Rear brake caliper with integrated parking brake

[Burt Shaver]

Merry Christmas everyone, first off wanted to thank everyone for all the advice here, posted a few threads and have received lots of great advice from those who have the experience.
So I changed the rear brakes on my 2012 Mazda 3 and all went well but I noticed one of the dust seals for the piston was cracked and I want to replace the boot. I have a full caliper rebuild kit as I needed the dust covers for the slider pins as they were missing and the one caliper was sticking slightly but it seems to have improved now. Anyways, for a regular caliper piston I think I fully understand how to remove it by simply taking the caliper off and gently pressing the brake pedal till the piston is almost fully extended but this rear brake has the integrated parking brake which needs to be turned clockwise while applying pressure to retract it. My question is how do I go about extending the piston out of its bore so I can change this dust boot? After removing the caliper do I simply press the brake pedal so the fluid will push it out? Or do I cycle the parking brake to push it out? Which I’ve seen done on a couple of video’s with the caliper completely removed from the car. I however don’t want to completely remove the caliper. Or so I have to remove the hand brake cable from the lever on the caliper and then cycle the hand brake lever manually right at the caliper, this way makes sense to me, but I’m not sure at all since I’ve never done it. Thanks for any replies

 

[Wrench97]

Remove the nut on the back and pull the shaft out with the piston, there is a o ring for the shaft that should also be changed.
It's been awhile since I've done one since it's cheaper to buy them rebuilt then buy the kits and pay the labor rates to do it.

 

[Burt Shaver]

Remove the nut on the back and pull the shaft out with the piston, there is a o ring for the shaft that should also be changed.
It's been awhile since I've done one since it's cheaper to buy them rebuilt then buy the kits and pay the labor rates to do it.

Even though I bought the full rebuild kit with new piston I really only need to replace the dust cover now that it seems to have un stuck itself, it wasn’t fully seized, it was just hard to push back. I was hoping to push the piston out enough to change this dust seal without removing the brake line but I’m not sure how to push it out, is it by pushing the brake pedal and using the hydraulic fluid to push it out some or should I be cycling the parking brake lever? I may do a full rebuild on the caliper at a later time or if I find that it’s still sticking a bit.

 

[Wrench97]

If you are just changing the boot there should be no need to push the piston out, just pry the boot out and use a large socket or pipe to knock the new one in.
It may have been sticking at the the end of the bore from pitting or the end of the ratcheting mechanism.

 

[Burt Shaver]

If you are just changing the boot there should be no need to push the piston out, just pry the boot out and use a large socket or pipe to knock the new one in.
It may have been sticking at the the end of the bore from pitting or the end of the ratcheting mechanism.

Ok, I will give it a try. I had just put new pads and rotors on so the piston is set back in the bore pretty far now because of the new pads. I thought it might be a little easier to install the boot with the piston out a little bit. Also thought I might have seen that you can use the caliper tool and twist the piston to the left to bring it out a bit? I would think just pressing on the brake would push it out same as with a caliper without the parking brake. Anyways I’m sure I’m making a way bigger deal than it needs to be, I’m sure once I get at it, it will be easy peasy. Thank you for the replies

 

[Wrench97]

You can put a little pressure on the brake pedal to push it out just don't push it all the way out

 

[Burt Shaver]

You can put a little pressure on the brake pedal to push it out just don't push it all the way out

I’ve known that this can be done with a caliper without the parking brake but was r sure about this one with it, I’ve probably spent upwards of 4 or 5 hours combing through you tube video’s to find out how to push these ones out and just while speaking with you I realized they can be pushed out the same way. Tell me if I’m wrong but I couldn’t see a problem even if it did come all the way out, That’s what would need to be done if I wanted to clean up the piston on a brass wheel anyways, then just remove the square oring in the bore, clean up where that Oring sits, clean it all out, lube the oring and push/twist the piston back in. I think anyways.

 

[Wrench97]

It should not come off the shaft of the p/brake ratchet, that's why you have to remove the nut and push the shaft and piston out but it can come out far enough to leak all the fluid out and you'll have a heck of a time trying to get it all back together into the bore and treaded down the shaft.

 

[Burt Shaver]

It should not come off the shaft of the p/brake ratchet, that's why you have to remove the nut and push the shaft and piston out but it can come out far enough to leak all the fluid out and you'll have a heck of a time trying to get it all back together into the bore and treaded down the shaft.

Thanks very much for the warning, I will try and gently push it out only an inch or so. If I decide to rebuild it I will take the caliper right off and do it right, well at least try to do it right. Thanks again, Merry Christmas

 

[yellowbox]

It ain't leaking, leave it alone......just saying

 

[Burt Shaver]

It ain't leaking, leave it alone......just saying

Probably should replace the torn dust cover though? Thinking it will seize up pretty quickly here in the salt and slush

 

[yellowbox]

Probably should replace the torn dust cover though? Thinking it will seize up pretty quickly here in the salt and slush

Didn't you say it was already sticking?
If it makes you feel better replace the whole caliper, this would then eliminate both issues

 

[Burt Shaver]

Didn't you say it was already sticking?
If it makes you feel better replace the whole caliper, this would then eliminate both issues

It was sticking a little bit right after I put the new pads and rotors on but seems to have freed up after a few drives. Yeah, it would be easy to just spend the 150.00 and put a new caliper on, I enjoy working on things lately and learning. From what I see a lot of times, the caliper can be dissembled, piston cleaned on a brass wheel, new rubber kit is about 5.00. And put back together good as new.