I am leaning toward a hydraulic problem like most are. But let me relate a story in the off chance it is something equally as weird. I had an old chevy truck that would lock one wheel. We put the truck together from several old trucks and I suspected it was mix matched parts. Finally after pulling my hair out I was sitting and tapping my screw driver on things. Off chance that I tapped one of the shoes and it made a thunk. I checked closer and the front lining on that brake that would lock up had loose rivets. I changed the shoes on both sides of the front and everything was fine after that. my guess is that the shoe would loosen up part of the time and when the brake locked it jammed it up tight for a while.
Did you use high speed brake grease on all the pivot points and the springs ends. you could also have a warped or warn backing plate
Had the very same problem on my O/T Dodge stepside truck. Left rear drum would lock up and then release after sitting overnight or longer. But as you drove it, it would function normally. I replace everything, wheel cylinders on both sides, rubber hose from the frame to the rear end, and swapped drums that were practically new. Nothing seemed to help. The shoes looked brand new and dry. As a last resort I bought a new set of shoes and that fixed it, not a problem since. Edit: I read my reply back and need to express that this would happen after the truck sat overnight or longer. The left rear would lock up and release immediately.
I've got the manual for the Lockheed (1) brakes and will bring it over when the new shoes arrive. Setup shows using a feeler guage for proper clearance.
[QUOTE=" A plugged brake line or hose would not get better with use. "After driving and applying brake slowly, it functions correctly." I suspect that you have a leaky wheel cylinder on the left side. Overnight, the shoes get damp on the left side and GRAB when you first apply the brakes. Drive it and drag the brakes a little and they dry out. Sit overnight and here we go again. [/QUOTE] This happened to me as well. Turned out to be weeping cylinder. Very small leak, very hard to spot.
there are two holes in the inside bottom of your master cylinder. one is so fluid may return into the m/c after brakes are released...if the return hole is blocked it will cause the brakes to malfunction, you can check it with a pin or wire.
Had a customer car one time that would lock up the r rear wheel every time you stepped on the brakes. Had the r rear drum off a dozen times trying to figure out the problem. No luck. Finally took off one of the other drums and found out the wheel cylinder was frozen. Pulled the other 2 drums and the wheel cylinders were frozen on those also. Ended up the r rear brake was the only one working.
we have the manual, but bring yers, maybe it is more specific, ours is "kinda general" Hey, why is your kid in las Vegas? Gilbert Police is hiring, "nice area" safe, no daily killings, and beautiful newer progressive, city.
all brand new wheel cylinders,hoses, we watch when drum off, functions correctly. New brake shoes ordered.. .. waiting.
I had the same issue on my plymouth but on the driver rear. Had the shoes relined and that took care of it. Pads never looked like they got fluid on them.