Intermittent squeal - idler pulley?

[ElJayBird]

I’ve got a weird intermittent squeal coming from the motor. I got some video of it but by the time I got out and popped the hood it was gonna again. This was on Monday I think and it hasn’t come back since.

I went ahead and picked up a belt but not sure if this noise is the tensioner, idler pulley, just the belt, or...?

 

[TeCKis300]

My opinion is that generally, it's never just the belt. The belt squealing is a symptom of something else going on to have caused an issue with the belt/squealing.

How many miles and when does it occur? First thing in the morning when it's cold?

If the noise is consistent, listening for where it comes from, perhaps with a mechanics stethoscope (on Amazon <$10) is the easiest way to know where the problem area is.

As yours is not consistent, these may give you some clue
1) With engine on - look at each pulley and idler to see whether they spin true
2) With engine off - feel for play on each pulley and idler
3) Spray water on the ribbed side of the belt - if it squeals louder, the tensioner is failing and not putting enough tension on the belt

 

[ElJayBird]

It’s got about 92k on it - I’ll grab a scope from
Amazon and wait for it to come back. It’s extremely intermittent and I’ve had it happen on cold start and after driving for a while.

 

[04UZJ100]

Same thing here. Extremely intermittent - typically on damp cold mornings. I am going to replace the serpentine belt when I have time in the next month.

If it’s anything like the 5.7L Tundra - it looks easy.....

 

[OregonLC]

If it's squealing when it's cold it's probably not the idler but drag from the PS pulley. Takes a while for the fluid to warm up and flow.

 

[DecreedIt]

Got the same thing, started a couple days ago, was intermittent, now 'always'. 176k - belt and Water Pump done at 146k - never any pulleys or tensioners.

Was slight at idle when cold, quiet at idle when warm but tracks RPMs for sure. What's the most likely culprit? Gotta knock this out quick, 5000+ mi round trip NC to CO coming up in less than a month.

 

[DecreedIt]

Ah, found this, I'm guessing this is in my near future: Belt, Pump, Tensioner & Pulley - The $400 chirp - https://forum.ih8mud.com/threads/belt-pump-tensioner-pulley-the-400-chirp.1180285/

Waterpump, belt only have ~ 30k miles . . . neither seems necessary. Belt looks great, no cracks or shiny. Unless of course the @#$% pulley fails or is binding between now and when I get to it.

 

[TXMeatball]

Don't think these like aftermarket belts very much. Had a squeal that'd come and go which gradually became more common after running a bit. Took out some aftermarket one PO put in and replaced it with a bando 8PK2410. Played with tensioners/pulleys while belt was off, they seemed fine. Haven't had squeal since.

 

[04UZJ100]

Never put anything other than OEM on your truck except for suspensions components. There is no comparison in quality OR compatibility.

 

[Cruisin911]

Had the same chirp on my tundra. Change the tensioner and idler while you're in there with an OEM belt. That'll fix it.

 

[NDizzle]

I had to replace my fan clutch at about 150k miles. Talk about a nasty squeal when that thing starts binding up. I don't think that is your issue, but it's definitely something that can (will?) happen eventually.

 

[ElJayBird]

Mine was the tensioner pulley. Replaced that and the belt.