I recently replaced the drum brakes and shoes on my girlfriends Corolla. After the repair, the right rear side has an audible knocking/thumping sound that only happens when you press on the brake. You can also feel the thumping through the brake pedal.

Anyone run into this issue before? I pulled the drum off and everything looked fine. My only guess is that there is something going on with the adjuster. Either is not working correctly, or I didn't adjust it out enough?

If for some reason the drum is warped it'd cause vibration under braking, that or maybe the drum or shoe surface is off. They're new, but shìt happens. I know on older cars you're supposed to take off quickly in reverse and then slam on the brakes to self-adjust, rather or not that's the case here in a newer car I don't know. Does it make the noise when using the emergency brake?

This post has been edited by Box: Nov 25, 2013 - 1:44 AM

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This post has been edited by Box: Nov 25, 2013 - 1:44 AM

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I believe I tried just the ebrake and it did make the noise.
I didn't try reverse and brake slams. From my understanding it just auto adjusts as you press the brakes, and continuously adjusts as the shoes fade.

This isn't my exact car/video but I found a video on youtube that pretty much has the same noise.
https://www.youtube.com/watch?v=Oc3BmtLJ2cY

The adjuster should do it's own thing and adjust over time, but I think the procedure I mentioned was for after installing new shoes and/or drums. I can't remember exactly, it's been years since I've owned that Cadillac now. Can give it a shot, but I'm thinking it may be a surface issue from the factory. If something were wrong with the adjuster, I'd think it'd be visibly noticeable.

A) this is not celica related thus #wrongforum

B) probably have a retainer/spring that isn't on right or something is loose letting it rock inside the drum. Make sure you've properly set the adjustment to start with and that everything is locked in and drum is fully seated.

C) I have never heard of going in reverse and slamming on the brakes...and i've done several drum changes.

This post has been edited by playr158: Nov 25, 2013 - 1:07 PM

It's a Corolla, so odds are it uses the same or similar setup to the Celica ST. Close enough.

That'd be something you could see though, unless he's just somehow overlooking it. Hmm, could take off the driver side and look at it for comparison.

You haven't been around old domestic cars then.

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All of the springs are correctly installed and there is nothing loose. I set the initial adjustment by rotating the drum and adjusting until it felt like there was some resistance.
I can only guess that this is happening because the rear shoe is not fully contacting the drum, but if that was the case, it should have adjusted itself by now. Maybe the adjuster is not working correctly or stuck. This seems like a really common issue that should be on page1 of every repair manual.

This post has been edited by lagos: Nov 25, 2013 - 2:52 PM

The adjuster repair kit is under $10 off Rock Auto, so may just want to go ahead and replace it.

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Yeah, I guess I was hoping for a confirmation before I start taking the shoes apart in 40 degree weather.

That's still shorts and t-shirt weather for me.

I don't know about slamming in reverse, but the spring does re-tension (reset?) when reversing.

This post has been edited by SwissFerdi: Nov 26, 2013 - 8:17 PM

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I don't really see how that works. Looking at the shoes, it seems like when you press the brakes, the little adjuster moves with the shoe and gets incremented by one notch at a time so that when you let go of the brake, it is as close to the drum as possible without touching. This would work the same way in both forward or reverse operation.

Now that I think about it, I believe the problem is that those adjusters are fairly old and not well lubricated, so they are just not incrementing as they should. If I just pull the drum off and make the adjustment tighter, the noise should go away but would probably eventually come back as the shoe wears down over time.

Hmm, could try cleaning and mildly sanding down the adjuster components and then lubricating them upon re-installation. Then again it's cheap to replace, just have to wait for them.