F150 A/c compressor
The answer is 'maybe'. Sounds like the pulley bearing is toast. When the a/c kicks in the magnetic clutch pulls the clutch plate onto the pulley hub (holds it in place taking load off the bearing). When the bearing goes completely, it'll throw the belt. Sometimes cheaper just to replace the 3-piece clutch than the whole compressor (I do that alot). If cost is a factor an AC bypass pulley is available. Take the compressor off and bolt the pulley in. There MUST be a pulley there for the belt to go around if it's a V8.