how to stop a serpentine belt from screeching ?
Inspect belt and pulleys. If you are sure it's not a pulley going bad making the noise then I would just replace the belt.
make sure your tensioner is keeping it tight. You shouldn't be able to move it by hand. If you can without too much effort then there is your problem. If it is good then it is one of your pulleys or something is dragging and making the belt slip.
Search Chevrolet C/K 1500 Questions
Chevrolet C/K 1500 Experts