What causes stuck calipers?

[BD2003]

My GFs buick is a disaster. She had one of the calipers replaced (Yes, I checked, they did it) for sticking 2 months ago, since it was pulling to the side, etc.

The same wheel now has a sticking caliper again, and this time its sticking so hard that her FL brake is smoking.

What could be the root cause?

 

[Jahee]

Grit? Rust or oxidation anywhere??

Just guesses.

 

[Hyperlite]

crap in the brake fluid? problem with the master cylinder?

 

[flyfish]

It is actually the brake line that is causing the caliper to stick.

There is a rubber section of brake line at the caliper. Over time this rubber line will actually start to disintegrate from the inside out. The rubber particulate then is forced into the caliper causing it to stick. If you get new caliper and don't replace the line I bet it will stick also.

 

[Hyperlite]

There is a rubber section of brake line at the caliper. Over time this rubber line will actually start to disintegrate from the inside out. The rubber particulate then is forced into the caliper causing it to stick. If you get new caliper and don't replace the line I bet it will stick also.

correct

 

[FeuerFrei]

grease teh caliper slides

 

[nakedfrog]

Driving through glue puddles?

 

[43st]

I had this issue on a Mazda I owned a while ago. In my case it was always one of the rear calipers and it was the emergency brake arm that was the issue, it would get snagged on the caliper body. To unstick it I could reach under the car and give it a light push up and it would 'pop' open, releasing the brake. My solution was to just stop using the emergency brake, all was fine after that, just had to be careful how I parked.

 

[BD2003]

Originally posted by: flyfish
It is actually the brake line that is causing the caliper to stick.

There is a rubber section of brake line at the caliper. Over time this rubber line will actually start to disintegrate from the inside out. The rubber particulate then is forced into the caliper causing it to stick. If you get new caliper and don't replace the line I bet it will stick also.

Ya, I figured it had something to do with the lines. Can this caliper be saved or will that have to be replaced again?

 

[flyfish]

I would demand a new caliper and brake line.

And yes, ask that they grease the caliper slides also.

Also, don't let your GF take her car back to that shop.

 

[Black88GTA]

Originally posted by: flyfish
I would demand a new caliper and brake line.

And yes, ask that they grease the caliper slides also.

Also, don't let your GF take her car back to that shop.

The bolded statements are a bit contradictory

But I agree, it's probably the line causing it. Replace the other one while you're at it, as its condition is probably similar.

 

[Zenmervolt]

How old is the car? Usually brake lines don't start deteriorating like that until 15-20 years old. Definitely a possibility though if the fluid hasn't been changed every two years.

If the caliper was simply rebuilt and not replaced, it's possible that the problem is not in the piston, but in the bore and that they shop didn't clean it well. It's also possible that they used a rebuilt unit to replace the sticking one with and the rebuild quality just wasn't there. Also, check the pads, if the pads are worn too far, the piston can be pushed out farther than it should be and this can cause it to stick as well.

Just throwing some other ideas out there.

ZV

 

[IGBT]

..some of the late model oem calipers were made out of plastic and would distort and melt under severe service. If you replace the calipers get Moog or Bendix all metal calipers.

 

[Squisher]

Originally posted by: BD2003

Originally posted by: flyfish
It is actually the brake line that is causing the caliper to stick.

There is a rubber section of brake line at the caliper. Over time this rubber line will actually start to disintegrate from the inside out. The rubber particulate then is forced into the caliper causing it to stick. If you get new caliper and don't replace the line I bet it will stick also.

Ya, I figured it had something to do with the lines. Can this caliper be saved or will that have to be replaced again?

It's been years since I rebuilt a caliper. I imagine you could remove the piston and clean it and the caliper throughly. A little 1500 grit wet sand paper couldn't hurt. They used to sell rebuild kits in case anything is fubar in there.

 

[OrganizedChaos]

if it has slide pins or something similar anti-seize the crap out of them.

 

[BD2003]

Originally posted by: Zenmervolt
How old is the car? Usually brake lines don't start deteriorating like that until 15-20 years old. Definitely a possibility though if the fluid hasn't been changed every two years.

If the caliper was simply rebuilt and not replaced, it's possible that the problem is not in the piston, but in the bore and that they shop didn't clean it well. It's also possible that they used a rebuilt unit to replace the sticking one with and the rebuild quality just wasn't there. Also, check the pads, if the pads are worn too far, the piston can be pushed out farther than it should be and this can cause it to stick as well.

Just throwing some other ideas out there.

ZV

The caliper was replaced. The shop she previously went to closed down, but he was a honest guy.

I doubt the brake fluid has EVER been replaced, so it wouldnt surprise me all too much.