Squeaking belts/tensioner??

[Chris97K1500]

My Brother in laws '02 Tahoe has a pretty bad squeaking sound coming from the engine bay area, constantly, at idle and while driving. At first I thought it was just a loose belt or something that would be fixed with STP Belt Spray. The squeak went away at idle after putting the belt spray on them (probably just for a few days), but it's still there when you rev the engine to about 2K rpm's. It doesn't get louder as you get faster, just a constant high pitch squeal. At this point I'm thinking a bearing is going out. Any ideas? They are still under warranty, so they are going to take it in, but I would like to be able to give them a possible diagnosis, just so the dealer can't tell them just anything. Thanks, Chris

[gutlessTahoe]

might be the Serpentine belt since it went out on mine when I first bought my Tahoe.

[02 Silverado Z71]

Using ANY kind of belt dressing on serpentine belts is a NO-NO! Don't do this. Just makes a mess out of everything. I have seen some of this crap stuck on belts and pulleys - what a mess. I have also seen vehicles TOWED IN because they threw the belt off after sparing this crap on the belt!

Most likely have a noisy belt. Look very closely in-between the ribs on the belt. If you see ANY signs of metal showing in-between the ribs, this condition will cause a squeak.

Don't worry too much, you are still within factory warranty.