Rear brake shoes

[Sanitarium 73]

Hello to everyone, I know I havn't posted in a long time, but I've been busy with my job at a GM dealership.

Anyway, I'm having an unusual problem with the rear drum brakes in my '88 Crown Vic.

I had let it sit for about a month, and when I drove it again, one of the wheel cylinders started leaking badly. I replaced both rear wheel cylinders, and since i was in there, i went ahead and did the rear shoes too.

they were fine for a couple days, but they would keep expanding outward, and drag on the drums. the rear brakes were overly sensitive and would lock up easily. I know for a fact that the rear shoes developed a crack.

This morning, right before i exited the driveway, the passenger side rear wheel locked up completely. I'm assuming one of the shoes broke completely. What should I look for before diving into this? it was my first brake job, and I do have access to tools. Also, should the larger brake shoe be towards the back of the car, or the front?

Sorry to ask so much, and I appreciate any replies.

[mrltd]

Might be a bad hose, could be something wrong with the adjusters or master cylinder.

[85crownHPP]

maybe your star wheels are backwards??? they could be different left and right. you sure they are getting tighter? the drums become hard to remove??? becuase they can lock up for a few reasons.

[Blaze86Vic]

A wheel just locking up is a sure sign something is backwards. The automatic adjuster should have a metal plate that is spring loaded against the notches. Make sure that is on and working correctly at preventing the adjuster from expanding all the time.

[Sanitarium 73]

After I got home from work, I raised the rear corner of the vehicle to try to remove the drum. I had to knock it off with a hammer, but upon inspection, I saw that about 1/3 of the pad had actually seperated from the metal part of the shoe, and became stuck on the shoe in front of it.

the car is now movable, and I'm going to try to drive it to my work tomorrow so I can attempt to fix it.

Both adjusters are functional, and the spring loaded metal plates seem to fit tightly against the star wheel. I do not believe I switched the adjusters, becuase I did one side at a time. you can pull the metal plates away with little effort, I'm unsure exactly how "tight" it should be.

I'm pretty sure something is causing the shoes to press outwards against the drum for some reason. It is most noticable in a drive through, or letting the car idle itself forward from a stop. You can hear an audible noise, almost as if the emergency brake is on. I am unsure if the emergency brake could be involved, but I have never used it since I've owned the car.

Could the brake proportioning valve be involved? I tried to pick one up yesterday, but I learned it was a dealer-only part, so I wanted to ask before making a possibly unnecessary purchase.