96 grand am rear brakes

[soccer dude]

when i gently apply the brakes at a slow driving speed (20km/hr) like in a parking lot the right rear tire appears to lock up,and the rear of the car squats down.have had it in for repairs but no luck,if i drive 50km/hr and slam on the brakes it will fix the problem until the next time the car sits for any amount of time(over night)

[GTP Dad]

Welcome to AF!!

Does your car have antilock brakes? If so you may have a malfunctioning sensor that is causing the wheel to lock. Have the vehicle scanned with an ABS capable scanner to see if there are any codes. If you do not have ABS the issue could be due to a bad brake line that is causing the fluid to stay in the system too long when you release the brake pedal and causing the wheel to lock. This can also be the cause with ABS!

[3100]

your case is called "grabbing brake" most liikely there is some grease on the shoes or drums and believe it or not it will cause that. You have to make sure you do not touch friction surfaces with greasy hands. Remove drums and use some brake cleaner to clean friction material from oil and grease.

[soccer dude]

i have tried replaced flex lines,replaced sensors and cleaned pads but none have solved the problem, just noticed and this i think reduces the the number of things that could be the problem that it also locks up (pass. side rear) when gently applying the e. brake

[3100]

hey maybe you could have an out of round drum, try switching drums and if grabbing changes to the other side now, you know that the drum was problem. reply

[hufhouse]

My guesses, in order:

1. Brake cylinder is leaking brake fluid lightly onto the drum. If this is the case, it would probably happen the first few times you stop, then the brake would be fine the rest of the ride.

2. Out-of-round brake drum. If this is the case, it would happen all the time.

[3100]

I thought about the same thing also, but since he tried everything why not try swapping them it will not cost him anything. Who knows what is going on in there when things heat up Try breaking hard in reverse several times also. Or just take a picture of that brake setup that you have now and post it here let see maybe something was installed wrong. I hope you did not install both secondary shoes on one side somehow. Secondary shoes go towards the back,and primary go towards the front. Secondary shoes are thicker. So check that also. Is there any oil leaks inside of the drum?

[soccer dude]

i switched the drums even though they are almost new , guess what ,the problem is now on the other side.since then i have replaced the drum and all is good. thanks for all the tips

[3100]

Originally Posted by 3100

hey maybe you could have an out of round drum, try switching drums and if grabbing changes to the other side now, you know that the drum was problem. reply

so I was right
hufhouse did you hear this

[hufhouse]

Originally Posted by 3100

so I was right
hufhouse did you hear this

Awright. Looking back at this thread, I really think I didn't read your post before I posted mine, or I wouldn't have repeated you!

[coze]

I have a 97 Grandam that had the same issues after changing my rear shoes. Come to find out the new shoes were my problem, to soft maybe. I bought the ( Wagner Thermo Quiet shoes) and this fixed my problem. I hope this helps.