Rear drum brakes dragging

[nuron]

Situation: Right rear drum brake was making noise so I took off the wheel and found that it was dragging at a certain point when the hub was turned. Left rear drum brake spins freely without trouble.

I found that the front shoes of both sides were a bit worn down, but not the rear shoes, so I replaced the front ones with a new set. Now, it's very hard to even put on the actual drum itself over the shoes on both sides!

The adjuster is set way down--so much that the big spring doesn't have much tension on it. I read that a lot of people having problems with assembling the drum is due to not recalibrating the adjuster for the extra meat on the brake shoe. However, I've done all this and I'm still having trouble making the hub spin without drag. Any help?

[fenixus]

check the drum's roundness, some local shops might be able to machine it properly
no other ideas come to mind ... unless your parking brake cable is set too tight, should catch the car at 5 clicks and immobilize it at the 8th, loosen it up a bit for now?

[carsrus]

You dont have the drum adjusted all the way in. The shiny gold thing inside the spring needs to be all the way to the right against that ring of teeth.

You were able to only buy 2 out of 4 brake shoes????

[nuron]

Originally Posted by fenixus

check the drum's roundness, some local shops might be able to machine it properly
no other ideas come to mind ... unless your parking brake cable is set too tight, should catch the car at 5 clicks and immobilize it at the 8th, loosen it up a bit for now?

Actually the parking brake is on the loose side--I have to yank it really far up to stop the car.

Originally Posted by carsrus

You dont have the drum adjusted all the way in. The shiny gold thing inside the spring needs to be all the way to the right against that ring of teeth.

You were able to only buy 2 out of 4 brake shoes????

That gold thing is adjusted so far in that the spring's tension is barely pulling on the shoe. I was under the impression that there should be some stretch to the spring anyways--there is currently no stretch to it.

The rearward brake shoes almost have as much meat as new shoes so I didn't see a point in replacing them.

[fenixus]

I think the real question is why only one side of drum shoe is worn out and the other not. I think there is something that's supposed to spread them out evenly and press to drum's surface evenly on both sides when brake is applied. that thing is probably failed.

I've never heard of anybody being able to get only 1 drum shoe ... I thought they sell them in sets for both rear drums (both front and rear shoes for each)?

[nuron]

Yeah you're right on the even pressure part. Maybe the piston?

I never said I bought one shoe. My box came with four.

[pmesfun]

I'm not that familiar with drums, but could it be the wheel cylinder?

[fenixus]

yeah could be. I think there are 2 pistons moving in opposite directions as pressure is applied. seems only the one on worn shoe side works actually. the other might be stuck.

Originally Posted by nuron

Yeah you're right on the even pressure part. Maybe the piston?

I never said I bought one shoe. My box came with four.

[nuron]

Bump. Any more ideas?

[ajkalian]

I don't have drum brakes on my car, so I can't check to be sure if this is still true on a Camry.

But on the cars that I did have that had drum brakes all around, the brake shoes were different from the front to the back. Not the front to the back wheels, but within each wheel one shoe had more brake lining than the other. It was important to put the one with longer brake lining either in the front or the back. Mix them up and you get premature and uneven brake shoe wear. Sorry, that I can't remember for sure which went where. I think the longer one went in in the front position, but I could be wrong. If your brake shoes have the same length lining material, then this doesn't apply.

Getting the drums on a new set of shoes is sometimes hard, because of a lip that is formed within the old brake drum from the wear of the old brake shoes. You won't have this lip if you have your drums turned. But if you just reused the old ones it will be there. You need to back off all the way on the star wheel to get the drum on. Don't worry about the spring tension, the springs won't fall out of the grooves. Once the drum is on, there will be a lot of distance between the actual drum surface and the shoes, since you backed off the star wheel to clear the lip on the brake drum, so you will have to adjust the star wheel a lot to take up the space. Turn the star wheel to when the drums just start to make noise, that's enough. Drive around a bit to seat the shoes, and jack up the car and turn the wheel and re-adjust the star wheel until the brakes drag just a bit.

But before you do any of this. Get a brush and clean out all the dust that has built up inside the drums. A 1" paintbrush works well. Get a fan and position it to blow the dust away from you while you do it. A dust mask is a good idea when doing this. Then once all the dust is cleaned up, get some brake cleaner, and spray everything except the brake cylinder boots. Then put everything back together.

.

[Hajoca]

Drum brakes there is leading shoe (lining) and training shoe. Rotation of drum against the leading shoe will cause the front one to wedge itself tighter against it to create more friction, training shoe does not. That is why one shoe wears more.

I reversed my front and rear shoes by removing C clip and pressing out pin and put it on the other shoe.

[nuron]

I found out why!



When I first took off the drum, the spring hooked on to that second hole from the top. Turns out the spring needed to be hooked onto the THIRD hole down. That's why adjusting the star wheel all the way in didn't help because there wasn't enough tension pulling both the shoes together. I only put it back on the second hole because that's how it was when I first took off the drum. I guess the previous person who worked on it didn't replace it right and the drums must have dragged for a while before wearing down enough for the drum to spin freely!

[bolink654]

Originally Posted by Hajoca

Drum brakes there is leading shoe (lining) and training shoe. Rotation of drum against the leading shoe will cause the front one to wedge itself tighter against it to create more friction, training shoe does not. That is why one shoe wears more.

That's what I've always thought, and seen, too. Front one always wears faster than the rear

[TedL]

One other possibility. My son's 97 with rear drums used to get noisy due to rust buildup on the exterior of the drum rubbing against the backing plate. Solution was to tap the area with a hammer to break off the rust buildup.