Ford Repair: brakes, caliper piston, ford explorer

Question
91 ford explorer, i am about to change my brake pads and possibly rotors.  i keep reading in haynes, and also in other places, about using a c clamp to compress the piston into the bore, is this necessary, and i am unclear on how to do this part, any details, or anything would be great, ii dont know if u have to do it to get the caliper off or back on or what, or once its off to get the actual pads out, please help, thanks, Sam

Answer
Sam:

The c-clamp is used to compress the piston back into the caliper.  As the brake pads wear the piston comes farther and farther out of the caliper to maintain pad contact with the rotors and thus needs to be pressed back in to provide clearance fot the new pads.  There are special tools available at parts/automotive stores that due the same operation but also protect the caliper/piston from damage.

Patrick