Parking brake issue

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GMClearner

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1. Good news: You don't have the horrible 254mm (10") leading-trailing shoe rear drums. You almost certainly have the JB/JN 6, 11.x Duo-Servo rear brakes.

2. Looks to me like the adjuster is fully-retracted. Good chance that the service brakes are WAY out of adjustment. Could be that the adjuster is seized or otherwise malfunctioning. The service brakes have to be properly adjusted BEFORE you adjust the park brake. You MUST retract the park brake lever at the drum assembly BEFORE adjusting the service brakes--the shoes MUST BOTH TOUCH THE ANCHOR PIN at the top of the brake assembly before the service brakes can be properly adjusted.

3. Why is the interior of the brake wet? Leaking wheel cylinder? Or did you spray lubricant on the exposed part of the park brake cable, and get a lot of overspray?

4. When the park brake pedal won't return, it's almost always due to seized cable(s) in the park brake system. I suppose that the park brake pedal assembly could be stiff/seized, but I'm betting that the cables are rusted. You could spend the rest of your life trying to lube them, and maybe you'll have success. When it's me, the seized cables go in the scrapmetal bin, and I install new cables. New aftermarket cables are surprisingly inexpensive; (in part because they're cheap Chinese) but they're not a perfect match to the OEM cables in terms of the mounting brackets and such.

The short story here--that I'm inferring from a single photo of some of one brake assembly--is that your park brake is perpetually applied because the cables are seized. That is forcing the park brake equalizer bar under the wheel cylinder to spread the shoes apart. And THAT is preventing the service brakes from properly adjusting. THAT is MAYBE causing a wheel cylinder to over-extend and leak. It's also why the park brake pedal can be pressed, and not stop the truck--the park brake is always applied, but the service brake adjuster is so loose that the shoes don't put pressure on the drum.

Given the non-rusted condition of the brake shoes, and the very thick lining material, I'd say the last guy to service the brakes had no idea what he was doing.
Well i was the one to spray some deep creep on it to see if it would loosen, as for the brakes themselves i changed them out as they were not working at all due to cylinder failure and previous owner disconnected the brakes completely, the adjuster i adjusted to get better braking in the rear , the parking brake ive never dealt with and im also looking at replacing the whole cable .
 

GMClearner

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Well i was the one to spray some deep creep on it to see if it would loosen, as for the brakes themselves i changed them out as they were not working at all due to cylinder failure and previous owner disconnected the brakes completely, the adjuster i adjusted to get better braking in the rear , the parking brake ive never dealt with and im also looking at replacing the whole cable .
Also ive noticed the park brake cable is only loose and hanging when the pedal isnt pressed down, is it possible with the rusty brake cable that they stretched out?
 

GoToGuy

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It gets loose because it's not moving within the cable housing. It's as if the rust and corrosion has glued the cable in place.
Unless you can remove, disassemble, strip corrosion, it often easier and more effective to replace the rusted parts. Like brake cables.
As it stands the adjustments are so out of whack, you best choice is new cables properly adjusted, and shoes adjusted correctly.
Lube, penetrate products are the enemy of brake shoe, linings, use caution. A product called " Sylglide "; small dab, can be applied to the six wear pad areas on the backing plate.
This to add to Mr. Schurkey 's advice, not take anything away
Take a little extra time and it will be more effective and have a long service life.
 

GMClearner

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It gets loose because it's not moving within the cable housing. It's as if the rust and corrosion has glued the cable in place.
Unless you can remove, disassemble, strip corrosion, it often easier and more effective to replace the rusted parts. Like brake cables.
As it stands the adjustments are so out of whack, you best choice is new cables properly adjusted, and shoes adjusted correctly.
Lube, penetrate products are the enemy of brake shoe, linings, use caution. A product called " Sylglide "; small dab, can be applied to the six wear pad areas on the backing plate.
This to add to Mr. Schurkey 's advice, not take anything away
Take a little extra time and it will be more effective and have a long service life.
Ya it wouldnt surprise me even they were never used at all since the previous owner didnt even use the rear brakes at all, was even missing springs when i opened it up, so i ordered all brand new , so gonna replace the cable to while i am at it, rather be safe then sorry for not having it
 

GMClearner

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It gets loose because it's not moving within the cable housing. It's as if the rust and corrosion has glued the cable in place.
Unless you can remove, disassemble, strip corrosion, it often easier and more effective to replace the rusted parts. Like brake cables.
As it stands the adjustments are so out of whack, you best choice is new cables properly adjusted, and shoes adjusted correctly.
Lube, penetrate products are the enemy of brake shoe, linings, use caution. A product called " Sylglide "; small dab, can be applied to the six wear pad areas on the backing plate.
This to add to Mr. Schurkey 's advice, not take anything away
Take a little extra time and it will be more effective and have a long service life.
Quick question since im trying to keep this all in one thread to avoid negativity lol , u say the shoes arent properly adjusted can u put some light on that subject or should I take a bigger picture and post it first? Was my first time doing these ,would appreciate the assist
 

Schurkey

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u say the shoes arent properly adjusted can u put some light on that subject or should I take a bigger picture and post it first?
Take SEVERAL photos, and post them.
1. The entire brake assembly
2. Close-up of the shoes where they should touch the anchor pin at the top.
3. Close-up of the bottom of the shoes where the adjuster arm touches the star-wheel, and showing how many threads of the adjuster are showing.
4. The braking surface of the inside of the drum--showing gouges, scoring, heat-checks, etc.
5. Repeat for the other rear brake

In-focus, nicely-cropped, please.
 

GMClearner

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Take SEVERAL photos, and post them.
1. The entire brake assembly
2. Close-up of the shoes where they should touch the anchor pin at the top.
3. Close-up of the bottom of the shoes where the adjuster arm touches the star-wheel, and showing how many threads of the adjuster are showing.
4. The braking surface of the inside of the drum--showing gouges, scoring, heat-checks, etc.
5. Repeat for the other rear brake

In-focus, nicely-cropped, please.
Passenger side
 

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Schurkey

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20241007_180750-jpg.388863

Is the secondary shoe touching the anchor pin? Seems like it may not be. Is there a gap between the forked, forward end of the park-brake spreader-bar (the end with the rectangular spring) and the primary shoe? There should be a small gap there.

20241007_180801-jpg.388866

I can't tell for sure if the park brake lever is being pulled upward, but if it is, that probably accounts for the shoes not touching the anchor pin.

20241007_180811-jpg.388867

Adjuster lever is not touching star-wheel, to prevent it from turning. Adjuster that star wheel is attached to looks like it maybe needs to be popped "upward" and properly seated into the Primary shoe.
I have the sense that the coil spring on the park brake cable is overly-compressed--coils too close together--as if the park brake cable has been pulled too tight. That could be the root cause of the shoes not touching the anchor pin, and the spreader-bar holding the shoes apart.

I don't see photos of the inside of the drum, to check for scoring.
 
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Schurkey

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Teeth on the star-wheel worn off, or optical illusion? If the teeth really are worn, you need a new adjuster. The teeth wear off when the adjuster seizes, and the adjuster lever attempts to turn the star wheel, but can't. Make sure the adjuster lever isn't similarly worn.
Again, looks like maybe the forward end of the adjuster needs to be popped "upward" with a hammer so it seats into the shoe properly.
Again, the coils on the park brake cable seem compressed. MAYBE that's an optical illusion, but if the spring on that cable is compressed, that'd account for the shoes not touching the anchor pin, and the spreader-bar holding the shoes apart.

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White spring at anchor pin overlaps bare-metal wire for brake adjuster.
Looks like rectangular spring on park-brake spreader-bar is collapsed. Probably means park brake lever is being pulled by the brake cable.
Again, I don't have a clear view of the shoes touching the anchor pin. Maybe they are...maybe not.
And also no photo of the inside of the drum.
 
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