Metalic pads need a lot of heat (friction ) to work . without power assist theres no way to put enough pressure on them to work right . put a power booster on the truck or get the right pads. Not sure if you can get "organic" pads any more. Your pads are too hard.

71 challenger convertable, 64 sport fury 383 ci with factory air 99 sebring convertable 89 CTD pup