Squealing chevy tahoe belt

I got a great deal on an 01 Tahoe in which the belt squealed. Figuring it was either the actual belt or the Idler pulley, I thought it’d be an easy fix. Well, I’ve since changed everything the belt rides on (both belts (twice), pulleys/tensioners, the alternator, water pump, clutch fan, etc.) and the squeal is still there! I have a feeling that something one of these parts connects to is either cracked or bent causing the belt to ride just a little off & still squeal. Can anyone offer any other suggestions? I’ve heard of a couple other Tahoe owners having the squeal & just accepting it as characteristic - NOT acceptable to me. PLEASE help!!!

No, it is not acceptable. That remark sounds as though it came from a service writer.

I have a 2002 Tahoe with 126k miles and never had a squeal from anything. (Perhaps just lucky)

Perhaps the A/C is squealing. You can eliminate this possibility by turning the defroster on high or turn on the A/C itself on high. If the pitch in sound changes or goes away, you MAY have found the culprit.

I emphasize the word ‘may’ as the engine takes more of a load while the A/C is working and may detract from another source.

To check for pulley alignment, use any straight edge (ruler or yard stick, etc) place against the face of two pulleys at a time.

Try this: take a water spray bottle (the type with a trigger) and while the squealing noise is present, squirt a LITTLE quick stream at the point where the pulley shaft enters the suspected unit. Do NOT saturate it.

If the squealing stops, that MAY be an indicator of a bad bearing.

FWIW, that is a very expensive method of tracking down the source of a squeal.

THANK YOU for your thoughts. I forgot to mention the A/C thing we’ve ruled out (no difference on or off). The MOST dramatic difference was when we lubricated the clutch fan (before replacing it), but since replacing it - still squealing. The squeal has gotten worse as we’ve replaced parts (I believe now with all the new parts whatever is still wrong, is only being pulled harder/tighter on).
I will try the water thing. Have you any suspicion where this bad bearing may be? The squeal seems to be coming from the very middle near the front.
Yes, this has been an expensive, but more so time consuming ordeal only to still have a Tahoe that’s beautiful, but is embarrassingly loud.
Again, thank you for your input!!!

Have you tried running the rig for a few seconds with no belts installed, just to make sure that it’s actually related to them?

Yup!! Afraid so. Definitely something to do with the belt (P.O.S)

My 2000 Blazer is fussy about serpentine belts. I installed a new Dayco Poly-V and it was noisier than the 3 year old belt it replaced (no squealing though). I replaced it with a Goodyear Poly-V and it was much quieter. I’ve had good luck with Gates and Goodyear belts, but prefer Goodyear.

Ed B.

Which bearing? Good question for which I have no positive answer.

You claim to have replaced practically everything that moves, so maybe you can tell me if anything is left?

Haven’t messed with the drive train. That’s about all that’s not been replaced.