Loud screeching noise

[BBQ BOY]

Is coming from under the hood. It only happens at higher RPMs in every gear. Sounds like it's coming from the belts area. So is it a pulley, and if so, what do I need to do about it?
This is the first it's happened and only after driving 5 hours at 60mph

 

[Vernon]

Is coming from under the hood. It only happens at higher RPMs in every gear. Sounds like it's coming from the belts area. So is it a pulley, and if so, what do I need to do about it?
This is the first it's happened and only after driving 5 hours at 60mph

Smog pump going out? If you have one.....

 

[BBQ BOY]

I de-smogged the Pig several months ago. It was making a lot of noise as well, but not this kind of noise.

 

[LAMBCRUSHER]

you could pull your belt and turn your pulleys to check for bad bearings/noise. you might just have a loose belt. the alt and water pump could both be culprits, also, check you isle vacuum...you could have developed an intake leak that might be whistling