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Driver-Rear Caliper Piston not retracting

Exile

Exile

New member
Looking for some help/suggestions on this. I just replaced all the calipers on my 2001 GP GTP. All the pistons were rusted and not applying even pressure (causing very uneven pad wear), and that's not good for a spirited driver like me. I also got all the rotors cut and got new platinum/gold pads from Advanced. I've only driven about 20miles with the new brakes, but so far the fronts and passenger-rear are working good.
The Driver-rear however is giving me a lot of issues. It is not retracting fully after the brakes are applied. I have already super-heated the rotor to the point of smoking during my first drive of ~10 miles. The calipers are all Re-manufactured, so I thought I just got a bad one. But the problem persists after I exchanged it for another caliper.
I followed all torque specs for the caliper bolts/brackets/hoses. I bled the new caliper like crazy. Used proper lubrication on the floating caliper bolts and on the pad clips. I did the recommended 20/30/30 procedure for breaking in the new pads. I plan to replace the rubber hose, I REALLY hope that does it. I've read they can collapse internally and form a check-valve of shorts. If that doesn't do it, I suppose I have to look towards the steel lines for the issue.
I'm guessing my previous brake wasn't doing much of anything in the driver-rear. Which is interesting, I would think it would cause ABS lights to come on.:th_scratchhead: But this is just speculation.

Any other suggestions on what could be worn out / need to be replaced in order to fix this? Car has been on jacks for days, really getting annoyed :mad:.

Thank you !
 


when bleeding that caliper does the fluid come out with force like the rest of them?


what year is your car? if its a 04 plus the e brake maybe to tight and making the caliper drag the rotor.
 
Scottydoggs said:
when bleeding that caliper does the fluid come out with force like the rest of them?


what year is your car? if its a 04 plus the e brake maybe to tight and making the caliper drag the rotor.
Click to expand...

Yea it bleeds just as well as the others. Its NOT trickling / struggling by any means.
My car is 2001. I've adjusted the inner parking brake shoe to it's narrowest setting, dont' think it is that.

I should add I changed the driver-rear wheel bearing about two months ago as well due the original one getting sloppy. This newer bearing has a little more resistance than the passenger-rear, which is original (to my knowledge). I can't imagine why a wheel bearing would affect the function of the brake caliper/pads, but perhaps I am missing something? Or this is an insignificant bit.
 
seems odd being its doing it with a 3 rd caliper really. something up stream bust be not right. if your gonna change the line may as well swap to stainless steel lines.
 
I plan to do SS lines at somepoint, but not now. Just spent a bunch on these new calipers/pads. I just need the car done and out of the garage already !

Any other suggestions?
 


02NavyBlue said:
Wait, so did you replace the brake hose going to that caliper yet?
Click to expand...
No I have not. Just bought the hose actually, will give it a try tomorrow. But I am doubtful, unfortunately, that this will solve the problem. At which point I will be out of ideas as to what's wrong....

I will update after I install the hose.
 
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I've seen people replace a brake hose before the caliper when the brakes stay applied, so it must be somewhat possible.
 
02NavyBlue said:
I've seen people replace a brake hose before the caliper when the brakes stay applied, so it must be somewhat possible.
Click to expand...
I installed the hose today. It definitely improved the function of the caliper, almost positive it isn't sticking anymore. The old hose was partially responsible. Took it for a brief drive around town, prolly ~5 miles. The driver-rear rotor is still experiencing a lot more heat compared to the rest of the wheels. And the wheel still does not turn as smoothly or easily as the pass-rear (otherside). There's a night and day difference.

I believe the $55 wheel bearing I installed two months ago is the culprit now. I have requested a replacement but it will prolly be at least a week.
Tomorrow during the day I am going to take it for a longer driver and see just how badly its going to overheat. Waiting for daylight to see the smoke again, lol.

New pads + new rotor + new caliper + partially defective wheel bearing = my problem?
Any other ideas? Is my assumption about the wheel bearing the possible cause, anyone???:th_scratchhead:
 
I actually did that, coincidentally, when I took off the first caliper I bought to go exchange it. It made a small difference, which probably came from the lack of the pads touching the rotor at all (i took them out of the bracket). There was still a huge difference compared to the other side (pass-rear).
I also at that time took the rotor off and took a wirebrush/file and knocked off any rust on the Parking brake backing plate. The rotor barely makes contact with it but I did it anyways. Adjusted the parking brake shoe to it's inner most setting too. The pads have zero use on them, cause I don't use the parking brake. I don't see how it would be rubbing the brand new, not-rusty rotor.
 


Did about 25 miles of driving today. The driver-rear brake/caliper is working perfectly now I believe...its certainly not seizing anymore with the new hose & caliper, woot. :th_thumb-up:
That wheel is still getting much hotter than the others after ~15miles of continuous driving. I'm trying to track down a infrared temp gun so I can see how hot it's actually getting and if the rotor/hub is approaching any short of danger zone. Especially if I were to drive it to school which is 30miles at highway speeds. Did some research, apparently it very rare for a wheel bearing to fail in this way but in some instances they've gotten so hot they actually melt the entire aluminum knuckle and fuse a bunch of stuff together :th_crossbones1:.... hence me tracking down a infrared. But the ENTIRE wheel/rim after the 15 mile drive was warm to touch, and its about 22 degrees out here in Chicago atm. The front wheels were half as warm, and those brakes are doing 90% of the work.

Going to have my mechanic/family friend give me his opinion on the resistant wheel bearing tomorrow and check my brake work, I will update here on what he says.
At least I can drive it short distances now.
 
For the sake of closure...
It was the bracket that was the problem. Wasn't letting the caliper move freely causing the pads to rub.
Wish I had replaced it from the start, didn't think a chunk of iron could go bad. Guess it was warped...ever so slightly

note: the hose was the cause of the piston not retracting, the bracket was another issue compounded with that.
 
Did the pin not slide well in the bracket? You'll know right away when inserting it when putting the caliper back on.. They also get rust on the surface where the shims go, we sandblast that area at work to make sure the pads don't bind anymore. That's the other common issue. Warping? I haven't seen that yet.
 
The pins would go in without much fuss at all. Yea I wire brushed the hell out of the area where the shims go, was clean as I could get it. I don't get what was wrong with my original other than its, well, old. Warped just a lil bit is my only guess. But issue resolved after new bracket installed.. finally... after much frustration :th_angry-cussing:
 
Well that's good to hear (unfortunately after replacing literally everything else). Someone must have dropped it on the ground or something. Or threw it off a building, or ran it over
 


Lol something like that. Next project is to paint my calipers. Because my *new* ones had zero protective coating on them and look like junkyard calipers now. That really fresh bright orange rust is a real eye catcher, literally.
Prolly just gonna pick up all new brackets for the rest and prepaint them. They're only ~$16 on amazon and would save me the prep work. And another potential headache.
 
Yeah many claim to have a rust resistant finish, haha that's bs.

I painted mine and a few areas already have spots of rust (on the back which is good) My regrets are I should have prepped better (I prepped pretty good, but I needed more than a lot of wire brushing apparently) Something like a angle die grinder with a scotch brite to get it to bare bright looking steel. I had no rust but that wasnt good enough. Also I did 4 light-to-medium coats but should have done around 7 which seems a lot but is appropriate. Or maybe the paint I used wasn't the best (I used dupli-color caliper paint). Even the rotors have a bit of rust and they were spotless before. I did 4 coats there as well. I will repaint them and use more coats when I do my brakes.
 
They were completely orange within five days. I've had a couple people point them out to me actually, cause they're so radiant lol.
Good info there tho. Although it makes me really wish I had painted them right when I took them out of the box, now I have a lot of prep work. Should be pretty superficial rust tho right? I wonder if CLR would knock off most of it.
 
Yeah it's all surface rust then. Try to really get down to bare metal. My rear calipers were a joke with how rusty they were, it was crazy. So much came off when I wire wheeled it. I had to paint them, the torque stars show the entire caliper.

Here was what mine looked before and after prep. Has rust on them now though..
Before
68c3.jpg


After prep. Next time I will use a angle die grinder on it to really get down to a better finish. The wire brush made it really glossy. No rust paint or anything like that, just too smooth. Sandblasting would be the best I think, maybe I can use the one at my work.
v992.jpg
 
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