Purchased a 03 5.3 Tahoe last night. The drive home went smoothly but when we parked we noticed a sound that had not been present for numerous tests drives. I uploaded the video here https://www.youtube.com/watch?v=kB2P...ature=youtu.be. I know the video quality is poor I was more concerned with being able to convey the noise.

What could be causing this? fan Clutch , tension pulley ?

Thanks in advance