Squeaking/chriping sound on start

Hey guys,

I recently started hearing a very concerning loud chirping/squeaking sound on the underside of my 2013 Rock Warrior, it has 175k miles, and its been around 80-90 degrees outside for the past week. The chirping sound only lasts when the engine is cold, but goes away after a few minutes, it is noticeable after revving a little, no sound (normal v8 sound when going up the revs), and it squeals on the way down the revs. I have no clue what is causing the noise and its very concerning, as we know how reliable these trucks are. Just wanted to get some input and get some guidance.

 

Old belt?

Maybe your serpentine tensioner is getting a bit weak?

Mine does the same upon cold startup when humidity levels are high... and we've been getting a crap-ton of rain. I've not done anything to rectify the chirpy squeal, but assume it's either the belt or or one of the engine accessories needing attention.

 

Condensation trapped in the belt. Once the engine heats up, it usually evaporates any condensation left in the belt tracks.

 

So what should I do? So i narrowed it down to the left side (intake side) of the engine where the belt tensioner and vane pump are, sound like a pully problem, bc it still has sound when warm, which is new. So im thinking its the belt tensioner.

 

I think that's a solid plan.

Once mine starts doing it more regularly, or another symptom appears, I will probably start with a new belt and tensioner, and go from there.

If comfortable, remove the belt and start spinning all the pulleys by hand to see if one is noisy gravely or stiff. Just be sure to confirm the routing of the belt first. People get it wrong all the time and will make much worse sounds.

 

I second this. Just get the belt off and spin some things. You’ll find the issue soon enough. And if you don’t then come back here.

I had the same thing happen, first on cold start up, then eventually the chirp hung around the whole time the engine was on. I replaced the tensioner, idler, and belt at the same time and the chirp was gone.

 

Many moons ago when I was but a fit 200lb lad (Yeah, that's not a joke) I was advised that replacing those three at once was always the sensible option. Idlers and tensioners are usually cheap and if you've got to thrutch around replacing a belt in a tight spot you might as well skin your knuckles the once doing all the shitty little parts than run the risk of going through the whole palaver again before another belt is due.

 

There is a thread on here about how to diagnose and determine with part the noise is coming from. You tube video shows how to take a long screw driver and use a "funnel type item you make" to determine which part is making the noise. If I find the thread I will bump it up to the top of the page.
No telling what part it is. No sense buying parts you do not need guessing what is making the noise.

 

https://www.tundras.com/threads/how...-tensioner-idler-pulley-vs-water-pump.119592/

 

So just replaced the belt tensioner yesterday, it was the problem, i also needed a new belt as it was cracked under deeper inspection, I did a bunch: sway links, pads and rotors, and spark plugs. I also de-rusted the undercarriage and skid plate, and painted them, gotta take care of your prized possessions lol