I'm having a strange problem with my 1986 Bronco XLT, where the right (passenger) rear drum has started locking up after heavy use. This only happens if I've been driving in heavy traffic (stop/go, you know the drill) for about half an hour. Basically:
- Initially driving: no problem...no lock-up, no vibration, acts fine
- Drive in stop/go traffic for roughly thirty minutes: the right rear wheel will lock at any speed, not much pressure is required on the brake. There's also a vibration after this starts happening (i.e. if there isn't a lock-up, I get a vibration when braking).
I've never had this problem before...actually, my drum brakes always got worse when heated up so this is REALLY a new one on me. So far I've replaced the master cylinder, brake shoes, and rear drums (driver and passenger). No change. Just to be clear: this only happens with the right rear wheel.
Anyone ever experience a similar problem, or have thoughts on a solution? At this point I can only see replacing the guts of that right rear brake.