Help diagnosing belt/pulley sound

[Natural_Nativ]

Help diagnosing belt/pulley sound (VIDEO)

My 4Runner started making a noise today either on the alternator belt or pulley itself. It has been squeaking loudly on start up for a while, but today the start up noise went away and now it sounds like a lower level squeak that is continuous and gets louder with higher rpms. I am currently trying to upload a video of the noise. The belts show no signs of wear or cracks and the print can still be easily read on them. What could be making this noise?

EDIT: Video makes it sound like it might not be coming from the belt/pulley, but I promise it is.
<embed width="440" height="420" type="application/x-shockwave-flash" src="http://v8.tinypic.com/player.swf?file=33myioj&s=8"><br><font size="1"><a href="http://tinypic.com/player.php?v=33myioj&s=8">Original Video</a> - More videos at <a href="http://tinypic.com">TinyPic</a></font>

 

[coltonbaxter31]

Have you got a new timing belt since you had the 4runner? If you havent i would get it checked or replaced. My 4runner started making weird noises like that and i thought it was just the pulley's so i ignored it for a while. Went away for the fall semester of college and around christmas it broke down on me. The timing belt and everything was destroyed and im lucky it didnt gum up my engine. It might be worth your time to get it looked at before you end up like i did lol

 

[Natural_Nativ]

Yes, timing belt and water pump were replaced less than 20K miles ago.

 

[s20004runner]

i didn't listen to the clip, but i changed the tensioner pulley for the ac compressor few days ago, which sits at the bottom of the engine.

I can't say it works every time, but my suggestion is run the engine for few mins and hold each belt w/ your bare hand. The hottest belt is the one making the noise cause of increase friction.

 

[Natural_Nativ]

i didn't listen to the clip, but i changed the tensioner pulley for the ac compressor few days ago, which sits at the bottom of the engine.

I can't say it works every time, but my suggestion is run the engine for few mins and hold each belt w/ your bare hand. The hottest belt is the one making the noise cause of increase friction.

I've confirmed that it is definitely my alternator belt.

 

[Natural_Nativ]

Bump
Does anyone have any suggestions on what it might be?

 

[mtnwkr]

Get a spray bottle of water and mist the suspected belt with the engine running. If the sound goes away it is either the belt or worn pulley. if not it is the pulley bearings.

 

[Natural_Nativ]

Get a spray bottle of water and mist the suspected belt with the engine running. If the sound goes away it is either the belt or worn pulley. if not it is the pulley bearings.

Thanks for the suggestion. I believe it is either the belt or pulley itself because I have tried this before and the sound will go away for a while. I was just concerned about the constant sound yesterday, but today after driving at interstate speeds for about 10 minutes the noise stopped. However, the squeaking is back at start up for a couple seconds.

Oh well, I guess I can deal with it for now until it warms up a bit.

 

[TheDurk]

So have you tightened the belt? I'm guessing it was installed new when the timing belt was done 20k miles ago and as it seated in and weather got cold it's starting to slip a little. New belts should always be readjusted after a few hundred miles but it doesn't happen in many cases.

Problem with waiting for warmer weather is your symptom may go away until next winter.