# Pop noise, drives like in low gear, burning smell rear tire - 95 Chevy c1500



## tireshark (Aug 17, 2014)

Was driving today about 40 mph and heard what sounded like a muffled pop or something, and the truck immediately started driving funny like it was under a heavy load, or in a lower gear. I thought a tire had popped, but when i got out to look nothing was wrong with the tires. Drove it home and it continued to feel like it was in a lower gear or something. In the driveway it seemed like there was a burning rubber smell coming from the passenger side rear tire.


Also, for the past month or so, the ABS light has been coming on sporadically.
Ideas? Something to do with the brake, or maybe the parking brake? 



Pretty sure the rear brakes are drum brakes. Have replaced calipers and brake lines on the front brakes, but never messed with the rear ones before.


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## DexterII (Jul 14, 2010)

My guess would be that they are drums, but you should be able to tell by looking through the webs in the wheels, or may have to look in from underneath if solid steel wheels. With the front tires blocked, raise the rear tires, and you should be able to turn them by hand.


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## jimn (Nov 13, 2010)

ABS light indicates a problem . I had 1999 Pontiac car that had ABS issues which would essentially cause the rear brakes to never full release and eventually lock up. Early symptoms where similar to yours The solutions was replacing the ABS actuator ($$$$) and both rear brake assemblies.


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## Brainbucket (Mar 30, 2015)

Need to remove the rear drums on both sides to inspect the brakes. More than likely there is damage there. Make sure the oil seal is good. If not, replace the bearing also.:vs_coffee:


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## tireshark (Aug 17, 2014)

Thanks for the input everyone, i had a leg injury the past few weeks and am just now getting able to work on this.

I jacked each side up, one at a time to see if the wheels would spin.

With the vehicle in neutral:

Driver side rear wheel spins by hand.

Passenger side rear wheel will NOT spin by hand.

The vehicle will drive, but it feels like there is a large load or something. So the tire will spin under acceleration, but i could not spin it by hand.

Also wanted to re-state that the ABS light had intermittently been coming on prior to this happening... not sure if it is related or not.


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## tireshark (Aug 17, 2014)

I''m hearing that it's probably an issue with the drum brake on that wheel. Never messed with drum brakes before, but i'm gonna watch some youtube videos and have a go at it.


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## r0ckstarr (Jan 8, 2013)

Drum brakes are easy after the first time you do them. Do them once and you'll know how to do them every time. Use the opposite side as a reference of where everything goes.


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## SeniorSitizen (Sep 10, 2012)

On some vehicles getting the drum off can be difficult, even after backing the shoes off as a first step in the procedure. And being yours can't be rotated, hope for the best and expect the worst.

Once the drum is off take a pic of that area and the opposite side for reference. The stuck side may have parts that tried to breed and have pups.


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## tireshark (Aug 17, 2014)

Okay well i got the drum off... it came off surprisingly easy compared to what i was expecting. I hit it with a hammer and it started moving, then pryed it out a little with a large screwdriver and hit it with a hammer till it came off.

When i removed it, the only issue i saw was that one of the brake pads had separated from the shoe and was loose in the drum. 



















None of the springs or anything else appeared damaged... so is it safe to say that the separated brake pad was the cause of my problem?

Never worked on drum brakes before, so here are some basic questions.

1. I'll be replacing the shoes on this wheel... do i need to replace the shoes on the opposite wheel at the same time? Here is a picture of the other wheel... i measured and there is a bit more than 1/4 inch of material left on the pads.

http://i.imgur.com/8ct8Dd7.jpg

2. The drum on the damaged wheel has several small grooves, and one large groove in it... does it need replaced, or will it still function sufficiently? Here is a picture:

http://i.imgur.com/DUFFTpE.jpg

The drum on the opposite wheel feels smooth all the way across it, so i assume it doesn't need replaced.

Thanks for all the help!


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## Bondo (Dec 8, 2007)

Ayuh,.... Do both sides, only a fool would do just one,....

Get a new drum for the bad side,...

'n get Hardware Kits for each side,....
It reasonably cheap, 'n well worth the small investment,.....

Before ya put 'em together, back the adjusters off, the drums will slide on easier,...
You'll need to manually adjust 'em when ya do the job, they'll self-adjust after,....
Turnin' the wheel with one hand, adjust 'em out til ya get some fair scrappin' sound goin' on,...
Then take it out, 'n drive it,...
The shoes adjust on brakin' in reverse,...


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## ChuckF. (Aug 25, 2013)

You can also take the damaged drum to a place with a machine shop in the back, like a NAPA or Pep Boys, and get it turned smooth. You need a second vehicle of course then.

Agree with Bondo on the 'hardware kit', they are cheap, like <$10. Springs there can fly off, never to be found again, or they can break when you try to remove them. I think you should slap shoes on the other side just so they match. It's unlikely that the shoes you buy would be from the same manufacturer or same composition.


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## tireshark (Aug 17, 2014)

Took the drum to an auto shop and they said it could be turned and still be within specs. $15 bucks. EZ-PZ.


I wasn't planning on doing anything with the wheel cylinder, but when i loosened the springs to lift the brake shoes off, the rubber boot and piston spontaneously fell off one side of the wheel cylinder... along with brake fluid of course. Not sure why it fell off like that, unless maybe the brake pad completely separating in the drum dislodged it or something.


Actually i just thought of something... i had to use my truck to haul something, so i put the drum back on with the loose pad removed, and the shoe just having the exposed metal base. I could hear it grinding in the brake drum, but it was already gouged anyway so i wasn't too worried about it. That was the side of the wheel cylinder that popped off... i wonder if driving without a brake pad might have caused it to overextend or something and get loose maybe?


Anyway, maybe i'll get a kit or just a new wheel cylinder... both are pretty cheap at $5 and $12 at oreillys, or even $6 for an entire cylinder on ebay... that is, if i dont just clean it up and put it back like it is. I'd go get a kit since it's already apart, but it doesn't have the pistons.. so then i might as well get the whole cylinder... but then i have to take the brake lines off and all that... not a big deal, but like everything else you go to make a simple repair and there is always something else that pops up to do, which leads to something else, and so on... haha.


Suppose i'll just suck it up and order a cylinder off ebay just to be safe, since the circumstances were a little unusual inside the brake drum for this failure... plus it's only $6.


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## tireshark (Aug 17, 2014)

Someone told me that the wheel cylinders press against the brake pad... so if the pad isn't there, it will pop out. So that explains why it fell off.


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## Brainbucket (Mar 30, 2015)

Wheel cylinders have a spring in it to press on the cups. There is around 4lbs of fluid pressure against the cup to keep it sealed so air won't enter the system. The brake springs keep the cup and pistons from popping out. The outside dust cover also help keep the pistons from popping out but as age hits them, the dust covers get weak. There is a residual valve in the master cylinder to keep fluid pressure on the wheel cylinder but not for disc brakes. Disc have 0 lbs residual pressure. If you put disc brakes on a drum brake system, you have to either remove the valve or install a master cylinder for rear disc brakes or they will drag. Replace wheel cylinders, turn drums, and replace shoes and don't get the cheapest ones or they may MOAN/ make noise after a while when braking. Go at least a step up on shoes. Bleed system.:vs_cool:


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