How do you retract the brake cylinder on the rear brakes for new pads on a 2004 Mercury Monterey?

The rear disc brake piston needs to turn as it is retracted / compressed into the caliper.

Go to the parts store and tell them you need the brake cylinder retraction tool. Cost about 10 bucks and works for a variety of cars/vans.

It is a square with a couple of different teeth on each face, to align with the notches in the face of the brake piston.

Should work with a 3/8 drive ratchet. Clockwise facing the cylinder to retract. Have fun!