'86 Bronco brake prob - continued

Well, the vibration/lock-up problem still exists. Yesterday the following was replaced:
wheel cylinder brake line (just within, not the entire line from the master cylinder)
shoes/springs
One thing I did find out is that the right axle has a repair bearing. I'm not sure if this is of any significance since I notice no vibration at any speed. Something else to note: the wheel that is locking up is at least 40 degrees hotter than the driver's side/rear wheel (this was acutally measured btw). It's not clear if this is just due to the brake problem or a (possible) bearing problem (i.e. is the heat the result or the cause).
At this point I can only come up with three wild guesses:
1) The repair bearing is bad in some way, causing friction, and therefore a heat build-up. Eventually the brake starts to have a problem.
2) The pressure is still building up in the right/rear brake, causing a heat build-up and eventually the lock-up problem.
3) Both #1 and #2 where one problem is making the other problem more acute.
As always, theories are welcome...
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How old are the linings and what kind? The bearing will not cause the brake to lock up even if it is bad. What has been done before the brake lock up problem started?

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i only had this happen once - it was on a 1957 ford. right rear wheel also.
the wheel bearing went bad, allowed the brakes to drop onto the drum and heat it up. it my case, it got so hot the tire couldn't hold air and went flat, the heat took out the grease seal and when the tire went flat, the oil from the rear end ran out onto the hot rim and caught fire. luckily, the driver behind me was a vol. fireman and had a fire extinguisher with him and knock down the fire in nothing flat.
strange things do happen. but i don't know if that is the same in your case.
hope this helps.
~ curtis
knowledge is power - growing old is mandatory - growing wise is optional
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Not too start an argument, but the chain of events are not quite what you are thinking.

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====================Try this, while coasting at about 10mph, slowly apply the park brake to see if it locks up that way. Try it a few times. If it does that will eliminate a strange problem with the master cyl or proportioning valve. Check the backing plate for grooves that are worn from the shoes rubbing on them over the years. Usually this will happen toward the top and bottom. If there are grooves they can be brazed or welded up then ground down smooth. You really should turn or replace the drums also if it wasnt done, if it has hot spots or is out of round that sure wont help :). Oh, and before you yank the shoes off make sure that if the friction material is different sizes(one shoes friction longer than the other) the long one goes on the rear. GL
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