red hot rear wheel ..one side?

[Mgicm]

Very odd issue. Replaced master, brake booster, wheel cylinders on rear drums of a 73 3/4 ton GMC. When driving now several things happen. One is it feels like an egg you are rolling on. almost like a bent wheel or brake is grabbing. Front pads were redone and rotors machined. I cant tell if its front or rears that seem to be grabbing. So if I drive it about 10-20 miles, the rear right wheel gets red hot to the touch. rear left wheel is slightly warm. Smells like a burning smell from this one wheel a bit.

Adjusted rear brakes like 4x ..in..out...no change. rear drums are supposedly new.

I dont know where to go from here. Could it actually be something with the rear itself? An odd thing we noticed prior to adjustments - we pulled off rear wheels with truck jacked up in rear. put truck in drive. wheels spun..but right one stopped for no reason and then started again. left side wheel constantly spun. Never saw anything like it. Almost like something was telling it to stop.

Only other possibililty we thought of was the booster we put in was not an exact match of the original as far as the plunger. So it was modified a bit. Not sure if that could cause this.

sure appreciate any direction on this.

[Jstock85]

You definitely have a brake shoe or drum grabbing and staying stuck. I wouldn't drive until you fixed that red hot side. Probably better be safe than sorry and replace the internals on that wheel..

[Mr.Chevy4x4]

You didn't say anything about replacing the shoes. Are they new or did you reuse what was there? Brake shoes that have been soaked with brake fluid or gear oil will tend to grab and cause issues similar to what you are describing.

Mike

[Jstock85]

That may also expose your problem.

[Mgicm]

HI
Sorry ..more info. Note that this work is being done by two shops now..not myself but Im trying to get into the wheels myself at times to see for myself.

We did replace the shoes on both sides. One odd thing noticed was that on the right (passenger) side, one shoe seemed much thinner than another. I didnt get a chance to check other side. I thought out of the box they were both same thickness?? Also changed on both sides was the wheel cylinder. Another issue there was that shop could not locate the proper angled wheel cylinder. Seems the one on the truck had the nipple for the brake line on an angle whereas the replacement came out straight. i believe the first shop had to bend the line. I had second shop check and sees no issues with the work done on the internals but obviously something is wrong.

At this point, im up for replacing anything but dont want to throw money away. What would be a good plan at this time...? to just redo all the parts on the red hot side like wheel cylinders, shoes, etc? What woudl make that right side stop and start for no good reason while on the jackstands? What causes a wheel to stick if it is not something with the rear itself and woudl tell the one brake to engage and disengage for no reason. Totally puzzled!

thanks!

[Jstock85]

Yeah I would start from scratch if it were me.

[Mgicm]

meaning to focus on that right side.. replace everything inside like shoes, wheel cylinder, etc?

Any chance the brake booster could be the cause as it was modified to make it work? I can say before any of this replacement work I never had any issues like this so something that was changed introduced this issue.

[Jstock85]

It sounds like one of your replacement parts didn't fit. or the wrong part was packaged or maybe an error while installing. Once you start taking everything apart you should see obvious sign of wear and that'll show you what you need to do.

[geezer#99]

Check the 'runout' on your hub.
Could be a slightly bent axle or axle flange.

[Nick_R_23]

It sounds to me like you may have a plugged brake line on one side. When you hit the brakes, it'll force fluid through, but the blockage may be bad enough where it doesn't allow the pressure to release quickly, and keep the wheel cylinder engaged. A 1973 truck is probably due for new lines anyway.

[Jstock85]

Good idea nick! Disconnect your lines at the prop valve and use compressed air. If thats all it is then you caught a break!!

[Dead Parrot]

Focus on the right rear. The shoe is thinner because it is dragging all the time, causing the heat. Drag = wear = heat. The stopping while the wheels were off the ground was due to the drag.

It is possible to reverse the shoes on a drum brake system. Download a good picture of a Chevy drum setup and compare to yours.

A bad booster should affect all the brakes. A bad master cylinder should affect more then one wheel.

Suspect the prop valve, plugged line, bad wheel brake cylinder or incorrectly installed shoes and/or springs on right rear.

[hewittca]

I had a similar problem but not quite as severe. I thought, I'll do a full brake job and everything will be right again. I replaced drums, shoes, wheel cylinders, and all springs, but my left rear would not bleed properly. I decided it was time to do all new brake lines and now the brakes work perfectly.

[Honest Bob]

I had a collapsed brake line lock up one of my front calipers, I imagine the same thing could happen in the rear.

[kwmech]

The shop could have gotten the wheel bearings too tight also. AND if they got the angled wheel cylinders they may be the wrong inside diameter. You have 11'' or 13'' drums? They could have also reversed the shoes on 1 side, which would cause weird problems when engaging.

[asphaltburner]

Old rubber flex lines can swell and obstruct brake fluid return. Pressure will build in the line, but not relieve. I have had to solve this problem before. It's a cheap fix.
Best of luck!
Todd.

[raceman6135]

I've had the parking brake (aka emergency brake) cable begin to seize on one rear wheel, which would then drag the shoes on that side, causing one hot drum/wheel and excessively worn shoes.

I agree with others who have said the issue could be anything at this point. Time for more investigation.

[RedBed]

My front brakes did the same thing. Replaced the lines on both sides and was good as new.

[truckin 79]

All good advice here I would also throw in that maybe the wheel cylinders are the problem. I dont know why other shop could not locate the correct ones but there is a reason your truck had those wheel cylinders. I bet the new cylinders are pushing the shoes out to much where the old ones probably collapsed down further in the wheel cylinder. I would look up on online your self and try and find correct wheel cylinders for your truck. I recently replaced shoes, drums and wheel cylinders. The parts store only listed on set of WC but turns out there are 2 different ones for a 79 heavy half. Good Luck

[riz]

Inspect your brake lines.... if they are old or stretched they can actually collapse on themselves and cut off the flow of brake fluid...... ask me how I know.

[Jstock85]

Whats the verdict?? This issue ever get resolved?