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Discussion Starter #1
Ok guys, here's another one. I had to change out my rear brake pads because it wasn't passing state inspection. I was very surprise as I put them on the same time as my front brake pads (Hawks HPS). When I went to take them out, I noticed that the calipers didn't slide out but had to be pushed off with some good amount of force. When I examined my pads, the drive rear was down to about 4mm while the passenger rear was down to about 2mm. I'm completely surprised. I checked out my front pads and they have plenty of life on it (didn't take it off to measure but definitely visible). I've only had the pads on for about 10k miles too. I have a feeling that the rear calipers were stuck or didn't have much movement at all.

What could be the cause of this? Air in the system? Caliper going bad? When I depress down on my brake pedal, it feels a bit spongy but it still stops me on easily if I need to. How can I go about diagnosing this, besides taking it to a shop?
 

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Just take a file to the slide points, and also buy a hardware kit with new tabs where the sliding takes place. Those, combined with brake hardware lube and you'll be fine.
 
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Discussion Starter #5
whoa, thanks for replying but you got me at caliper, then lost me. =D

My knowledge of the braking system is...umm close to minimal except for knowing how to change the pads and bleeding the fluids. Ok, going to do some reading...

Ok, just read up what a seized caliper is. I can imagine that a seized caliper would cause the accelerated wear, however I never saw, smelled, heard, or felt anything funny with the rear brakes. On second thought, there were a few times in which I heard what sounds like something dragging on metal when slowing down (this was with the windows down).

Wow, rebuilding the caliper seems a bit time consuming. With a baby coming ...umm any day now...I won't have time to work on it for a while. Might have to look for a used caliper then.

I do remember when I installed the rear brake pads, I applied a nice and even amount of brake quiet to the pads. Could that material have gotten into or around the piston and seized it? Thanks for the inputs fellows.
 

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I'd bet things are simply rusty and causing the drag.

I would think the odds of your piston actually being seized is pretty damned low. If the car had been setting unused for 12 years, maybe. My brother has an '88 Buick with about 16k miles and lives in the garage. Last summer he took the braking system apart. Both front calipers were full of rusty fluid, and naturally the seals hadn't seen regular use either. Neither piston was seized.

As for the guide pins, I've only seen one that ever needed replaced; it was broken. Just clean the old ones with a ScotchBrite pad or emery cloth, re-lube them and reinstall.

As for hardware (tab) kids, Rock auto has them for dirt cheap. When I saw that ours uses those pseudo-chrome plated tabs, I ordered new ones before doing my brakes. Those things are always rusted. I used the new tabs, wire-brushed and/or filed anywhere the metal meets or comes close to meeting- then used brake lube on any contact/movement point.
 

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I'm about to rip one of my right rear caliper out this afternoon on my MS6. I changed the pads at about 40,000 miles when wear was extremely uneven with pass. side worn down to metal.
Since the dealership had pointed the need for rear pads out to me, I asked why would the rear pads be wearing so fast if there was not a problem with the calipers. "Oh no problems just worn pads" The front pads had at least 50% of life left on them!

When I changed the rear pads the calipers were not seized, so I really paid attention to changing the tabs and cleaning the pins.

It didn't seem to work I heard the tabs hitting last week. Then the right rear stunk after a long drive on top of making noise. I bought a rebuilt caliper from Autozone which should finally resolve the issue. ( I didn't want to spend time rebuilding the caliper myself)

This seems to be a common problem with these cars.
 

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Discussion Starter #8
Thanks for the inputs. I'll see how my rear pads wear and check them in another few months. My commute to and from work is only 15 miles so I won't likely see much of a difference until a few months down.
 

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just recently was doing brakes and one of the calipers would basically lock up after installation. It had to much grease in the bores and was hydro-locking. Brake cleaner + cotton swabs did the trick. Get rid off all the grease from the bores and pins, clean them out with brake cleaner and relube them using little grease and see if that helps.
 

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My friend and me, both with a 2006 hatch 6i, we also have issues with my rear left caliper. I had to replace rear pads because of uneven wear. After pushing the car hard on the highway and jump on brakes in exits, the rear wheel is too hot to keep fingers on it and you can feel thousands watts of heat coming out from there. So I replaced the pads (45000Km, with EBC Greenstuff), lube everything and ensure all parts are sliding well. The bug came back in less than 5000Km, stick and overheat after a highly spirited driving and brakes are now dead after another 30 000Km because of this wheel, other are still ok.

I serviced them a month ago to put back an old original pad as a spare, inner pad, rear left was chewing the disc metal to metal, no more material. I found that pads are too stiff into rails, they don't slide well anymore with any bit of rust. Cleaned everything with a file, antiseaze applied everywhere and looks ok until I receive my new pads.

oem disc front, Brembo disc rear, EBC Greenstuff pads all around (I love them!). Oil has been reoplaced too, ATE superblue.
 

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Do you use your parking brake? If so, are you sure it's fully releasing?
 

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Do you use your parking brake? If so, are you sure it's fully releasing?
I have a man. trans. so yes, everyday. My brain is used to, its automatic, I can't forget.
As a side note, I never got this problem after playing with the handbrake to drift in snow. It really happens after hard cornering braking.
 

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At 80k miles I've had to replace both front calipers. Not too expensive to do and fairly easy.

This is what mine look like after some driving around town.

 

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At 80k miles I've had to replace both front calipers. Not too expensive to do and fairly easy.

This is what mine look like after some driving around town.

YouTube - Stuck caliper! ....damn it

My front driver caliper did that, and it was just that my guide pin was all fucked up. The rubber boot for it at cracked and let all the grease out, which ruined the chrome coating on the guide pin making it rough and eventually stick. I replaced the guide pins and rubber boots, re-lubed and I was good to go. I was toying with the idea that Karl said and just sand it smoothe and re-lube, but the part was inexpensive enough that I just figured I'd do it the "right" way and replace the part (~$20 IIRC).
 

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I was going to suggest if The slider pins don't come out as part of taking the caliper off, the slider pins usually have an Allen head and can be replaced. High temp grease like redline CV2 or Valvoline SynPower should be good and avoid separation. Most guys in the spec Miata community repack their wheel bearings with either of those. Had a slider pin seize to the brake caliper. Wound up replacing the caliper and mounting bracket.
 
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