Make sure the calipers are free to slide in their mounts. Calipers are designed to be self-centering over the rotor, but sometimes rust will cause them to stick in place. I usually sand off any rust where the caliper contacts the rigid holder and put anti-seize on the surfaces that have to slide.

If the piston has to move out some extra distance to get the pad to contact the rotor, it's going to act just like you have air in the lines.

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'81 300CD - 180K, cannot be killed by any conventional means
'99 Ford Escort - good MPG