mustangman101

my buddy has an 88 grand marquis and the back passenger side brake locks up when i am coming to a stop. im not driving like a mad man or anything just from like 30 stopping for a stop sign. i recently put new brake pads, rotors, calipers and all on the front. anyone have an idea what could cause the back brake to lock up like that?



also the car had a surging idle. i have checkede the IAC, i also got another one from the junkyard and cleaned it upi but that didnt work either. anyone have any other ideas as to what could cause this?

Zman

2 things, either sticking brake cylinder or the springs are weak that pull back the shoes. Cylinder most common.

mustangman101

what does the brake cylinder look like and where is it located????

Zman

inside the rear brakes, take the drums off and you will see a round cylinder that pushes the shoes out and then the springs retract the shoes when the pedal is released. Usually 2 bolts hold it on on the back side of the backing plates. they are cheap at the parts store.

91Notch

They also could be adjusted too tight or there could be a faulty brake hose.

mustangman101

there wasnt a problem before so i think it could be the cylinder

Adrenalin

I would agree the cyliner is probably bad. I think they may be about 5 bucks or so for one... It's been a while since I've bought one.



It's hard to say about the idle. If it's not the iac, you could have a vacuum leak.