[steve-on-mark]

Well...since I do this for a living... a fixed caliper has pistons on both inboard and outboard sides so they don't have to slide and the pistons put equal amounts of pressure on the inner and outer pads. Floating calipers only have one piston on the inboard side... the " forks " on the outboard side apply force to the outer pads because the caliper is designed to slide on pins... the piston pushes in on the inner pads, while the forks push the outer pads as the caliper slides. I have seen these pins get very corroded and not allow the caliper to slide the way it was designed to which is why in this part of the world ( road salt ) servicing is recommended. I have also seen brake pads get rusted and seized in the brackets they ride in... there's nothing the pushes the pads away from the rotors when you let off the brake...they need to be able to slide freely. If the pads are seized, they stay in contact with the rotors, causing excessive heat build up leading to warpage. You should be able to remove brake pads by hand, but I've seen some that have to be hammered out of their brackets... that's why cleaning and lubricating is important as well. That is all...