Brake caliper problem?

kjp · #1 (**permalink**) 07-14-2003, 10:40 AM

Every once in a while, when braking, I hear and feel a slight grabbing/grinding noise coming from the rear end. Upon acceleration, sometimes the car may, for lack of better words, 'stick' a very slight bit before moving forward normally. After a few seconds of movement, everything turns as it should.

I have purchased a new hardware kit for the rear (and front) brakes and intend to install these this week. The rotors look OK, no major wear or grooves, and the same for the pads. I may install new pads while I am working on the calipers though, especially if one is hanging on me. I checked the parking brake, and it seems to be releasing normally.

Brake fluid was changed out this Spring to the ATE Super Blue.

Am I looking at a bad piston in one of my calipers? Any way that someone knows how to test for this?

Thanks in advance.

Mr. C. · #2 (**permalink**) 07-17-2003, 08:56 AM

Hello Ken,

Sorry you are having to get out and get under this weekend.
I know of no way to test the calipers other than visually !
Jack the car up onto good jack stands. (You will need someone in the car) Take the wheels off and get down next to one of the calipers. Turn the rotor and get a feel for force reguired to turn it. I sue a 1/2 inch socket breaker bar on the lug studs to help turning. Have someone step on the brake and make sure you cannot turn the rotor while the brakes are on. Have assistant release the brake and try to turn the rotor. If it sticks and turns hard try brakes on and off a couple of times to be sure and if it is still sticking, it will have to come off and be overhauled.
I read that the piston can be freed by repeated sticking and unsticking but I do not believe in short cuts with brakes. Also If one caliper has sticking pistons, I would overhaul at least both on that axle. But the car is up in the air, you are dirty already, why not do all four.
I expect that you know to use only brake fluid or genuine brake cleaner when doing this work. Also brake fluid is nasty and I have recently taken to wearing surgical gloves when using the stuff.
Good luck
MrC

kjp · #3 (**permalink**) 07-22-2003, 07:10 AM

Mr. C -

Thanks for the tip, turns out the passenger side rear was sticking a bit. The replacements for the rear axle are on order. I also do not believe in shortcuts on the brake system. You can always make a car go fast, but you also have to stop.

Thanks!

kjp · #4 (**permalink**) 07-29-2003, 08:16 AM

After some more testing and examination, I believe my calipers were OK. But, I installed the set of new ones to be on the safe side. The 25 plus year old units should probably be reconditioned anyway.

Same problem - but at least now I can rule out the brakes. Created a new post in this section to cover the next steps.