I'm trying to install new Rotora drilled/slotted rotors and Project Mu NS brake pads. I've had no problems installing the rear driver's side combination, but I'm currently not able to install new pads on the front driver's side because the 2 caliper pistons on the left are stuck.

Initially, the 2 bottom pistons were stuck, but I was able to free the bottom right piston and fit in a new brakepad on the right. However, now both pistons on the left side are stuck out and there's no way I can install the other pad.

I've searched for answers on this forum and on Google, and I've tried everything I could find to no avail. I used a flathead screwdriver and wedged it between the piston and rotor, a C-clamp with a towel protecting the caliper, I've removed the brake reservoir cap, opened both bleeder valves, stepped on the brakes to see if the stuck pistons would move at all, and at one point I even squirted some WD-40, but they refuse to budge!

Do I need to take the caliper apart? Is this a pressure issue?

At this point my car is out of commission because I can't even put the old pads back on. Any help at all would be greatly appreciated!

 

i beleive you need to rotate them back, you might need a specialty tool to do so or be creative...

 

Front or Rear Caliper? Anyway do yourself a favor and make sure the brake line isn't kinked. If it is then there's no way of the pressure pushing the piston back in. If all else fails, I'd say your caliper is seized. You can rebuild it, but that's if you have the experience in that. I use a brake spreader this one. You put the pads back in and put this in the middle and spread 'em. Wonderful tool, I bought specifically for quad pistons.

 

What did you use to seperate the pistons, (they all have to go in at once) also try emeroy cloth to clean up the piston that may help.

 

The pistons dont spin in....you have a pressure issue. if you cant get them to move--take your brake line loose--that should take care of the problem--pistons will press in.

 

please pm me where u can get this tool. thanks..

 

When you put the car in neutral does it feel like it wants to stop it's self?

 

Take the caliper off, grab a couple of wooden blocks and compressed air and carefully pop the pistons out and buy a rebuild kit from Girodisc.


Might as well do both fronts.

 

That tool works good if you have a two piston caliper. For the front you will need 2 of them because as you push one in the other will come out.

We have a tool similar that works great on EVOs and all the way up to 8 piston calipers.

 

I had this problem one day when I melted my pads on the track, the piston just came out too far. Rotate the piston back and forth, it will go back in.

 

Thank you to everyone for all the advice! I really appreciate the help.

I actually ended up using both a C-clamp and a Kant Twist. After a bit of playing around and pumping the brakes a little now and then, I was able to compress all pistons simultaneously. New rotors and pads are now in place!

Happy Holidays!

 

I disagree I've used the tool on numerous quad piston applications, i.e. Lexus', TL Brembos, G35 Brembos, etc... It's only $26 too.