zeroptzero

the pads only go in one way so it is hard to mess that up. But you have to orient the slots in the caliper piston such that the nub on the inner pad slides through those slots as the caliper is lowered over the pads. If the slot of the piston isn't aligned with the nub on the pad then you get uneven pressure being applied to the inner pad. When you retract the piston into the caliper you need to make sure the slots of the piston point straight up and down in order to line up with the nub on the pad as it gets lowered onto the assembly. You purposely have to orient the piston as you turn it inwards, or you have to get lucky if you forget to make a point of doing it, otherwise there is a chance that it could be wrong.

xxmonsterx

anyone able to chime in on my issue for this? literally same deal but on the outside.
tore everything apart and everything is aligned perfect( tabs and piston + slider pins)
and my rotor seems to be true. i will post pics this afternoon.

SpitfireS

Stopping the rear caliper piston from turning (with that pin on the pad) is necessarry to keep the slack (caused by pad wear) out of the mechanically operated e-brake system.
That's why those grooves are in the rear piston in the first place.