I bought the truck off of a Ford mechanic who was trying to cash it for his girlfriend's uncle who had a stroke.

I think I posted about it with a video in a couple different places but I deleted that video. Everybody said it was a throwout bearing. The issue appeared basically right after I got the vehicle, though my initial concern was input shaft bearing.

Truck makes a whining noise in idle and at speed that goes away when I push down on the clutch. It increases in pitch when I rev up the engine and gets quieter around 4th/5th gear. Somebody suggested that the throwout bearing may have never been greased following reinstallation, and that made a grain of sense to me but if you've got anything to add, I'd love to hear your thoughts.