I bought front and rear oem pads because my current set need replacement. The front pads came with 2 different colored greases, a brownish grease and a black grease. Im guessing the black is the one that goes on the back of the pads & inner & outer shims, but Im trying to figure out where exactly the brown one is applied. Is it for the pad retainers? Also can either one of these be used to grease the sliding pins. Anyone?