I'm at a loss..

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PrairieDrifter

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Too much to reply to. I'll put $1000 dollars down that says i can block off the rear axle from brake fluid, and it'll still drag. I'm done throwing money at the stock brakes. I've heard nothing but terrible reviews from new proportioning valves. I am aware how a proportioning(combination) valve works. I did A LOT of research before I ever thought of making this thread. I've actually been fighting this since last year, my truck was broke down from other reasons for a while.

I SHOULD NOT be able to adjust the shoes far enough off that I lose brake pedal feel, and still have drag. Not just drag but drag that produces the SAME heat as properly adjusted with basically no brake input. And not to mention heating up one side 10x faster than the other, on a system that shares the same hose and feed pressure. As well as in less than five miles I can feel the drums and they're already getting hot.

Also I can't feel this drag at all till they get really hot, and it's not dragging hard guys. It's just dragging enough for me to barely feel it and the brakes start squeaking constantly even when not being used. Because the shoes and drums are expanding when you sit at a light or whatever and there's no cooling happening.

It's not intermittent, it's not irregular its not pulsating. It is consistent and constant and even(not side to side). Two masters, all the replaced rear brake components multiple times now, but was fine before the rear drums, shoes and hardware, no dragging brakes. There is no residual pressure after brake use, and the brakes operate properly during braking operation.

Ive had three drums on it now, 4 actually, because two old ones were from different axles. FOUR different drums of different wear. 2 old, uncut. 2 new, 1 of those new ones was cut. I am running one new cut drum and one old drum. The old drum is the hot one... The brakes DO NOT lock up at any point or ever have. They operate properly.

Also not to be a dick. But this would be a lot more informative, non cluttered thread if some of you could take the time to read the whole thread. I'm already frustrated and confused enough with the issue, I don't need to be doubling back on things that have already been mentioned(since apparently this thread is too long already) what's the point in having pages organized with comments, just to ask the same questions? Might as well get on some instant chat site.

I apologize for the "outburst" but the doubling back is just counterproductive and frustrating. On top of my already present shitstorm lol

Also just a random observation, if a "mechanic" doesn't know to look at a rubber brake hose for brakes locking up, and it's a head scratcher, there's something wrong there. Just saying.

That being said I appreciate ALL of the input and comments. Nothing personal!
 
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bucket

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It's odd they can build up so much heat, but not have noticeable drag. So I'm assuming that when you have had the drums off, the shoes appear to be wearing evenly?
 

PrairieDrifter

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It's odd they can build up so much heat, but not have noticeable drag. So I'm assuming that when you have had the drums off, the shoes appear to be wearing evenly?
I haven't felt "normal" in this truck for over a year now so I can't say I am gaining exactly x amount of rpms, but from cold to drums getting hot I'm jumping about 200ish rpm after a long trip or driving multiple places. But I know it's different from before the brakes. Im super convinced it's mechanical.

These pics were from last year and the last set of new brakes. This was one of the new drums uncut. You can obviously see the outsides are hot and the center is not. Can't really tell on the shoes, kind looks like it's just wearing in the center of the shoe. This is why I had the drums cut, it almost looked dished to the eye even.

Im so over it, I've just been driving it without looking at them yet. I haven't had them off. But I bet they look similar.
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andybflo

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Also just a random observation, if a "mechanic" doesn't know to look at a rubber brake hose for brakes locking up, and it's a head scratcher, there's something wrong there. Just saying.



None of us are mechanics by trade; but he's owned, restored, kept (and sold) more cars than you can count. Including at least a dozen Squares and K5s. He's a lineman, I'm a corporate finance director for a Fortune 20. Can't pay the bills (sadly) turning wrenches. First time you see something is a first for everyone, isn't it?

So, if you have four drums, new hardware, visibly new WCs, multiple sets of new shoes, new parking brake hardware (or checked that it's released), turned drums to make sure they're true... That adjuster is pretty far out in that image for new parts (my JB5s are maybe a thread/thread and a half, and I've got 3k on the brakes. Had them off to inspect, post-winter storage.) What mechanical parts are left? I'd highly doubt four drums are defective, including ones (I'll assume) that gave you or the previous owner good service in the past.

You have aftermarket axles. Are they straight? Have you pulled them out, put them on a machinst's table? Taken them to a machine shop, had them checked for true? Literally storing axles incorrectly in a parts warehouse can cause them to warp slightly.

Checked the axle bearings? I own a '63 Impala that did something similar (it's an old GM-Eaton center section rear end, not a "modern" 10/12 bolt) in the late 90s. Lunched an axle bearing on one side, and scuffed as it was out of round. at higher/extended speeds, it was more continuous.

Looks like the rear end was apart here. What did you change? Did it work OK before that? Did you use the carb cleaner on the brake shoes pictured above (there's usually lubricant in carb cleaner), causing the shoes to swell?

As I said before, and this isn't a cut. My wife sometimes needs to kick me with this same question; you keep checking/replacing the same things, with the same results. Tear into something else. If you don't think it's hydraulic, think of anything that spins in the back that could be oval, not round.

Re: Aftermarket prop valves; I've never had one leak. I have had one stick. But... Found a good local supplier (Was SSBC, now the engineers left, formed LEED), keep buying from them. I can drive over, have a beer, and get my parts from the factory.
 

MikeB

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I am running one new cut drum and one old drum. The old drum is the hot one...
Does the old drum get the hottest no matter which side it's on? If already asked and answered, well that's what happens with long threads and lots of guys simply trying to help.
 
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JamesSam

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Mason, I really hope you get this figured out. My brakes have squeaked a little ever since I bought my truck and I'm afraid it's getting more prevalent. This thread makes me fear the worst. Good luck.
 

Hunter79764

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An old coworker used to say "If you find yourself beating your head against the wall too long, you might think whether you are beating on the right wall".
I've tried to follow everything here, but I've got a couple questions.

Seems like the problem doesn't follow drums, new, old, cut, not, all have similar behavior. Does it follow left to right? How about your brake shoes, does it follow those? I'd be tempted to get a cheapie pair of shoes just to try to eliminate those. If it's no different, pull them off and return to your least favorite parts store.
Your heat indication on the drums looks like the edges are hotter than the middle. Is it possible your shoes are installed cockeyed and dragging on the side/edge of the drum?
Stupid question, but are you sure the shoes are on correct? We've all been there and put something in backwards or lined up on the wrong hole on accident. Can you pull some drums elsewhere, or have a buddy take an independent look? Got a factory manual with clear pictures?
How many times have you uninstalled/reinstalled the shoes? If you put them back "Exactly like they were before", it's possible you are unintentionally recreating the problem.
Are you sure the return springs are returning correctly? Run it on jack stands, let them warm up, and see if you can pull the drums off while it's still hot. If they slip off alright, your return springs are pulling them back in ok, and I'd be looking at the shoe edges dragging somehow. If you can't pull them off until the drum cools down, you have a problem on the main pad surface like typical dragging. See if heating the drum up externally (and evenly) with a heat gun or something gives you the same behavior.
How's your wheel cylinder? If that has some trash in it, I'd think it can act as a check valve too, although it sounds like you did the bleeder test when they were hot and dragging, and came up dry. Not sure where the bleeder is vs the cylinder, so that might be a possibility somehow, I don't know.

Overall, tough issue. There's a lot of times that "Shouldn't" still "Is", and others where the problem isn't what you don't know, it's what you know that just isn't so. Good luck on figuring out which this is, I don't envy you on this one.
 

PrairieDrifter

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Does the old drum get the hottest no matter which side it's on? If already asked and answered, well that's what happens with long threads and lots of guys simply trying to help.
Again it's not to be a dick. I understand not everyone has the time. I just can't give clear and concise info and replies if I have to read through the whole thread just to reply to one person. If anything is wrong the confusion grows exponentially.

I haven't swapped anything lately, but I bet it won't follow the drums.

Im leaning towards crap shoes. That being said this is the second set of shoes, better than the last but not good.
 

rusted nuts

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Again it's not to be a dick. I understand not everyone has the time. I just can't give clear and concise info and replies if I have to read through the whole thread just to reply to one person. If anything is wrong the confusion grows exponentially.

I haven't swapped anything lately, but I bet it won't follow the drums.

Im leaning towards crap shoes. That being said this is the second set of shoes, better than the last but not good.
Maybe try free quick stuff . stuff 1st
 

rusted nuts

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Mason, I really hope you get this figured out. My brakes have squeaked a little ever since I bought my truck and I'm afraid it's getting more prevalent. This thread makes me fear the worst. Good luck.
Driffent brands of shoes can Squeak more than others also a squeak is just a vibration You can hear.
 

Lowered87

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Quick stuff:
1: prove it is not hydraulic related
2: make sure all of the parts are correct and installed correctly
3: turn the axle and make sure all components turn true and are square
4: increase insurance and have an "accident"
5: go to truck show and leave with "free parts truck"
6: earplugs or louder stereo equipment to drown sqeaking
7: water bath to cool drum while you complete the wear in process
 

PrairieDrifter

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Quick stuff:
1: prove it is not hydraulic related
2: make sure all of the parts are correct and installed correctly
3: turn the axle and make sure all components turn true and are square
4: increase insurance and have an "accident"
5: go to truck show and leave with "free parts truck"
6: earplugs or louder stereo equipment to drown sqeaking
7: water bath to cool drum while you complete the wear in process
I've done all but 4 and 5 lol
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armor2111

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I found out that when it comes to drums, The longer shoe faces forward and the shorter one to the rear. I cannot say for sure so you guys with real tech know how will need to verify.
 

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I know thread is a couple months old,,but I'm assuming the brake shoe hardware was installed correctly? this opposite sides mirror images of each other. It's easy to but a spring on backwards, causing a bind, or the self-adjuster was flipped, or even the bar and related spring installed backwards. I work in a shop and 90% of brake shoe issues are incorrect installation. Just thought I'd throw that out there
 

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Did this vehicle originally have a 10 bolt rear?
 

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