Not Enough Clearance for Rear Brake Pad
 

Hey guys,
I've been trying to install some Hawk HPS brake pads. Front went quick, but the rear has been a huge bitch. I've managed to spin the rear pistons to kingdom come, and still there isn't enough clearance for the pads to fit between the caliper and the piston.

Here is the extent that I've retracted the piston: http://db.tt/yE9LtwoI

Should it be able to go further? I have the problem on both rears.

Please help ASAP!
Thanks,
John

Push HARD on the piston while you turn it clockwise...it should fully retract

Install new pads .... :)

I don't know what the deal is with that, but I just dealt with that in a week-long saga of pain. I've never come across ANY rear brake job like it. Ended up pulling some that were thinner from another set, and ... flop. Hope it works out forya...

Your just doing it wrong.

M A Z D A

^

DISC PAD (REAR) REPLACEMENT

disagree. the calipers/procedure is not different from any other typical japanese car, but it is an extremely, extremely tight fit on this vehicle for whatever reason.

had to take off the aluminum shields my pads came with.

You can disagree all you want, I have done it many, many times without issue.

Align the markers and you'll have zero problems. QFT.

ohhhhhhh.... those secret notches that only exist on RX-8 calipers? :rolleyes:

Managed to do it after about 3 hours of pushing and spinning. That was the most painful job I've ever done on my car.

I also lost a good amount of brake fluid, so I got to do a bleeding today! What joy these past hours have been...

For future people facing this, the piston WILL go far enough. If you're using pliers like I had to, focus more on pushing in as you turn. Turning with little push will not get you anywhere.

Cheers

Unfortunately yeah... using something like pliers rather than a caliper tool is going to make it harder than it should be too.

All that trouble for a $9 tool ;)

There are proper tools for everything :)

they exist on our Mazda 5 too:)

Congrats, You just figured out something that everyone who has changed pads on a similar style caliper, or everyone who had read a DIY or manual already knows. :ylsuper:

One of my first, and now proudest, purchases, Dan... Expo1 stepped me thru it, complete with links to harbor freight, back when I was a newbie.

Try pulling the piston all the way out and inspect the housing (or whatever you call it). Mine developed a groove which the back side of the piston would sit in and not retract any further. If i lubed it up real good i could get the piston back in no problem but the whole process was a pain in the ass.

If your pads are in fact too thick you can get them milled down. I'm not sure if any ole machine shop would be able to do it but i had to have a race shop mill down a set of Colbalt 20mm pads to 16mm so they would fit. I wouldn't normally do this but i was in a pinch. 16mm pads were made to order but i didn't have the time for them to make them and ship them.

Yeah... probably the only time I've ever done anything like this. I'm sure all fits well if you use "Mazda" parts... I didn't... won't lose sleep over it...

piler ... that explains it all ...

they designed and sell something called "caliper" tools ... it existed for a reason ... yeah ... for like 10 bux ... you didn't use proper tools ... and bitch ...

https://www.rx8club.com/attachment.p...1&d=1346533274

IIRC, you can drop a deposit down at Advance or AutoZone and rent the tool for free(you get your money back if you don't break the tool). That could save you some trouble.

As others have said, make sure the notch is lined up on the back/top of the piston as well. It won't fit into place if not.

You can get your money back even if it breaks, or at least that is what they told me at autozone when I rented a serpentine belt tool.

I just did my brakes tonight. Havent finished and im gonna wait until tomorrow. Last time i took my brakes apart (just to paint the caliper amongst other things) i only had to slightly turn that piston and channel locks did just fine. This time however... i used the channel locks and managed to get it almost all the way down...but i feel it still may be too tight with the new pads.

Im going tomorrow with my sisters car to get this SST.

BTW, maybe im not the only one...but anyone ever have a problem with the rubber boot on that piston? Seems like when i turn it, it doesnt recess properly (or whatever) and it is wound up. This may be preventing me from getting the piston all the way in.


Aside from all this...the fronts went smoothly except for one of the pins in the passenger caliper being frozen and rusted in (fixed with some liquid wrench, a hammer, vice, and serious leverage).

anyone try un-adjusting the parking brake? If you take up extra slack by adjusting it then replace the pads you're not going to be able to compress it all the way..