Brembo Caliper Rebuild Subaru STi:

5.) Remove the boot that is around the calipers piston. To do so you will see a small small hole between the boot and the caliper itself. I used a very small allen wrench, stick the wrench into the small hole and just pry out the boot it should just pop right out.

6.) After the boot is out and the piston is extended all that is left is to remove the piston. To do this you will need a screw driver and something soft like a towel. I wrapped the end of the screw driver in the towel and used the small lip on the piston to pry it out. Once the piston passes the seal on the inside of the piston hole it will pop and you can remove the piston by hand. WARNING: DO NOT SCRATCH/DAMAGE/CHIP THE SIDE WALL OF THE PISTON THIS WILL RESULT IN A BROKEN SEAL AND A USELESS PISTON.

Brembo Caliper: Inserting the pistons with new o-rings into the caliper.

7.) Install new dustboots on the pistons, these go on easily with hand. If they don’t you have the wrong size piston/seal and change the size. Do not try to force it on. Make sure the pistons and seals are wet with brake fluid for lubrication.

8.) Once u have it on, grab the piston and rotate the seal to ensure its on properly.

9.) Install piston seals. Remember there are two sizes install the proper ones to or you are going to have to do this all over!! Yes, they will fit in the wrong hole.

10.) Install the piston back into the caliper, gently place it in the bore and apply even pressure. Of it doesn’t go in with some pressure don’t try to force it, just try again and use some brake fluid on the caliper side as well to make life easier.