You have a stuck piston. Take pads out and check the protective boots, One may be split and the piston is rusted, if so, new caliper time and brake hoses as well.

Then, you can check the parking brake shoes too.

__________________
Regards

Warren

Currently 1965 220Sb, 2002 FORD Crown Vic Police Interceptor

Had 1965 220SEb, 1967 230S, 280SE 4.5, 300SE (W126), 420SEL

ENTER > = (HP RPN)

Not part of the in-crowd since 1952.