gunslinger1_1

Hi gang,
First time poster. I tried to find an answer using the search, but I didn't find anything relevant.

I have an intermitten squeak/rubbing sound from the rear driver side brakes. It has drum brakes. It happens only at low speeds (well...that's the only time I can hear it, anyway).

I thought the new drums I got from autozone may have been warped, so I replaced them last weekend.

I jacked it up, and spun the wheel. It seemed to catch at the same place with each revolution of the wheel. I took off the wheel, and spun the drum assembly, and again, it rubbed at the same spot.

I took off the drum and saw that the the shoes closest to the wheel cylinder were polished, so I roughed them up with a wire wheel and ran the wire wheel around inside the drum to remove any glaze.

The springs holding the shoes together seem to be pretty strong.

I took it out for a test drive, and the squeak was gone for a little bit, but by the time I had gone a mile, it was back...very quiet, but back.

Any thoughts? Could it be a bad wheel cylinder?

Thanks in advance.

Bob

The_Mechanic_33

with drum off push wheel cylinder piston in on both sides to see if they are frozen and/or slightly press brake pedal (piston will come out of bore be careful small press of pedal). make sure adjuster is in proper position.
please lets us know what happens.

The_Mechanic_33

with drum off push wheel cylinder piston in on both sides to see if they are frozen and/or slightly press brake pedal (piston will come out of bore be careful small press of pedal). make sure adjuster is in proper position.
please lets us know what happens.

gunslinger1_1

Both pistons move. I can press on one piston, and as I press the other piston comes out. I also tested with a light pressing of the brakes. The top piston came right out, but the lower piston was more sluggish.

How can I tell if the adjuster is in the correct position?

Thanks for your quick response.

Bob

The_Mechanic_33

Drum Brake System Notes Notes

gunslinger1_1

That looks like what I got. Everything looks to be in order based on the diagrams.

I see the adjuster cap...I assume that once I have the drum in place, I can pop that cap off to adjust the brakes a bit. Would that help?

I also notice that the e-brake spring is under a slight tension...sorry for my ignorance, but is that normal?

Every other car I've had has disc brakes front and back; this is my first experience with drums.

Bob

mightymoose_22

Your parking brake needs to be adjusted after replacing the rear brakes. As the pads wear down the pbrake automatically adjusts, however when the pads are replaced you need to reset it.
I believe you will find a tension screw near the handle. Give it several turns to loosen it up. Then, to reset the tension, pull up on the handle several times while rolling backwards slowly. When the pbrake grabs and holds the wheels firmly then you know you are set.

gunslinger1_1

OK...I've adjusted the parking brake, but there was no change...I looked on the autozone site, and found that they suggest adjusting the brakes (it makes sense), but I've never done that. The information there talks about using special brake adjusting tools. Is this something a DIYer can do, or should I bite the bullet and take it to a shop?

Bob

mightymoose_22

The suggestion given above about a bad cylinder sounds most likely at this point. Maybe one of those pistons is not going all the way back in?
With the wheel off, use your fingers and hold the pistons in the cylinder while someone else steps on the brake gently.... make sure you can feel both pistons pushing out, and when the brake is released feel for a smooth return back into the cylinder.
Other than that... confirm that you have the right pads on the car and that your springs are good.

rhandwor

A new wheel cylinder is fairly cheap you can also hone and put in a kit. The shoes have a front and a back shoe the pad length is different. Are they installed correctly. Pull the drum on the good side. Look at the shoes and if the shoes are installed the same way. You may need to use a file where it is hanging up if it isn't centered. Their is an adjuster for the brakes at the bottom adjust it up and check where the pad is hitting then you know where to file. Loosen the adjuster put on the drum remove the rubber pad and use a screwdriver tighten the adjuster by turning the wheel. Rotate the drum and when the pad starts rubbing stop. Put the rubber plug back in. The self adjuster will do the final adjustment.

curtis73

+1 on the bad cylinder. It could also be made worse by dirt, rust, inclusions, and other junk in there. If the drums have a spot that has been overheated, it could have shoe friction material cooked on it that can't be removed with scuffing or a wire wheel. It cooks it so hot it crystallizes it into a stuff called cementite, and its actually harder than the name suggests.

gunslinger1_1

rhandwor,
I'm not quite understanding this statement:
Do I file the shoes or the drum? I assume the shoes, but I could be totally wrong.

Curtis, with the inclusions, is there any way to get rid of them without turning the drums (high speed rotary tool with diamond bits...)

Thanks everyone!

Bob

rhandwor

If you arc your pads you don't have this problem. The length of the pad if too long some times will hang up. So you file this edge taper it so it don't want to catch. Take some emory paper and sand any rough spots on the drum. As you have two sets I don't think it happened to both. The adjuster is on the bottom turn it in so the drum goes on freely. Then adjust it outwards so the pads just touch as you rotate the drum. I'm talking about filing the front edge of the pad bonded or riveted to the brake shoe. As you would rotate the drum this edge.

gunslinger1_1

Arching the brake pads worked! Thanks so much!

Bob