Thanks gm trucker.
The AC compressor is not on the serpentine belt but is on a secondary V belt coming off the crank and serves only the AC compressor. I believe that belt is most likely factory original.

Are you saying I can lube the clutch? I have never dealt with an AC problem like this before but I thought the clutch would have to be dry, won't lube make it slip more?? Sorry, kind of a noobie question I suppose!

Thanks in advance.

 

I agree with changing the belt first since it is inexpensive. But while you have it off, try turning theA/C wheel by hand to check the bearings, and any inappropiate wobble in the A/C wheel. Also check any wheel that this belt goes to. If all is OK, replace the belt. If still no better, then start looking at the A/C clutch. Make sure the noise is coming from the clutches before you do all that work though. Let us know what you find, as it may help others. And f we can help further, just ask.

 

Thanks for all of the help and suggestions all of you made, you truly saved me time and money!
Today I picked up a new A/C Compressor belt, not the long serpentine belt but the small belt that drives only the AC Compressor, and when I was removing the tensioner to install the new belt, I guess I accidently stumbled across the problem!
As I turned the tensioner with a ratchet in the clockwise direction to releive tension on the belt, the tensioner stayed "stuck" in that position, so I removed it and replaced the belt and upon further inspection the tensioner appears to be shot, internals are most likely corroded to the point that the tensioner cannot travel and maintain the appropriate tension.
So...quick trip back to the parts store for a new tensioner ($40) brought it home, stuck it on and works like a charm!! No more screeching!!
Thanks for all the help everyone!
MY truck has 140K on it, I replaced the main serpentine belt and tensioner at around 95K and now this today.

 

Glad we could help you out. And that is was an easy and fairly cheap fix. Nice job to the rest of you as well.

Hey we finally got one right and actually did help someone! Ha!

 

Glad to be of service