Hello I have a 1996 F 350 Power stroke 7.3 XLT centurion 2 wheel drive crew cab dually with cruise control. When I got the truck it had a very soft brake pedal that would almost bottom out even after pumping a few times. I have since replaced calipers, pads, wheel cylinders, shoes, left rear emergency cable, booster & master cylinder. After bleeding the old fashioned way with two people throughly the pedal still acts the same even though I can hear and feel the calipers and rear brakes grabbing.Is it possible the ABS cylinder could be bad as well and or does the bakes have to be bled while attached to a scanner to make them function properly? Or is it possibly a simple vaccum problem? Even though all seems ok with the vaccum lines.