Squeaking/chirping in belt drive area - 5.7 Hemi

I can't isolate this squeaking/chirping, bird-like noise at idle on an '08 Aspen, 5.7L. Only hear it after it warms up and it gets worse with some load (a/c on or sawing the wheel back and forth). It goes away at anything above idle.
I thought I had it isolated to the tensioner pulley. Changed it; didn't help. Have since changed both idler pulleys and the belt; no change. Everything felt smooth, 'normal' with the belt off.
I can't seem to isolate it with a stethoscope. Any ideas on which bearing/accessory would be most likely?
Thanks!

If the belt is good then I would question the tensioner. When they get weak the belt can squeak.

I had a 1978 360 do that. It turned out to be something failed internally on the fan clutch. Replaced the clutch and
problem stopped. I'd previously replaced the belt and couldn't "feel" anything wrong with the fan clutch working it by hand,
but replacing it stopped the noise.

I'd feel the pulley on your water pump too and see if there's even a slight wobble. It may not be leaking yet but be getting weak.

Electric fans

Most likely this guy is the winner. I wish I had the patience to post a video, I took one after the pump started to let go on a 5.7 in a grand cherokee. No difference in operating temps, just an occasional squeel or chirp. Very embarrassing when picking the kids up from school


Also, take the belt off and run it for a few seconds...

The belt tensioner was causing intermittent squealing on my son's 5.7. It wasn't always keeping the belt tight. I've seen this on 3 other various year and drive train Mopars recently. Defective belt tensioners.

He said he replaced both.

Get a mechanic's stethoscope and start listening to various thing. No sense spending money you do not need to.

From orig. post: I can't seem to isolate it with a stethoscope.

Or a pry bar or long screwdriver that has metal to the top of the handle.

Said he replaced the tensioner pulley and the idler pulley, nothing about the tensioner itself. They sell a kit that has both pulleys with the bearings, but does not replace the tensioner spring assembly itself.

Hey guys,
Thanks for all the responses.
I did replace the tensioner pulley but not the whole tensioner assembly. May have been a mistake there. I pushed down on it slightly with a stick of wood (while running) to simulate a tighter spring and don't think it improved it. I'll look at it again.
Not sure running it without the belt would tell me anything. None of the possible offenders would be turning
I'll recheck the water pump for any slop. Did this earlier and didn't notice anything amiss, but I'll make sure there's ZERO play.
Any other ideas or experiences are appreciated.

Oh. The fan clutch reply is interesting too. It does have a mechanical fan.
Has anyone had noise from their fan clutch on a Gen 3 Hemi?

My truck is an '01 Ram with a 5.2. In my experience, belts are horrible these days.
About a decade ago I had a squeal that I would have bet money was coming from my A/C pump. Took my truck to a local guy that I trusted, opened the hood and he said "that's your belt." NO WAY...it's less than a year old! He put some soap on it to prove it to me...
I think Sniper has the right answer. IF it's something other than the belt, a stethoscope might save you some money...

EDIT: BTW, I now use "lifetime" AC Delco belts (from Rock Auto) that last about 3 years, and I'm OK with that.

Yes..a general rule of thumb the trucks usually have a belt driven fan, the cars have electric.

Not sure, usually it's a tensioner or similar on a serpentine, but just throwing the idea out there since it's a possibility.

good luck

Still say it is the tensioner. I had one drive me crazy until I replaced it.

So, have you replaced the entire belt tensioner, or do you still think the original tensioner is OK and all those belts were the problem? I have serpentine belts that are over 6 years old that do not squeal. I have replaced a few belt tensioners though. After 5 or 6 years, the coil spring and the free movement in the tensioners don't function like they were designed to work, especially in the limited movement area they usually operate in.

Get a Good Year Gatorback belt. It stopped my squealing belt problem.

Yes. Well...remembering back (and knowing me) I'm certain I went through all that before I searched for outside help. It's possible that I missed something, but there ain't much to miss. When (not if) the chirp re-appears I'll address it without assumptions. Thanks...I needed that nudge.

Do you have a specific brand of tensioner that you run?

I bought mine from the dealer.

i had a belt squeal on my caravan that drove me nutz,,,,,,,,,,
replaced all the pulleys and the tensioner. also used the gates belt.
checked pulley alignment, bearings in the water pump, alternator, and power steering pump. all were good.
as a last resort, i spritzed the belt while running with one of those belt quiet sprays, and to my amazement, it has been quiet for over a year and a half.
i have no clue why those spritzes worked, as the belt was not glazed, nor were any of the pulleys. so who knows ?

Put some comet kitchen cleaner dust on the belt. If the noise is gone its the belt.

Thanks for all of the replies. Wanted to close this out. Dug back into it and found some play in the water pump bearing. Replaced pump and all is well. Never would have guessed it from the sound. Live and learn. Thanks again to all.

glad to hear it was a relatively simple fix.

Good to know. Thanks for getting back to us on it.