I have had exacly the same issue, the mechanic replaced the brake pads, calipers, hoses/brake lines, then after all that and it still happening, he replaced the brake master cylinder and all was well, except for my wallet !!!!
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There are at least 2 items that will cause your problem. The first is when you changed the pads you place the caliper in a different place on the support pins that the caliper slides on to centralise the brakes on the rotor. These mounting pins are prone to rusting up and actually keeps one pad on the rotor as the caliper cannot centralise during brake application. The second is a problem that occurs when the brake fluid is pushed back into the master cylinder reservoir from pushing the piston back into the caliper. Muck in the lines is pushed back into the compensating ports in the Master cylinder causing the brakes to drag and build up pressure from the heat generated by having the brakes on. Try flushing out the brake system using metholated spirits or replace the master cylinder
I had the same problem and replaced both calipers with no change, I figured it was the master cylinder. When I pulled off the master cylinder I saw the vacume booster had about 2 cups of brake fluid in it which leaked from the front of the master cylinder. I replaced master cylinder and vacume booster and brakes work great now.
Check for leaks around brake calipers or cylinders, check for leaks around brake master cylinder, may be leaking from master cylinder into brake booster, remove vacume line from booster and see if you can detect oil inside, if your adding oil to brakes every three to four days a leak should be easy to find.
They are rather easy to replace, disconnect the brake hose, and remove the caliper as you did replacing the pads. You'll need to then bleed the caliper until clear fluid, with no air bubbles come from the bleeder screw. Check that you don't have a collapsed brake hose, not letting the fluid return to the master cylinder.
By "sticking" I am assuming that you mean that the brakes are staying applied (calipers are not releasing)and burning the brake pads and rotors up.
The most common cause of this is brake hoses.
The hoses that connect your calipers to the steel brake lines have an inner lining and a reinforced outer "shell". sometimes the inner lining tears loose from the outer shell inside the hose. (It cannot be seen by "looking" at the hose.) The inner lining then starts to act similar to a "heart valve" where it allows fluid to be pushed down into the caliper, then collapses inside the hose, blocking the fluid from returning to the master cylinder when the pedal is released. This can happen just because of the age of the hose, but is more commonly caused by someone allowing the caliper to hang by the hose while replacing the brake pads without using anything to support the weight of the caliper.
To diagnose this condition, raise and support the vehicle and remove the wheels. Make sure that the transmission is in "Park" (Automatic Transmission) or "Neutral" (Manual Transmission) and apply the parking brake. Then start the engine and apply the service brake. (Press HARD on the pedal) Shut the engine off, release the service brake and open the bleeder screws on the calipers. If brake fluid squirts out of the bleeder screw under pressure, then the hoses are the cause of the calipers not releasing.
Ok Have you recently replaced the pads? Do they act normal after they cool down? Are the pads in good condition, pads that are so worn that the caliper pistons come out beond their normal limit may stick there due to excessively worn pads. If so make sure they are at least factory grade quality Good are bendix, the only thing that can cause your symptoms is a bad master cylinder because it affects BOTH front calipers equally if it was a caliper it is likely to affect only ONE. Let me ask you this happens after driving in heavy traffic or after along drive?
If So there have been countless cases of boiling brake fluid, Old Brake Fluid gathers moisture and its boiling point is lowered, Fluch out ALL the old brake fluid and have new put it.
also is there any chance even the slightest chance that something other than brake fluid even a drop or two is enough to do damage. has been added to the master cylinder at any time? If so you need to replace EVERY PART IN THE BRAKE SYSTEM INCLUDING THE ABS CONTROLLER THAT HAS ANY RUBBER PIECES IN IT CALIPERS HOSES WHEEL CYLINDERS,MASTER CYLINDER just for your information.
I believe you have a bad master cylinder but do not buy a rebuilt one only bran new and preferably from the dealer.
Please contact me if you need more help and would you give me a good rating if you feel my information is helpful.
Thank you ,Randy