parkale1

Hi,

I was changing out my brake pads and on the passenger side rear caliper, the caliper piston will absolutely not compress enough for me to install my new brake pads! I am pretty annoyed that no matter how hard i turn and press the piston in at the same time, it will not go. I even tried just turning the piston and just compressing it. After fiddling around with the piston, i can't even re-install my old brake pads. This is seriously ridiculous. I even left the bleed screw open to see if that would help, opened my brake fluid cap in the engine bay, even pumped the brakes to see if that would help. When i pumped the brakes, the caliper piston almost ended up popping out if the boot wasn't holding it in. I even looked inside the caliper piston and it seemed that nothing was out of place and the thread wasn't stripped or anything!

Does anyone have ANY idea what is going on? I am stumped, i feel like i tried almost every option and still no results!

j_fitz7

they get stuck, search the archive, i believe you pull the piston out, clean up, and maybe have to get a new seal to fix.

im about to do rear pads as well and i fear a similar fate.

RolledMySTi

Your caliper is seized. Unfortunately this is a common problem. You will have to get another caliper or take that one off and rebuild it.

CTAudiDriver

Yea, try looking for this... othewise when I did mine one of the rear calipers was the same way, I had to use a leverage bar on the tool and just about all my strength to get it to go in but it still works fine now that I have it installed.

nimmote

I just re-built my rears a month ago. My boots were torn, so i got a kit from ECS tuning that had 2 new boots and 2 new inner seals. When i was trying to put them back together i had a hell of a time. With the inner seal out, they went together very easily, but with the seal in, i had to have one person holding down the caliper on the bench and one person with a large c-clamp with a 18" breaker bar to get it going. And that was with lubing the whole thing up with brake fluid. Make sure you have it lined up correctly and i would do it on a bench or something. Without the special rear brake tool, it can be done, but good luck. And even with the tool, it would still take lots of force. The cylinder is tricky, it doesnt have to spin to come out, but it does have to spin to go in.

So if you have it that far apart and have time, i would get the rebuild kit from ECS ($39 for whole rear) to be safe. If you or anyone else does get the kit, GET THE EXPENSIVE ONE! The $39 kit is for both sides and fits. All the $19 kits are the wrong size. I ordered like 5 kits from other companies including ECS before i got the right one.

Anyway, good luck!

parkale1

argh i finally found out what was wrong! The way you mentioned nimmote was how i was doing it and i was about to give up until today my dad and i found this part of the tool that wedges the piston tool inside the caliper, using that leverage we were able to EASILY push the piston back in. I feel like an idiot for missing it yesterday and not being able to use my car today because of it, but man am i happy that i didn't buy a whole new rear caliper assembly! Thanks for all your advice everyone!

PS: its nice to see imolas, nimmote, i have one too

MySTG3S4

I purchased a NEW rear caliper for $100 and my old one. If you dont want to deal with the rebuilding its an easy way.

jross13

Hello....

Same problem here and I found that I needed to completely remove the assembly in order the get any decent pressure on the piston to turn it and make it retract.

donromani

You guys need to go to autozone and get the loaner tool to compress the piston - it will make life much much easier. If that doesn't work then the piston is seized and you'll need to rebuild or replace the rear caliper.

bingS4

Yup, try to peel the boot back a little and see if there's some rust around the piston you can clean up. A local shop did this to my calipers when they were stuck solid and now they work perfectly.