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-   -   05 chevy malibu, brake not releasing (http://www.diychatroom.com/f46/05-chevy-malibu-brake-not-releasing-120321/)

4just1don 10-16-2011 07:37 PM

05 chevy malibu, brake not releasing
 
front passenger side brake got very hot and doesnt release right. What forces them to release.? how do you fix it? new calipur or is their a repair for it?

Doc Holliday 10-16-2011 08:01 PM

I'm no expert (although I did work at Brake Check for some years and do all my own brakes) but usually it's the lack of pressure that releases the brakes. The piston pushes into the disc and the other side is simply pulled into it when you hit the pedal. You may just need to clean some dirt out or you may need a new caliper.

rusty baker 10-16-2011 08:45 PM

Doc is right. The only other thing I can think of, if it's been sitting, rust can make it stick.

DrHicks 10-16-2011 11:08 PM

Quote:

Originally Posted by 4just1don (Post 750047)
front passenger side brake got very hot and doesnt release right. What forces them to release.? how do you fix it? new calipur or is their a repair for it?

Your brake pads literally ride on the rotor at all times. They don't so much "release" as just release the pressure.

If your brake got hot, and now doesn't release right, you should probably just replace the caliper. There are repair kits, but they don't amount to much. And the kit probably wouldn't fix the problem anyway.

Replacement calipers are pretty cheap, and this should not be a hard job to do. The only thing that might complicate it is a rusty brake-line connection, so soak it down good with PB Blaster.

47_47 10-17-2011 03:51 PM

Disc brakes use a square seal between the caliper and the piston. The square seal is distorted when the brakes are applied and want to return to the straight position when the brakes are released.

Check the pads and caliper sliders, The must move freely for the brakes to release properly. If ok, the other causes are the caliper, brake hose or proportioning valve.

Thurman 10-17-2011 09:55 PM

"front passenger side brake got very hot" You just solved your problem with this statement. First: Why did the "brake" get very hot, or better yet: What got hot, the rotor, or the caliper, or both? Something caused the piston in the caliper to stay extended and the pads kept rubbing the rotor getting everything to heat up. Two things here: When the caliper gets hot, the brake fluid (if factory type DOT 3) will boil causing the brake fluid to chemically change and actually turn to a syrup like consistency. AND-when the caliper gets hot, the "goo" in the caliper, which caused the piston to not pull back, gets even worse. At times so thick the piston cannot be removed for a re-build. IMO: In this case I would obtain two (2) rebuilt caliper units from a parts house, also new pads for both front wheels, have the rotors turned. Basically a front end brake job. Buy some DOT 5 brake fluid, bleed ALL the brakes until this new fluid comes out ALL brake bleeding fittings and I'll bet you will have some really nice brakes.

SALEEN961 10-18-2011 01:02 AM

There is no need for DOT5 brake fluid on an otherwise stock 05 Chevy Malibu. He would need to flush all of his brake lines to use DOT5 since silicone based DOT5 fluid is not compatible with glycol-based DOT3 or DOT4 fluid, and a complete flush requires system disassembly to remove fluid from low-lying areas. Personally I would never make the switch because it's simply not needed for a typical street driven car.

I've had smoke wafting out of my wheel wells and I've gotten my wheels too hot to touch, but I've never had any pedal fade from boiling the fluid even when using standard Prestone DOT3, although I do normally use Valvoline DOT3/4 brake fluid because the cost difference is insignificant and it's a better fluid. The only vehicles that need DOT5 are either highly modified or came form the factory with it.

4just1don, considering the age of your vehicle, first I'd pull off your caliper and make sure that the caliper slides move freely, if they do then try to compress the caliper piston to see if it also moves freely, if it does then bleed that caliper to see what the condition of the fluid is, if it is in good condition the next thing I would check is the brake line itself, sometimes they can become damaged during a brake service and a little flap of rubber in the line will act as a check valve either keeping the brakes from applying or releasing. Blowing air through the line like a straw is an easy way to tell if that's what's happening.

rustyjames 10-18-2011 04:22 PM

^^ Agreed, I've seen many instances where people had a full bore brake job done and it wound up being a bad hose.

polarzak 10-19-2011 06:47 AM

Quote:

Originally Posted by 4just1don (Post 750047)
front passenger side brake got very hot and doesnt release right. What forces them to release.? how do you fix it? new calipur or is their a repair for it?

Had this happened to my car recently. It turned out the be a stuck caliper piston. Replaced the caliper and all was good.
See if you can press the piston back into the bore with a C Clamp. If it goes in relatively easily, then it is some other problem like a brake hose, or stuck sliders. If the piston is seized, then you need a new (or rebuilt) caliper (not two as was suggested). Once you determine what the cause was, check the rotor; it may be damaged from the binding and heat. If it is, then it should be resurfaced. Here I would suggest you do both sides (or buy new ones) and install new pads.

PJP 10-22-2011 11:02 PM

take the wheel off remove caliper from hanger leave brake hose attached open bleeder push piston in if it goes right in replace brake hose if not replace caliper hose calapse inside and dont let the pressure release


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