My tensioner pulley squealed really bad after spilling coolant on it. I think some got into the bearing. It took several weeks but it went away on it's own. Have you tried belt dressing? It may be an issue with the AC clutch.

 

At least yours will stay on! lol I keep spiting them off. Does any one know if you can use a belt for like a 2010+ Camaro that doesn't use a tensioner??? Just stretches on??

 

I had a similar problem with mine and it drove me nuts, everyone stared as you drove by..talk about being at the center of attention. Anyways, it was the tensioner. Easy way to find out is take it off and spin it, if it has ANY vibrations or sounds coming from it then I would say its junk. It should be smooth and stop shortly after you spin it. I replaced mine with the OEM stuff so I can't comment on the cheaper ones. Have fun dealing with it, I know I did!

 

I've seen the cheapo tensioner bearings fail, not on the pulley itself but in the tensioner pivot. If the tensioner has any stiff spots it will definitely cause a squeak. Also, I don't particularly like the Gates belts. They're good and all, but most of the ones I've used developed a squeak. I like to use either Dayco or Gatorback belts.

I think the Gatorback belt for the A/C is #4040377

 

Here is what I suggest based on my experience with this issue:

1. Discard both engine belts.
2. Spray all pulleys with brake cleaner. let dry.
3. Spray all pulleys with brake cleaner again. let dry.
4. Put on new belts.

 

Get you a wire brush with the engine running... (Carefully ) let it ride on both sides of the belt for a few seconds, spray the belt with brake clean, and wire brush one more time. This worked for me. Sounds crazy and you could lose apendages but it worked

 

Well if he has his appendage hanging out over the drive belt and it gets lobbed off its his own fault . Lol

 

**** i would shove a wire brush up a donkeys *** and twist it if it would stop the squeal.

On a side note i ordered new gatorback belts and an OEM tensiorer.

 

Mine only chirps with the AC and more than part throttle driving. After a WOT pull, it will let out a loud chirp. After reading this stuff, I am worried its the clutch on the compressor..

My parents have an 02 5.3 Yukon and theirs makes a chattering, or grinding noise with the AC on. It makes the noise right as the transmission shifts. They were quoted it needing all kinds of parts to fix this. That true?

 

Well new gatorback belts installed and new OEM ac tensioner. So far no noise.