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Discussion Starter · #1 ·
I've never dealt with drum brakes before last weekend, so this may seem like a no brainer of a question but here goes:

With improperly functioning parking brake cables on my '96 C1500 5sp, are the rear brakes still going to function properly when driving the truck?

I just replaced all the rear drum/shoes/hardware/adjusters and I have come to realize that the adjusters are set by use of the parking brake if I'm not mistaken. With never using it (always park in gear, never on hills) will the rear brakes still self adjust and give continued proper service?

I have the 10" brakes on my truck and the backing plates don't really look like they have a practical adjuster hole in them for servicing the brakes without removing them. So if the general idea is that I NEED THE PARKING BRAKE CABLES TO ALL FUNCTION PROPERLY FOR THE BRAKES TO STAY WELL ADJUSTED, then I will spend the money and take it all back apart and do it right.

Ideas? Info?

Thanks!
 

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Discussion Starter · #2 ·
Also worth noting - w/ all the new parts on the truck I took it for a test drive around the block and WOW it actually stops somewhat safely now. I'm very pleased w/ that because I was downshifting my @$$ off before just to slow her down. The rear drum assemblies were completely shot, missing parts, broken parts, rusted parts, etc.

Now everything is new except the cables, backing plates, and wheel cylinders.
 

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Sounds like you did everything right, the key is (aside from assembling the springs correctly and making sure the actuator arm that the cable pulls on is free and lubed with brake grease) is the star adjuster nut.

Got to have the whole axle up and in neutral. You can also do this with the wheels on and sitting on the ground. There's always a small opening on the lower inside of the drum backing plate- should have a rubber grommet in it. Pull it off, use a flat head screw driver to flick the star nut up or down to push the shoes in or out. You you to adjust until the shoes make full contact to the the drum, then back off a few flicks.

The parking brake should fully hold the truck on a incline at about 3 clicks of the parking brake lever.

The adjuster nut SHOULD automatically adjust out with normal brake use, but brake dust and dirt will stop that from happening.

When doing the drums, I make sure everything is very clean and lube any contact points with brake grease.

Also worth mentioning, some vehicles have a separate smaller drum ('in-hat') for the e-brake, even if it's a disc brake. Same adjustments apply.

When done, drive and make sure the wheel is not getting real hot, that means the shoes are dragging or too tight.
 

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Discussion Starter · #5 ·
Thanks for the reply and info.

Just to clarify though, because I'm still not sure I got the answer I was looking for -

My parking brake/e-brake does not work at all, cables are junk. Will my drum brakes stay within proper adjustment even though I never use the parking brake?

I set the adjusters all the way in to get the new drums to fit over the new shoes... and though I did find an access port on the backing plate, it was tiny and I didn't bother trying to adjust as I could hear a slight drag when rotating the tires, though I did it in gear, the tires would rotate pretty easily with faint audible dragging noise heard. I could get them spinning 8-10 revolutions upon initial setup. I have not jacked the truck up since then to see if the adjusters moved any and tightened up the brakes. I will have to do that tonight and see what's going on.
 

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Yes, your rear brakes will function fine without the e-brake cable- although I'd get around to replace the cable soon. Brake pedal hydraulically-actuates and your e-brake is cable-actuated. Brake pedal pushes the wheel cylinder to push the shoes out, e-brake pulls the actuator arm to move the shoes out mechanically. Reason being that brakes all now need the engine vacuum for the brake booster, so when engine is off, you still may need to use the e-brake...

The adjuster nut- good, you found it. And yes, that's typically the way to get the drums back over the shoes (to back off the adjuster nut all the way back). Definitely adjust it back out to where it makes the shoes contact the drum (after drum is back on), then back it off a few flicks. You may be dragging it and that's why your brakes feel like they're working so good... I like to do it with the wheels on because it clamps down the drum onto the hub keeping it as square as it it'll get.

The adjuster nut, if clean, SHOULD seld-adjust with normal brake use- you may hear a few clicks happen within a day or two after doing a full drum brake overhaul.

Make really sure all the shoe contact surfaces and the adjuster nut are very clean, then re-lube. If there's any sign of oil on the backing plate (and its not coming from the axle hub), that would indicate a leak in the wheel cylinder that will make the brakes less effective and obviously eventually fail and blow out brake fluid.

Also make sure that actuator arm for the e-brake is not frozen and moves easily. That locks up and your whole deal is screwed. I see this frequently on trucks that spend time in the mud, the tell is a very hot wheel and a brake smell after you park after going for drive. A quick fix is to simply wack the actuator arm back with a hammer and then not touch the e-brake lever until it can be rebuilt.
 

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Discussion Starter · #7 ·
I appreciate your helpful info and advice.

I'm just trying to understand a drum brake more thoroughly and I don't think I'm getting the concept of them staying in spec w/o the e-brake being used to periodically expand the self adjuster. Unless you're advising me to do it manually every so ofter.

I get the brakes are hydraulic and the e-brake is cable. What I'm trying to figure out is say, in 20k miles of no e-brake use, won't the self adjusters still be all the way in/loose and at athat point the shoes worn and the brakes possibly less functional?

It's the self adjuster that's screwin with my simple mind. lol
 

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Discussion Starter · #8 ·
Oh, and the self adjusters are new on each side as well, so everything is clean and I lubricated the self adjuster assemblies with antiseize, but used brake lube on other points (backing plate, brake shoe contact points - no shoe surface).

The only original parts is the backing plate, wheel cylinders (they were dry under the boots), and the e-brake actuator arms.
 

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They SHOULD self-adjust- in fact if you had the wheel and drum off, the adjuster nut all the way back down, then pumped the brakes, you'd see it (hopefully) clicking past the spring and adjusting the shoes out further (because there's not drum stopping them). Its just good to get it very close to start when you do a rebuild, saves that amount of time to get them to self-adjust. When you flick the adjuster nut through the hole in the backing plate, you'll hear the star nut clicking past the spring right next to it.
 

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Discussion Starter · #10 ·
Thanks CT2500HD. You've obviously been there/done that. It was my 2nd drum job, my first being 1 day prior!

I think all is well, thanks for all the help.

I'm driving it on the interstate in 3 hours about a 60 mile round trip to load up some 55gal drums and take them to my parents house. Guess we'll see how she performs today since last night I only put about 10 miles on the new brakes.
 
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