The piston in the caliper might be sticking cause the caliper is dirty. Before pushing pistons inn go to auto parts store and buy some break cleaner. Spray them down good. Now set old pads in place and with a flat screw driver put between old pads and twist side ways to force pistons in.
Do not push on pedal till new pads are in place mounted on rotor.
Go to Dennis Kirk and order some EBC pads they stop 80% better then stock. You'll have to search first for p/n
Once new pads are in place listen for dragging or if you can get back wheel off ground spin wheel and listen for dragging.
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