Stuck cbrake caliper

I have 96 bucick century 50,000 miles. The calipers froze up on slide bolts and would not float causing the barkes to overheat.



Replaced rotors, calipers and shoes. The original passenger side caliper would depress all the way without openning bleeder value.



Shortly after replacing everything the pads where once again gone. In replacing the recent new pads the passenger caliper piston again would depress without openning bleeder value.



I am not sure what the problem is and where to go from here and am open for ideas.

All sliding parts must be lubricated periodically. Use a high temp “never sieze” type of lubricant. Use it sparingly. I forget the name of the stuff I’ve used for 30 years, sorry. Don’t get any on the rotors or pads.

Sounds like you brakes were not properly bled.

One thing I like to do when replacing disc brakes…is to remove the slide pins clean them up very good on my spinning wire wheel. Then when I put the brakes back in I use some good greese and lube them up well.

I know where this one is going and I hope I never have to journey down that long uphill path. I’m guessing that your rear brakes are just fine. Now we’re thinking rubber hoses which seem to be a common source of misery. If you find that the rear brakes have evaporated, you might consider something wrong with the vacuum booster. If there is; you might drive down the street and have somebody see if your brake lights are on. Nope, that won’t do it unless there is sonething funny with the brake pedal. Maybe it won’t retract all the way. Good luck. Once you solve this problem, you can tell me about brakes and I will listen. Maybe. I just thought about loose wheel bearings but I’m really guessing wildly now.

The rubber brake hoses have deteriorated, internally. You can’t see this deterioration externally. Change the brake hoses.

i am assuming front brakes, correct?

which brake pads wore out? one or both sides? the ones on the inside or the outside, or all of them? it sounds sort of funny if ALL of them wear out prematurely.

if they are ALL wearing out at the same time, then the brakes must be sticking on.

if this is the rear brakes does this car have separate brake pads for the E brake?

I hadn’t thought about the brake hoses breaking down on the inside but this could be the problem. I actually had that happen many moons ago when rebuilding a wheel clynder that I found pieces of rubber in it and I guess since I have never had it happen again it took a back space in the old gray matter… Thanks, will check them out.

I use a synthetic brake caliper grease from Permatex. It is blue in color, and widely available in many parts stores.

You want to check the brake hoses out for interior deterioration, right? That might be possible with a bore-scope; but, usually, not practical. You can tell if some interior pieces have broken off and are impeding the release of some of the trapped brake fluid pressure against the brake caliper piston(s) by: Loosening the caliper brake bleeder screw; have someone press the brake pedal while you observe the bleeder screw. Brake fluid should come out in a nice pee stream. If it doesn’t, there is a blockage. When the brake pedal is depressed, there are hundreds of psi brake fluid pressure against the brake caliper piston. When the brake pedal is released, there is nothing to push the brake fluid back toward the brake master cylinder; thus, a residual fluid pressure is left which will exert against the brake caliper piston, causing continued brake application.

When you say the caliper would depress without opening the bleeder valve, do you mean it could be pushed back with a c-clamp without opening the bleeder valve? The caliper that could not be depressed may be the problem. If you replaced both calipers there may be a problem elsewhere in the system.

It ended up being the antilock brake module. I did some research and found there is an ongoing problem with these units thru olds, chevy, buick, and all models that these units are used on. One or both of the front disc brakes will grab at any given time and not release dragging the brake. Or as these did just the other day they lock up and the car won’t move. The module alone was $280 remg. the assmy unit was $580 remg., an entire unit new was $860. I picked up the entire assy. (module, pump assmy., master cylinder, and reservoir) out of my freindly salvage yard for $100. This is the best way to go because taking the unit apart to just replace components means more work than just replacing the entire assmy. Two bolts, 4 lines and 4 plugs and the unit is changed also you need to bleed the brakes either way so changing just components doen’t save you any time.

On these models you need to use a Vac pump to bleed the pumps then you can bleed the wheels themselves just like you would a conventonal system. Many of the new models you have to bleed the master cylinder, then bleed the pumps then use the pumps themselves to purge the system and or on some of the high end new ones you have to have the secert squirrel codes to enter into the code readers to get the pumps to run so you can purge the system.

Hope this helps

Glad you came back with the solution you found. Now, if someone can come up with a diagnostic, for the average home mechanic, for sticking/jamming brakes caused by a malfunctioning abs system, it could be quite useful.
I have to wonder how long the salvage abs will last.