2007 Toyota Tundra 4WD Truck - Squeals

My tundra idles quietly starts to squeal when I increase rpms. Is this a tightening issue or tensioner issue. The belt was replaced 3 years ago. Thank you Doug

Yes, or you have anything driven by the belt dragging.

The “anything dragging” could be the power steering pump. Check the fluid level if you haven’t recently.

I’d take off the belt and check everything that turns.