Caliper sticking issue.

adamvf · December 9, 2013

Hello GM-Truck community! I joined in hopes of garnering some insight and advice regarding my truck issue. I have read through a few threads already and have searched the internet elsehwere trying to find possible causes. My situaiton does not appear to be unique, I humbly request assistance. I have a few seperate but related questions about my problem.

I have a 2004 Chevrolet Silverado 1500HD 4WD 5.3 V8 truck. I am having an issue with the brakes sticking. Before my first attempt at fixing the problem the brakes would stick all of the time on the front wheels only. Foolishly thinking that the calipers were bad I replaced the calipers, pads and rotors. Only after I made this purchase and had work performed did I learn that most caliper problems are from secondary issues.

The problem: After the repair was made the truck seemed to be braking fine. The brake pedal did not feel exactly right, but I pressed on. After about 10 miles or so of highway driving, the brakes began to stick on their own with little or no pressing of the brake pedal. The steering wheel and truck would shake. After stopping for a time, both front wheel rotors were very hot. The back wheels seemed to be fine. The same problem was back much to my frustration.

After sitting for a couple hours with everything cooled down the truck seemed to be okay again. I'm guessing the caliper pistions eventually retracted. The brake pedal still felt a little stiff, but it drove fine without issue. At harder stops I would have to press the brake pedal down harder then usual just to get the truck to slow down. This particular phenomenon is very odd. After a few miles the front brakes would again stick, the rotors would again be hot.

Questions:

1. With the caliper came a few replacement parts. Inside were two bolts or slide pins as I believe they are called, a washer for the brake line, two rubber boots for the mounting bracket and two black rubber tubes that are about 2 inches long or slightly smaller.

My uncle performed this work, I watched, helped and learned. I know that I would have been better off at the start by consulting a certified brake technician, but in the interest of saving a few bucks this was the route I chose. He insisted that these black rubber tubes were supposed to fit over the new bolts that came with the caliper to "prevent it from moving around." From what I have read calipers are supposed to float and slide around on lubed bolts. So he lubed the black rubber tubes and bolt. He slid them on to the very top of the bolt with a lot of resistance. It took a while to get them on. I got a suspicious feeling that this was not right, but I ignored it and we continued.

The caliper was put on the bolts were slid into place. The bolts initially did fit or slide easily inside the mountaing bracket because of these rubber tubes. So he fenagled, pressed hard, twisted and even beat one until it went in. They were tightened and that was it. I thought about removing the bolts, removing the rubber pieces and lubing it back up for remounting.

My questions regarding the tubes are this: Was that the correct procedure? If not, what are the black rubber tubes exactly for? Are the bolts supposed to be bare?

2. What other potential problems could cause my calipers to stick and make my brakes drag?

Sorry for the long post. I just trying to be thorough in figuring this out. Any help, advice, insight is greatly appreciated. I'll check back regularly.

-Adam

brucelimerick · December 10, 2013

I have never had rubber tubes come with a brake kit. Sounds like they are protective shipping pieces. The pins slide into the other side of the caliper with nothing on them exept the high temp grease. They are supposed to be bare. They are what is causing your calipers to stick. You are going to have a real b*tch of a time as these rubber pieces have probably melted inside the caliper bore. You may get away with using a proper sized drill bit to clean the holes but even with 1/64" increments you might not get the right size. When you are getting into new territory with brakes just do one side at a time so you have the other side to refer too. You may have to by new rotprs again if you can't get them to slide freely. The pins and calipers have to slide freely, there are no springs to make them retract, just the decrease in pressure. They always slightly touch the rotor. If they stick they heat up fast. I have had sticking pins before and at night when you stop you can see the rotors glow.

efritz · December 10, 2013

The black rubber tubes you speak of are a cover for the slider to prevent corrosion and dirt intrusion, the pin goes inside of them between the caliper and brake mounting bracket. The head of the bolt holding the caliper on should rest against the caliper. The fact that your brakes are remaining applied sounds like a hydraulic issue if the calipers are new. Did you replace the rubber flexible hoses? Occasionally they will collapse internally and leave fluid pressure on the calipers. Whatever you do, don't drive the truck with serious brake problems.

gmtech4 · December 10, 2013

omg....

brucelimerick · December 10, 2013

Seems to be a bit of confusion here. The rubber boots that were mentioned, corrugated, go between the caliper and the pad bracket protecting the exposed end of the pin. There are 2 recesses that hold them in place. The rubber tubes I have no idea what they are. Hence my assumption they were for shipping protection.

Pull a tire off and have someone apply the brakes. You should see them compress on the rotor and when the pedal is let off they should relax. Most times it is the piston that will wear and begin to stick, but not always. With the probable crud on your pins it may not be a good test now. I would pull one of them apart and see what has happened to the tubes. The pins go on bare.

You have a 2004 but no indication of what part of NA you are from. I live in a road salt environment and my calipers lasted about 9 years on the front. I had no problem with the rubber flex lines to the caliper until I had to replace the caliper. The lines were ok but the ends were totalled by the time I got them off with vice grips My ABS and Master are still good. I have a 2001 Sierra.

MikeInCtown · December 10, 2013

Seems to be a bit of confusion here. The rubber boots that were mentioned, corrugated, go between the caliper and the pad bracket protecting the exposed end of the pin. There are 2 recesses that hold them in place. The rubber tubes I have no idea what they are. Hence my assumption they were for shipping protection.

Pull a tire off and have someone apply the brakes. You should see them compress on the rotor and when the pedal is let off they should relax. Most times it is the piston that will wear and begin to stick, but not always. With the probable crud on your pins it may not be a good test now. I would pull one of them apart and see what has happened to the tubes. The pins go on bare.

You have a 2004 but no indication of what part of NA you are from. I live in a road salt environment and my calipers lasted about 9 years on the front. I had no problem with the rubber flex lines to the caliper until I had to replace the caliper. The lines were ok but the ends were totalled by the time I got them off with vice grips My ABS and Master are still good. I have a 2001 Sierra.

Agreed. The only rubber things that should have been used were the corrugated looking rubber boots. They are soft and pliable and go between the caliper and bracket to protect the surface of the bolt from corrosion so it will slide in the bracket. The pins should slide right into the caliper bracket with almost zero effort. Those two inch long rubber tubes were probably slid over the pins so that they would be protected from any corrosion or damage in shipping. If you pull the caliper and take the pads out, put the caliper back on, you should be able to slide it back and forth on the bracket with ease. That is a perfect test. If you cannot slide the pins easily in and out of the bracket, you have a problem with the bracket. This is a 10-15 minute job per wheel, so just do it asap. I don't think your hoses are the problem. It is that hard rubber tubing that you forced onto the pins.

MikeInCtown · December 10, 2013

By the way, brakes will stick if the pins have corroded inside the caliper bracket and do not slide freely. You most likely will notice this first on your rear brakes as the caliper bolts bolt into the slider pins. The slider pins must move freely in the bracket and there should be no tears or dry rot on the boots. The front is slightly different as the bolts screw into the caliper and only slide into the bracket. (with the rubber boot protecting the exposed surface)

PS, if you got bolts that require a torx T-25 or whatever size to remove them, get rid of them, and find the bolts that use a regular 6 point socket. You will find the work to be easier down the road when you don't strip out the torx socket hole on the pin. I have this issue and now when I replace my brakes, I take one pin out and have to rotate the caliper up and then off the bracket as the one pin is stripped out and I cannot loosen it. I suppose eventually I'll get a new caliper but it works perfect otherwise.

adamvf · December 11, 2013

Thank you very much for all of the relplies.

I thought putting the tubes on the slide pins was the weirdest thing ever. The truck hasn't been driven. I'll be jacking this sucker up tomorrow to remove those tubes and to give her an oil change.

Mikey, I'll get at that bracket test as well.

Bruce, I live in North East Florida. Just humidity and a little sea salt. Did the ends of your hoses just start corroding?

If the problem persists I'll look at replacing the flexible brake hoses.

I will update my progress. Thanks again.

1997SierraSLT · December 12, 2013

Every time I do a disc brake job I always pull those pins and lube the bores thoroughly with new high temp brake grease.

brucelimerick · December 12, 2013

That was lucky, the tubes shouldn't be melted.

My hose problem has been slowly happening over the years. Yes the ends were corroded and no wrench would fit or hold. My brake lines were totaled as well. I had half my truck apart this summer doing them.

The bracket test is good. One other thing to check is the metal plates the pads are bonded too. Sometimes the dies that punch them out are worn and there are burrs on them which prevent the pads from sliding on the chrome sliders properly. A little file work can make a big difference. Note I said a little. The pads should be snug on the sliders, not loose. If they are they vibrate and chatter, not good. It should take very firm finger pressure for them to slide. I just touch up the burrs, never open up the gap, they will be obvious.

Try to save the grease, I'm not sure if it is hi-temp or not. Some different types of greases don't mix well.

I agree with Mikey, I have had corroded pins before when the boot cracked or came off the recess. The bracket should slide smoothly and easily on the pins. The tubes are your problem. Calipers and flex hoses should go 100k miles easy even up here in the heavy salt.

adamvf · December 15, 2013

Well, oil change was successful. That's about all that I was pleased with.

I drove the truck around the block a few times to get everything warmed up and to purposely have the brakes stick so that I can do a test.

Brakes locked up after a while, I jacked it up, removed both tires and released the bleed screw on the passenger side. Fluid shot out as if someone had the brake pedal to the floor. There was a lot of pressure built up in the lines. I heard an odd noise on the other side of the truck, maybe the master cylinder. I was able to turn the rotor with my hand after that.

I removed the calipers and brackets. Three of the tubes shredded on the inside of the bracket. I had to yank them out with needle nose pleads. The other tube was still on the slide pin, I removed it.

Drove it again and it did the same thing. The brake pedal would get firmer as i drove around more. The brakes started sticking again.

Pressure again was building.

Is this problem now the flexible rubber hoses or something entirely different?

amc31b · December 16, 2013

Ugh, just take it to a mechanic man! No offense but you nor your uncle sound like you have enough knowledge or experience to be messing with brakes based on your postings here.

If you really insist on fixing this problem yourself, go buy the Haynes repair manual for your truck and throughly read through the caliper, rotor and brake pad replacement sections. Then go back and start completely over. It sounds to me like the "rubber tubes" you mention were either not installed in the right place or are the wrong parts for your truck.

If this problem is something as simple as you used the wrong parts or installed something incorrectly, a shop usually wont charge too much to do a basic brake job and fix whatever little mistakes you may have made. Being at fault in a serious accident because you butchered your brake job will cost you alot more.....

adamvf · December 16, 2013

I understand. Thanks

gmtech4 · December 17, 2013

Ugh, just take it to a mechanic man! No offense but you nor your uncle sound like you have enough knowledge or experience to be messing with brakes based on your postings here.

If you really insist on fixing this problem yourself, go buy the Haynes repair manual for your truck and throughly read through the caliper, rotor and brake pad replacement sections. Then go back and start completely over. It sounds to me like the "rubber tubes" you mention were either not installed in the right place or are the wrong parts for your truck.

If this problem is something as simple as you used the wrong parts or installed something incorrectly, a shop usually wont charge too much to do a basic brake job and fix whatever little mistakes you may have made. Being at fault in a serious accident because you butchered your brake job will cost you alot more.....

i was gonna say that but couldnt find a nice way like this ^^^^ lol

+1000

brucelimerick · December 25, 2013

Forget about the rubber flex lines. They have nothing to do with your problem. You have air in your lines. You have to re-bleed the system. Brake fluid does not compress nor build pressure. Bleed all your calipers not just the front.