There was at first, but I changed the bearing in the AC pulley, now there’s no difference with it on or off.

 

You're saying that you solved the problem? It was the AC pulley bearing causing the noise? No difference good or no difference still bad.

 

That noise from the video sounds like bad bearings .

 

I'd do as suggested, pull the belt and spin all of the accessories by hand. I've had brand new pulleys that made noise out of the box.

 

Did you inspect the tensioner as suggested earlier ?

If those get loose they'll begin grinding the pulley against the front cover.

 

I've had perfectly good bearings that were low on grease... Dried out and hardened.. make a lot of noise. Instead of shelling out the money for a new bearing I just removed the side shield, greased them snapped the side shield back in and was good to go quiet....

Sometimes when you compare free to $50 you choose free