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Discussion Starter #1
Hey all! Been a long time since I was last on. My car has been making some intermittent noises lately, it can occur when braking, sometimes while driving and even in reverse at times. It doesn't sound "grindy" either. More like a vibrating noise. My brake light will sometimes flash on/off, but very rarely, and I'm not sure if its related at all. I haven't noticed any issues in braking performance, but I cant even tell if its my front disks or my rear drums that's making the sound either, its hard to pin down where its coming from. Bad pads wouldn't make noise in drive or reverse, right? So wouldn't have to be the disks?

---------- Post added at 09:31 AM ---------- Previous post was at 09:27 AM ----------

I forgot to mention that there are days where it wouldn't make any sound at all. Also, my brake fluid is full, and a little dirty.
 

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Are your front brake pads worn to the screamer maybe?
 

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Discussion Starter #3
That is a good point, those pads are the same since I first got the car. About time for new ones, heck maybe I should just replace both pads and disks to be safe.
 

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I would, if you are going to do it yourself you may want to by a brake kit too, it includes new slider pins, boots and stainless pad seats.
 

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It's a good video, but with a few flaws, you should remove the old grease on the slide pins and clean the hole where they go into then add new grease. You should also grease the seats where the pads sit which he never did.
 

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Discussion Starter #8
So I basically rebuilt the front brakes. New pads and rotors, plus fresh lube. Smooth as butter, BUT as it turns out, it's the rear drums that are screaming. I intend to redo those pretty soon. New hardware, shoes and drums.
 

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Might just need cleaning on those rear drums.
Normal usage would be 2 or 3 front rebuilds to 1 read drum rebuild.
Note your break fluid level, pull rear drums to look for wheel cylinder leaks, measure shoe thickness, if shoes are good,
Clean and reinstall. Dont forget E-brake cable.
Noise on drum could very easily be casued from a little bit of DOT-3 from a $12 wheel cylinder and brake dust.
 

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Discussion Starter #13
So I pinpointed the noise to the passenger rear drum. I can hear it slide and grind a bit just from turning it by hand. Thing is, the damn thing won't come off. I tried hosing it with wd40 rust release, banged on it with anything from a mallet to an 8lb sledge. Won't budge!
 

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How many miles on your cobalt?
i found if you try to rock the drum by alternating sharp blows at 180 degrees you might be able to free it up.
Top, bottom, top, bottom, left, right, top, bottom......
I use a 2-3lb dead blow This will work if there in no under cut ridge on the drums surface.

Otherwise find the manual adjust plug and loosen the brake shoes auto adjuster with a brake spoon or flat screw driver.
 

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Discussion Starter #15
Just under 74k for miles. I tried looking for that adjuster but it's hard to see through the suspension, and more so to get a screwdriver in there.
 

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How many miles on your cobalt?
i found if you try to rock the drum by alternating sharp blows at 180 degrees you might be able to free it up.
Top, bottom, top, bottom, left, right, top, bottom......
I use a 2-3lb dead blow This will work if there in no under cut ridge on the drums surface.

Otherwise find the manual adjust plug and loosen the brake shoes auto adjuster with a brake spoon or flat screw driver.
Yeah, I beat the ever living shit out of mine to get them off. I actually cracked one of the drums trying to pry the damn thing off. Heavy hammer eventually did the trick. I also think I was an idiot and had the e-brake on. Whoops.

Now, the Cav, I did not make that same mistake - and after three days of deadblow hammers, air hammers, crowbars, PB blaster and swearing, I bought a drum puller and it came off in about 5 seconds. That thing is an amazing tool, so worth the money, even though I've only used it on the two Cav drums.
 

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Discussion Starter #18
So good news. Both rear brakes appear to be working just fine. Ironically, I believe I cured the noise when I was beating the hell out of that drum. I sear I saw something move in that pile of crap that fell out!

Couple things to note though, driver rear drum spins but has a rough spot where it takes some effort to move. The passenger rear drum spins freely but has an audible dragging sound. Overall, from what I could peek at while trying to remove the drums, everything still looks good.
 

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The audible dragging sound is probably just the shoes in contact with the drum.
 
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