CarTalk.com Blogs Car Info Our Show Deals Mechanics Files Vehicle Donation

Replaced drum brakes recently: high pitched squeal when coming to slow stop

so recently i took on the endeavor of changing my drum brakes myself and it was a total pain in the ass and i hope i never have to do it again. Anyways I’m confident i got them on the way they’re supposed to be, I made a post yesterday asking about squishy brake pedal it turns out i just didn’t do a very good job bleeding the brakes when i put in the new cylinders. Anyways I get that done and I’m feeling good about how hopefully i won’t have to mess with the rear brakes or wheels at all for that matter any time soon, but now I’m driving everything seems good but I notice a high pitch squeal when coming to a slow stop. It doesn’t seem to happen when going at a decent speed and the noise goes away quickly when stopping, but going real slow or slowly stopping there’s a high pitch squeal and i assume it’s coming from the back as that would make the most sense being the side i’ve worked on recently. Now I will say that when I retightened the drum brakes (they originally weren’t tight enough) i tightened them maybe where the drum was a bit more tight then how it’s supposed to be (it was still turnable just somewhat tight) this was the hope that it would just wear in itself and not be an issue could this be what’s causing the squeal? How concerned about this should I be?

New drums? Or did you have the old ones turned? Or did you put the old ones back on as-is?

sorry same old drums i replaced the shoes, springs, and cylinders

Too late now I suppose, getting the drums resurfaced could have helped, is the squeal from the rear?

yes i believe so

Can you live with it until the pads mate with the drums? Just as a side note every garbage truck in our fair city squeals at every stop, maybe 100’ apart.

1 Like

I can definitely deal with it if it’s not a big deal. If the noise is the only issue then honestly i don’t mind at all i just wasn’t sure if this could be a sign that something is worse

The brake backing plates should have been greased at the raised dimples that the shoes rest against as they move. I don’t know why no one seems to do that anymore.

3 Likes

My guess is this problem will gradually go away by itself. I expect the shoes just haven’t matched up to the drum surface yet. When I do that job myself – and I agree it can be quite a challenge, big learning curve if you’ve never done it before .-- while the drum is removed I sand the inside surface with some 180 grit sandpaper, either in circular patter or just across the drum surface. The sanding grooves are 90 degrees to the direction the drum surface is moving past the shoe surface in other words. That seems to help the shoes bed w/the drums a little faster. Sanding the leading and trailing edge of the shoes can be helpful as well, but I’ve never had to do that myself. As pointed out by @Rod_Knox above it’s important to lube the shoe/backing plate surfaces with brake grease. Whenever I’ve purchases shoes there’s a little packet of brake grease in the box. Where these lube points are located is explained in most repair manuals.

One more thing: avoid extra-hard stops if possible during the bed-in process .

Usually it isn’t overly difficult to remove the drums (I mean once you get them removed in the first place, which can be a bear the first time). If I had that problem I’d probably just remove the drums for a look see, and maybe do a little sanding while they are removed. Some manufacturers , Toyota for example did this for my Corolla , they put threaded holes in the drum so you an insert a couple of bolt and push the drum off with little bother at all. Make sure there’s no brake dust or sanding grit left in the drums or on the backing plate area before reinstalling. Brake dust getting between the shoe and the drum can make a squeal.

The rear wheels aren’t getting really hot after a short drive w/out much braking involved, right?

Ok, you can admit it. You actually found this job, while a challenge, to be pretty fun and can’t wait to do it again now you think about it right? … lol …

1 Like

I actually did do that I put anti-seize on the contact points, but it may be worth mentioning that the left wheel backing plate the bottom contact points seemed more worn than the others.

I did put anti-seize on the contact points, one thing maybe worth mentioning that I didn’t put in my original post is that on the driver side wheel the lower contact points on the backing plate seemed more worn than the ones on top (i didn’t think it would be too big an issue). As for hot wheels I don’t think so, but I have noticed (this was before I even changed the brakes and stuff I’ll have to remember to check again next time I drive anywhere) that sometimes the metal part of the rear wheels would be hot after driving a bit (again this was before I changed anything I kind of ignored this issue tbh and I’ll need to remember to check again). As for your last question I don’t know how it is for most people but putting the wheels back on today I was hoping I wouldn’t need to take them off again for a very long time, that being side it probably was a good learning experience overall.

I replaced the rear shoes on my Corolla last summer, and there was some minor problem after it was all back together. I forget what it was at the moment. Anyway I resisted removing the drums again, but decided just to bite the bullet & do it to see what was causing the issue. It took like 10-15 minutes to resolve the problem, very little effort, so my resisting removing the drums again was really not necessary.

If you put the rear drums back on as is, the wear ridge is going to prevent you from removing the drum unless you loosen the brake adjustment. To do that you will need a small screwdriver in addition to whatever tool you adjuster the brake with.

The small screwdriver will be used to hold the lockimg lever up while you turn the star wheel the other way.

1 Like