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[Snigalfriz]

Gents,

I was replacing my rear brake pads, and I cannot get the piston to push in far enough to fit around the new pads.  I regular change the pads on my other car.  I have a tool to push the piston in, but I still cannot make enough room.

The parking brake isn't engaged.

Am I missing something?

[Rocketman]

I'm sure you know, the piston has to rotate in order to retract.

It will retract just about flush with the caliper

[Snigalfriz]

Thanks, I was not aware of that, my other vehicles that wasn't the case.  Which direction does it turn?

[rcdraco]

I believe it should turn clockwise.  Doesn't clarify in the manual, but that's the standard direction.  

You need to apply pressure WHILE turning it in though to get it to turn in.  The reason that this differs from the brakes you've dealt with is that rear brakes need to do the job of both parking brake, and regular brakes.  This can be accomplished by either parking brake shoes inside the rotor, or by rotating the piston outward to apply pressure onto the pads.  The former is more common on large vehicles, with the latter being more common on small diameter rotors/small vehicles.

[Snigalfriz]

Thanks

[Snigalfriz]

Replaced pads all the way around. Very grippy now.

[JoeinJersey]

What do you use to turn and push the piston in at the same time? (On other cars I just used a c-clamp to push in the piston)

[rcdraco]

It's a specialized tool, 6 sides, 5 tools for different calipers to allow you to rotate it while compressing it via a 3/8" drive.  Any parts store should have like 5 of them.  Normally run about $15.  Some cheaper people have used needle nose pliers, I wouldn't recommend doing anything that stupid right next to piston boots which can be 10 or more years old.

C-Clamps can be used on front brakes, and on specific rear brakes.  On integral parking brake systems you will need to rotate while compressing the piston otherwise you will damage it.  Which is what Capri's use.