I have a 2015 Silverado 2500 with 145K miles. The oter day the air conditioning belt started squealing and then burned/broke off. I was not using the air conditioner at the time. What do you think is the cause? Could it be just the clutch? Or has the compressor siezed?

 

Check to see if the pulley on the A/C clutch spins freely and is quiet. If it is ok then the problem is not there. How old is the belt and is it aligned with the pulleys?

 

Even if not using the a/c, remember it will run associated with defrost setting, so need to verify proper compresser operation as well. Spin all pulleys belt goes to verify smooth operation. If all are good, go back and look at a/c

 

The pulley does not spin freely but is locked up, however the clutch plate does spin freely. I suspect that the bearing in the pulley is seized. Does that make sense?