Right RearBrake Dragging - 67 GTX

[67GTX440]

Have a problem with right rear brake dragging. Smell of hot brake after a long drive and right rear wheel much hotter to touch than the other three Replaced wheel cylinders that were not moving easily and slightly leaking, and adjusted brakes. No improvement. Turned drums. No improvement. Lubed the back plate to make sure side of brake shoes moved easily against it. No improvement. Springs and brake shoes are correctly installed, look okay and are less than 3 years old with less than 1,000 miles total. Adjust the brakes to where drums slip on pretty easily over brake shoes and still have the problem.

Any other suggestions? The parking brake seems to release okay.

Thanks!

Don Peterson

 

[mlite22837]

Don
Suggest jacking up the rear axle and see if that wheel spins freely after a drive. If it stuck on first open the bleeder on that wheel cylinder and see if the brake releases. This will isolate if the problem is hydraulic or mechanical.

 

[AR67GTX]

If the rear rubber brake line to the axle is old and breaking down inside it will sometimes prevent release of brake pressure as the inner lining collapses. This happened to me. However, that will normally affect both rear drums and keep them locked up instead of just one. Might check that the forward end of the parking brake cables are still secured in proper position in the bracket on the right side underneath.

 

[67GTX440]

After replacing brake lines, bleeding the system, turning drums, replacing brake spring hardware, swapping right and left drums etc, I completely disconnected the left parking brake cable as my next step in the trial and error solution and this solved the dragging/brake heating issue. The cable on the right rear appears to not have been releasing 100%. It was releasing, and appeared to be releasing as far as the left side does, but the parking brake was apparently causing the shoe to drag slightly on the drum. The main cable was adjusted just as far as necessary to turn the parking brake light off when releasing the parking brake. I suspect the parking brake cable was moving inside the cover, but still binding up somewhat. I guess 49 years of use will do that!

I told my wife I am like Tom Edison when I go about working on these things. He tried 1,000 ways to make a light bulb before he found one that worked. He felt like he never failed, he just discovered 1,000 ways not to make a light bulb.

If they ever reopen a plant to build 67 Plymouths, I will be ready for duty!

Thanks for all the suggestions!