The ac compressor on my 2000 Blazer with 149,000 miles is making a whining noise but not all the time. When it kicks on the noise stops but when it goes off the noise starts. This is the second compressor...the original one definitely bit the dust and I replaced it. Since the air was not as cold as it was I added a can of freon 134A. The air is now colder but the noise is still there when the compressor cycles off. Has anyone here had a similar issue and what was the fix.

 

sounds like the bearing in the compressor

do a search im sure something will come up

 

Actually in the clutch:
See here:
https://blazerforum.com/forum/2nd-ge...-needed-67518/

If you do your own wrenching, you have a great adventure a coming. Everything in that thread applies to you. You dont have to remove the compressor.
I strongly suggest from my experience you replace the clutch pulley assy. You have time to order it and the tool if you dont screw around.