Brakes were replaced on a 1997 ford explorer xlt all they do is squeak now they have been looked at twice by the person who put them in and another mechanic they cant find anything wrong whats wrong?

Needs Hi-temp brake pad grease on the back side of the pads. This should fix the problem if rotors are new or have been turned as well as new brake pads. Brakes squeak from a variety of causes. Is it a front or rear squeak? You may need to have the rotors turned or replaced if no one is able to turn them.