Question About Brake Pad Replacement?

Question

I am in the process of replacing my brake pads but my caliper piston is seized and will not compress. I have only tried using a c clamp. Is there anything else I can do to either compress it or get it out so I can clean it?

Answer 1

front brake calipers push in with a c-clamp, rear brake calipers twist in, if you can't get them to move you need new calipers.

Answer 2

I have never replaced a caliper. Usually all you have to do is clean it with brake cleaner and lube the piston with clean brake fluid before compressing it. I always use a large C clamp for the compression. It is HUGE though. On the rare occasions that hasn't worked, you can get the piston out with compressed air and inspect the caliper bore to see if it is all corroded. If it isn't, you can just rebuild the caliper by honing the bore and replacing the seal. It is very easy and much cheaper than replacing the whole caliper.

Just be sure you clean it up before you compress it or you will wreck the seal and then you really will be in a dangerous situation. If you aren't good with tools, brakes are really best left to a professional shop though.

ALWAYS check out a manual first! Some cars have very specific ways of doing things that 100 percent matter! There  may be a reason you can't just compress the piston with a clamp.

Answer 3

Replace the caliper.  That is the only safe way otherwise you could have hydraulic failure or worse.

Answer 4

If it's most kinds of rear disc brakes, you need to rotate the piston. If not, or if you broke it by doing it the wrong way, you'll need a new caliper.

As usual, you could get a lot better advice if you included your car's Year, Make, Model, and in many cases, Engine size.

Answer 5

You might try opening the bleeder,that will release the hydralic pressure on the piston,use a good size C-clamp with the old brake pad in place so your piston will go in evenly straight,not on a bind. If that doesn't work I would suggest a remanufactured caliper,they're really not that expensive. I do hope we are talking about front brakes,as rear disc are usually different,then you need a tool to turn the caliper piston in clockwise,it is always easier with the bleeder open,at the very least,make sure your resevoir cap is off to allow the fluid to back up.

Answer 6

Replace the caliper, even if you do manage to compress the cylinder after the first time you press the brake pedal in, it won't release the way it should and the pads will wear more quickly.