I think mine are shot looking for a pair of stock ,rear, Brembo Sti brake calipers, in resonablely good shape.
There was a squeking noise during braking and driving so I had the rear pads replaced at Biker Boys shop. A week after there is a grinding noise I can hear when going 10-20( when the brakes ARE NOT ENGAGED). There is also very loud whirring noise at highway speeds that was not there before the pads were installed. Both sounds come from the rear of the car. This happened about a week after pads were installed. Car has 44,000 miles on it. The rotors need to be replaced soon, could the sound be from the rotors having wear on them and the pads still being squared off? Can calipers be rebuilt?
No, calipers can't be rebuilt at all! You should give those to me when you replace them so I can, uh, make them, er, into paperweights! Yeah, I collect Brembo, uh, junk merchandise! You won't have to worry about taking them to a scrap yard and pay to have them disposed, I'll get rid of them for you for free! (Note: I wanted to put the BS on a little thicker, but it was starting to stink.) Seriously, just rebuild them, you should be able to get a rebuild kit from Subaru if you really have to.
Did you have the rotors checked for warping? My rotors are warped terribly, and I have similar symptoms. Even down to the "I put in new pads and now it makes a whirring noise." Which is likely caused by the pads being thicker and lightly nicking the warped section of the rotor as it comes around. I would at the very least take your rear rotors into checker or autozone or wherever and have them turned.
I put in cheap pads until I can afford some better ones. They are the same brand as my fronts and they dont make any noise at all.
I guess I would have to hear the noise to know for sure, but if it's like all the other sti brake jobs I've done. I would guess the rotors have a slight ridge on the very outside of them, and it could be digging in to the pad. It could also be tire or wheel bearing noise, that you just started to notice. Just my two cents...