Hopefully the How-To that clicknext posted will help you out.
The "circle thing" is the piston in the brake caliper, thats what usually pushes your pads onto your rotor.
You have to remove the bolt on the back of a caliper and then use an Allen wrench to turn the piston back into its bore. Then when you put the caliper back on, you tighten the bolt down, then back it off slightly. (I checked by using my e-brake lever....)
Hey out of curiosity (because I might find myself changing the rear pads soon) is the part where you use an allen wrench to turn the piston back into its bore different from the front calipers? Because for the front calipers I remember retracting the piston using a C-clamp.
Do you need to re-tighten the allen key after you install everything? I have had some odd noise from the back since I did my break job and I thought (still think it might be) it was hucked up because I had to bore out the slide pin since it seized in there. If this needs to get re tightened though that might fix my problem with the noise.
Hey out of curiosity (because I might find myself changing the rear pads soon) is the part where you use an allen wrench to turn the piston back into its bore different from the front calipers? Because for the front calipers I remember retracting the piston using a C-clamp.
Yep, the back caliper is different from the front one because of the e-brake assembly in it.
C-clamp or pad spreader for the fronts, and the allen key for the back (and sometimes a spreader too if things are sorta gummed up there)
And el_Don is right, you have to re-tighten it. The shop manual that you can download from the link at the top of the P5 forum goes into how much, but I just tightened each side until my e-brake worked normally without being too tight.
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