Usually brake calipers are not repairable. It can fixed only temporary, and eventually you will have to replace it.
PS: the problem with steaky caliper is that it might lock at some moment, and there is not way how you can unlock it if you are not in your garage. You do not want one of caliper get locked somewhere on highway.
Sticky caliper.
How do you get the brake piston to retreat back in caliper ?
T-55
You will need special brake caliper tool such as a C-clamp to push back the piston on the caliper of a 2002 Mitsubishi Lancer.
Remove brake caliper and then caliper mounting frame . Rotor is now free.
18mm
Lift the vehicle, remove the tire, remove the brake shoe/caliper, and remove the old brake pad. Put in a new brake pad, replace the brake shoe/caliper, replace the tire, and lower the vehicle.
7mm
Yes. Brake caliper compression tool. Ratcheting calipers
Remove the tire and wheel from your 2002 Chevy Malibu. Remove the brake spring and the brake caliper. The brake shoes will come off. Reverse the process to install the new brake shoes.
Jack up the 2002 Optima and remove the wheel. disconnect the caliper brake line and drain into a bucket. Unbolt the caliper, and remove it with the pads. Bolt the new caliper on and replace the pads. The brakes may be spongy and the new caliper will require bleeding.
3/8"