Squeaking Drums

I have 21K miles on my truck right now. Since it was brand new the rear drum brakes have squeaked when cold driving and just before coming to a full stop. I took it to the dealer and they said that the pads are perfect and it's just the nature of the beast. I've lived with that until now.

A couple of days ago I rotated the tires. I had jack stands under both sides of the rear axle and put the parking brake on. With the parking brake on hard the drivers side wheel was rock solid and didn't move. On the passengers side the wheel has about a 1/2 inch turn play. The other side stays perfect still. You can rotate the wheel 1/2 inch or so both ways before it hits something and stops. It acts like the pads are tight but move between the mounting post or caliper. Maybe the caliper is loose inside.

I am going to stop and get a couple of bolts to free up the stuck drums tonight and check it out. Has anyone had this problem?

What really chaps my hide is that the dealer said the brake pads were OK. No way have those drums ever come off. They are frozen solid. They never looked unless they have some special ultrasonic or x-ray, device that can "see" inside the drum without removing it.

 

just take a metal hammer and beat on the outer ring of the drum, dont hit the weight but It will come off in a few swings that way.

 

Noise in the morning is typical, espeically if the shoes are a semi-metallic composition. I would not worry about that.

The noise when almost at a full stop would usually lead me to suspect that the backing plate needs to br lubricated. There are typically 6 spots where the shoes contacts the backing plate, lube those spots, you'll have to use a screwdriver to move the shoe out of the way to get the lube in there. Also lube any kind of anchor points for the shoes as well.

The parking brake topic, I would adjust that rear drum up a little to where you feel a good, consistent, moderate drag.

There is no caliper in a drum brake system, wheel cylinders apply the hydraulic pressure on the shoes during braking in the drum system.

 

DO NOT use a metal hammer! There is a metric threaded hole on the hub side of the drum. 10mm, I think. Two of them will force out the drum. If you must, a dead blow hammer will work. If you don't intend to reuse the drums, a metal hammer will work, but the bolts are the fastest.

Disassemble and clean all contact points, shoes, adjusters with brake cleaner. Reassemble using 3M Brake lube on all steel on steel contact points(not on drum/pad friction surfaces) and on adjuster. Adjust after reassembly. Should quiet it up considerably.

 

good to know

 

Problem Resolved.

First the minor play moving the tire left and right was due to the parking brake on and not pressing the brake pedal. When the parking brake is on the brake pads can move slightly left and right because there is play on a relaxed the brake slave cylinder.

I removed the drum brake pads and lightly coated the contact points against the housing with some high-temp grease. I haven't had an issue since.

One word on removing the drums. The first time you remove them you MUST use 2 - 8 x 1.25 metric bolts to pry them away from the axle. No amount of banging with a hammer will work. During the assembly of the brakes when new, a sticky paper ring is placed between the drum and spindle holding the lug bolts. I'm sure this is so the drums wouldn't fall off while traveling down an assembly line. This paper tape/washer/gasket type thing does it's job well and NOTHING except inserting the bolts is going to break it free. Do not bang on the drum with a hammer.

 

The parking brake is engaged via cable and linkage and is not hydraulic. It is independant of the slave cylinder.

 

Yes exactly. That's why there is play at the top of the brake pads because the slave cylinder isn't exerting pressure against the pads. The parking brake pushes from cable and not hydraulics.

 

^^ Bam way better than hitting them with a hammer. Don't forget to release the parking brake.