Maybe my calipers are siezed or something else?

At about 50K I had some service done and the mechanic said that my brake pads were getting thin. So I ordered some Hawk HPS(front & rear) from FredBeans and slapped them on. The existing rotors were grooved but, because my son was only a month old I was too tired to swap/wait for new rotors. At that time I noticed the passenger rear rotor didn't look like it was getting any wear. There were/are rust spots on the disc surface. It's been about 3000 miles and the driver's front is now making a light grinding noise when rolling(off brake), I can smell burnt pad, and there's light smoke after I've stopped. I removed the tire and the backside of the disc looked too thin so I ordered new pads and new rotors(all around). Now I'm worried that those calipers are siezed. Is there a way to test if a caliper is siezed? Is it just a coincidence that the calipers are failing in reverse order of how the brakes should be bled? Maybe there's air in the line? Help.

Get an IR thermometer, drive around the block for a few minutes, then hop out and check the temps of the rotors - side to side they should be similar, if you have a seized caliper the temp will be way higher.

I gotta buy a laser thermometer? I'd like a reason/excuse to buy another tool but, is that the only way to check for a frozen/siezed caliper?

you should be able to compress the caliper piston by hand with a c-clamp and easily slide the caliper mount slides. if not, you have a siezed caliper.

The other way, not nearly as accurate as Rao's, is to literally put your hand near the rotor after driving a few blocks and compare heat side to side.

 

I've seen one frozen caliper heat up the wheel so much (after a long drive) that the entire rotor/hub assembly was radiating heat from several feet away...i.e. getting close to the wheel was actually very, very uncomfortable.

I *just* finished replacing all of the rotors and pads. I used Centric rotors and Posi-Quiet pads. I bled the brake lines. Who's the genius that put the rear bracket bolts in a place where you gotta use 8" socket extensions? I put the tires back on and I drove local roads across town.

Now I'm getting a vibration through the gas pedal while moving. It's not very noticable at low speeds but like my sonic toothbrush at 40mph. Since I didn't do anything to the tires, I don't think they are causing this. Is it because I didn't "bed in" the pads?

Are you actually braking or just resting your foot on the pedal and you feel vibrations?

 

I'm not familiar with Posi-Quiet, but Bendix used to put a very gnarly surface on their brake pads to help them bed almost immediately. It would cause some pedal vibrations for the initial miles as the pads smoothed out.

 

Any chance you installed something incorrectly with how the piston sits against the pad (I.e. Shim or without?) or left something loose?

 

Joe

Joe,

 

No pressure on the brake or the gas pedal and I can feel vibrations. Like when I drive over a metal grated bridge but, lighter.

 

I used brake goop against the pad back, shim, and then caliper grease.

 

There's always a chance I installed something incorrectly.

Probably nothing loose though.

 

*Full Disclosure*: I was scraping the rust off the rear brakets and I lost track of which was left or right. I installed them both on the same side (no, not at the same time!) and they looked identical so I just picked one. Culprit?

Well, your pad should not be hitting your rotor if you are feeling vibrations that build with speed.

 

Unless you've got a sticking caliper. Did you remove, clean, and grease the slide pins?

 

At this point, I'm guessing that you've got a sticking caliper and that by changing the pads you moved the position it typically rests in, and now it's causing a problem.

 

Either that or, again, you did something incorrectly with rotor installation (that's pretty hard to do) or pad installation (easier to do).

 

Cause if you left the tires alone, and everything is tight (check that, including lug nuts), then there's not much else that you changed that's rotating and could be causing a problem.

if you have a stuck caliper, all you gotta do is take the pistons out and clean them. take the caliper off, use some compressed air to push the pistons out. you can get a boot and seal kit to rebuild the caliper or if you're cafeful by not ripping the boot, you should be okay to use them again. a stuck caliper is not because of bad seals, etc, but because of the piston rusting. you just got to clean the rust off. i did so with a drill disc attachment with a scotchbrite-like material. clean it off really well without scratching or gouging the piston.

 

the calipers started getting stuck one by one after i did new pads and rotors for my dads old forester. i only replaced the seals for one caliper that was leaking. the others i just reused the seals/boot, after 10k miles still working good.

Wonder if the ABS sensor is messed up. You did say lots of break dust.

The car feels fine after it's been sitting a while. After I drive around for a bit I start to feel the vibes. I drove to work this morning and only half way I started to feel the vibrations. When I parked, I held my hand near all of the wheels. The driver side front was warmer than the rest. So I'm thinking something's up with that one.

I checked all of the slide pins when I removed the brackets - they were fine - sliding very easy. The pistons on that one(Front-LeftHand) pushed in fine with a C-clamp when installing the pads. So confused.

 

LongHiway: I've driven about 50miles so far on the new pads. I don't see much brake dust.

The car feels fine after it's been sitting a while. After I drive around for a bit I start to feel the vibes. I drove to work this morning and only half way I started to feel the vibrations. When I parked, I held my hand near all of the wheels. The driver side front was warmer than the rest. So I'm thinking something's up with that one.

I checked all of the slide pins when I removed the brackets - they were fine - sliding very easy. The piston on that one(Front-LeftHand) pushed in fine with a C-clamp when installing the pads. So confused.

 

LongHiway: I've driven about 50miles so far on the new pads. I don't see much brake dust.

 

I just had to replace both my front calipers. I would get a vibration in the wheel at different speeds then it would go away after a while. Then come back again all without braking. It finally got worse, to the point of after a year of trying to find out where the shimmy was coming from my right front was totally gone. & my left front had 1 piston in trouble. Both were replaced with only 63000 miles on the car, also had to replace the rotors & pads due to warping.

Kevin,

 

You got me spooked! I don't want to wreck a brand new set of pads and rotors!

I just took off a set of Hawks w/ < 1000 miles on them. (sound of $ flushing)

Wondering if I should replace the caliper now?

ahhhhh!

no need to replace the caliper really. just clean it or rebuild it like i said. saves big money.

At about 50K I had some service done and the mechanic said that my brake pads were getting thin. So I ordered some Hawk HPS(front & rear) from FredBeans and slapped them on. The existing rotors were grooved but, because my son was only a month old I was too tired to swap/wait for new rotors. At that time I noticed the passenger rear rotor didn't look like it was getting any wear. There were/are rust spots on the disc surface. It's been about 3000 miles and the driver's front is now making a light grinding noise when rolling(off brake), I can smell burnt pad, and there's light smoke after I've stopped. I removed the tire and the backside of the disc looked too thin so I ordered new pads and new rotors(all around). Now I'm worried that those calipers are siezed. Is there a way to test if a caliper is siezed? Is it just a coincidence that the calipers are failing in reverse order of how the brakes should be bled? Maybe there's air in the line? Help.

 

Caliper piston for sure. And note that they don't always seize, they are sticky. That means sometimes they stick, and sometimes they don't. They can stick in, or they can stick out. Sometimes all it takes is a good bump in the road to free them up.

Is there a way to clean and rebuild using hand tools? Would I be able to move the piston out without a compressor?

Is there a way to clean and rebuild using hand tools? Would I be able to move the piston out without a compressor?

 

Soak the piston/caliper in oil and have a shop blow the piston out with compressed air. Hone the bore, replace piston.

Thanks for the tip Robin but, I've never had luck taking something to the local garage. They either won't touch it or want to charge me $50.

 

So I ordered 2 rebuilt calipers(front L&R) from RockAuto. I read somewhere that it's best to change them in pairs. I got the Nastra ones since the customer rep said they were basically the same as the other rebuilt ones. 2 things to note when I replaced them:

 

1) The bleeder value had little bits of cardboard in it from the box it came in. The whole thing was wrapped in shrinkwrap plastic but, the valves from both had pushed through the plastic and was sticking out the box! I took a vacuum and needle and sucked out all of the bits.

 

2) The OEM bolts holding the caliper to the bracket are 14mm. One of the calipers came with 12mm bolts. *I'm not sure of the sizes but there definitely was a 2mm difference. I kept the originals and sending the smaller ones back with the core.

 

I drove to work and the vibration seems gone. YAY!

I called RockAuto to get the details of the core return and ask about the extra washers that were sent to me. Turns out they were crush washers that were supposed to go on the bolt for the brake line. The OEM didn't have these washers (far as I can tell). It also has not leaked in 24 hours. Can someone verify whether the OEM brake line has crush washers for the bolt between the brake line and the caliper body? Do I gotta get under this car and bleed these things again?! AhhhH!

It DEFINITELY has washers on BOTH sides of the banjo bolts - all banjo bolts are set up t his way.

I was hoping you weren't going to say that Rao.

OK, 2 crush washers on each side, bleed 'em, and done!

 

Rao, you'll appreciate this. Because I could only get help early in the morning I had my car up on jacks overnight. I think I reduced wear on my suspension and tires.

Good call I never understood people who actually left their cars parked on the tires

Good job Bman!