had a pig squeel when i 1st started on cool mornings and turned on the heater. once warmed up it was fine. tightened the belt and it's gone
note-when getting new serpentine belt, take the number off the old one-good chance you'll get the wrong one if you let them look it up. read it here alot and just happened to me. put the old one back on to take belt back and tightened the old one good-new one still in the package and squeel gone.