Brake Issue, Passenger Rear Brake Frozen on Take-off

[lts70]

On my 70 Chevy I have noticed that the rear passenger tire/wheel is locked up when I first get going in the morning. It feels like the rear parking brake is on for that side. It only lasts on my initial take off then goes away. After the truck has sat over night or when I get done with work it happens again. Once I get going and even come to a complete stop again it does not happen again and acks completely normal on take-off until the truck has sat parked for awhile. It does not occur when I go in reverse only when I go forward. I can back out of my drive way just fine and then when I go to go forward it takes more gas to overcome the friction and I can feel the bind until I get moving. On gravel it will even drag a bit before it breaks free. It has happened for the last few days each day getting a little more aggressive. I am going to pull this apart tonight and take a look. I was wondering if anyone has any suggestions of what to look for. I am thinking it must be a bad self adjuster or parking brake issue but have never had this happen before so input would be greatly appreciated. I have only had to drive it a half a mile a day as I meet a co worker at a park-an-ride to commute for work, so I hope I have not caused too much damage if something is mangled in there. Next week I have to start driving her 60 miles round trip again so I defiantly need to get this fixed.

[k.t.]

Oil or brake fluid can make that happen. Check to see if your leeking anything at that wheel, bad slave cylinder or axel seal.

[68gmsee]

Has it always done this? Any work done on the rear brakes, like adjusting?

I agree that grabby brakes will give this symptom. Drum brakes are designed to expand slightly when they make contact with the drums. Sort of like a drum assist. If the brake shoe is grabby and it's making slight contact with the drum, it may be just enought to cause it to do that.

A collapsed brake hose keeps the brakes from releasing and basically cause problems when you use them so your symptoms don't seem to indicate that. But, it's still something to consider. Not all failures give the same symptom all the time.

If you wanted to really find out if it's the rear end or the brakes, you could disconnect and plug that rear brake line then loosen the rear brake shoe.
Most of the braking action is done with the front wheels so if you're careful you could test it this way,

[lts70]

Well I finally got time to get my garage cleaned out and my back wheel and drum pulled off. The brakes and drum are in good condition with no groves or uneven wear and have no oil or anything on their surfaces. The axle seal seems to be leaking a bit and the adjuster is greasy but moves freely. I was easily able to back off all the pressure that was locking the wheel up and the drum came right off. All of the springs seem in good order. Does anyone have any ideas of what the heck is going on?

[cdowns]

rusty backing plates can cause bad cyl too //take off the drum and do some brake maintence usually fixes it

[lts70]

Well I pulled things apart again for the third time last week and saw nothing wrong for a second time. I went ahead and cleaned everything up good and put a new spring kit in and beveled the edge on the brake pad. It seemed to be better for awhile but after her first long drive I parked her and in the morning she was locked up more than before. Now the lockup doesn’t seem to release and that same passenger side gets very hot in a hurry. I am going to take her apart again tonight to see if I am missing something. This is driving me crazy, when I open it up nothing seems to be wrong. The adjusted moves freely, as well as the cylinder.

Is there something that could be causing it to over adjust?????? Any ideas would be appreciated!

[mrein3]

Have you bled the system recently? Old, wet, contaminated fluid could be freezing in there - being that you are in Utah that is a possibility.

I would get all new fluid moving around the system and see if that fixes the problem. Use a turkey baster or similar and empty your master down to just above the ports that feed the brake lines. Fill it back up with new fluid. Then go from wheel to wheel until you get clear, new brake fluid out at the bleeder. Of course don't let the master go below the output ports or else you'll need to bleed the master.