The video is helpful. I certainly hear it. If you have a line on the belt indicating wear, are you certain the belt pullies are aligned, and the belt is riding flat on all pullies?
Open the hood and locate the wear mark and then by eye, follow the belt around to see if it is not aligned on one of the pullies. Also, if you could upload a pic of the belt wear mark, it may help me.
As far as the fan noise, I'm not sure where you are located, but if it is warm, the fan clutch will fully engage when the under-hood temp reaches a predetermined temperature. At that point, it is very noticeable. When you leave off the gas, it will slow and not be as noticeable.
Now, since the noise seems to happen when you let off the throttle, check at the water pump pulley to see if there is play in the pump bearing itself. Additionally, confirm there is no contamination on the belt from coolant or other fluid.
Here is a link that explains what to look for when you have a screeching sound from a belt, but I feel you already have taken care of what is mentioned:
Let me know what you find.
Friday, January 7th, 2022 AT 6:59 PM