"Stuck" Caliper

mark · Mar 7, 2017

So this past month, when we actually had some snow in the lowlands, I had a rear caliper on my junk eventually freeze up (stick) as I was tearing around the neighborhood. Fast forward to tonight I actually clean the garage enough to pull it inside and tear it apart. I was able to get the piston to push back in with a C clamp and got it all free'd up for a little maintenance (whats that?)

So what causes a caliper to freeze up like this? Is it condemned or just general junk and gunk on the bolts and slides and a good cleaning and it should be good to go? Everything was pretty crusty from dirt and mud. The rigs been sitting with little real use for the past 12+ months, not so much major rust. I probably knocked 10lbs of mud and dirt just out of the rotors :redneck:

Clean and go? Or should I look at a new set of calipers. They are inexpensive, but I'm a cheap bastard and its just wheeling junk, and I hate beading brakes.

Standard 1/2T-3/4T GM calipers on a home-brew rear D44 disc brake conversion. :beer:

KarlVP · Mar 7, 2017

In the past I have pushed the piston all the way out to clean up the inside with mixed results. About 70% of the time i was able to get the piston back in.

Mostly ford stuff. I've never disassembled GM calipers.

I would take it all the way apart and see if there is crud inside. Reassemble and if it doesn't work, you would have gone and got a new caliper anyways.

boardbysled · Mar 7, 2017

For the $20 it costs for a 1/2 ton chevy caliper, I'd just replace it.

crash2 · Mar 7, 2017

A caliper is a caliper--they are all the same except the e-brake styles..

Replace it unless you have a nice hone and new seals.

Corey Y · Mar 7, 2017

The inside of the pistons rust and cause them to stick. You can take the piston out, clean the rust off and reassemble or just trade it in for a new caliper.

JOOP · Mar 8, 2017

A couple of things cause pistons to stick.
1. Nasty brake fluid
2. If the rubber dust cover is torn and dirt gets in there, the piston will freeze.
3. If the piston is plastic they crack and expand, equals stuck

Also frozen slide pins or dirty slide pins can cause the caliper not to retract.

Just get a new caliper.

crash2 · Mar 8, 2017

Crazy Daze said:
The inside of the pistons rust and cause them to stick. You can take the piston out, clean the rust off and reassemble or just trade it in for a new caliper.

I have seen more issues with undersized pistons and bulged seals causing them to stick than anything. typically if there is rust on the piston the bore has the same.

1982cj7 · Mar 8, 2017

Typically if there is rust on the piston it should be replaced, if you clean it, it will just rust again.

4xguy · Mar 8, 2017

Im kinda leaning towards replacing too since it shouldnt be too expensive. Personal experience Ive had my 96 for 17 years and ive replaced the front calipers about 3-4 times. It does sit a lot and it will break free after some driving and a few hard "brake checks", but seems that it just feezes easier the next time until it eventually never fully releases.

mark · Mar 9, 2017

Agains my "IH guy" cheapness, I picked up a new set of calipers on the way home today. If nothing else, I get new pins and sliders, which was probably 1/2 my issue.

Now I just need to make time to get them on and tested before next weekend. Might actually go wheeling..... with I couple old IH cronies at that.