The front brakes lock up (Both sides) once the fluid heats up. Regardless of what is done. Here are the things that I have done : New front Brake Calipers (both sides), replaced rear wheel Calendars, Replaced front pads, replaced master cyl ( 3-4) times- not new, but rebuilt, changed fluid 2-3 times, checked brake pedal adjustment, dismantled and cleaned the proportioning valve. The brakes do work fine until fluid warms up. Once the fluid warms up, the front brakes lock and will release if I crack loose the front line at the master and if I crack loose the rear line at the proportioning valve (in effect, that's cracking it at the rear of the master). Also replaced two front rubber brake lines at the calipers. Every thing is new except for the proportioning valve (thought I'd mention that I cannot buy new, let alone even find), and the rear drum brake shoes (witch are adjusted and in good shape. What the hell is up?? If your info fixes it, I'll donate more.
have the same problem?
Monday, December 10th, 2012 AT 5:33 PM