Wa-oh-wa-oh sound on start up (VIDEO)

cant tell where its coming from. Not really loud. Goes away in a few minutes. Any ideas?

 

2014 by 87k miles 4x4

 

post a sound clip??

 

here it is only. usually only on start up.

https://youtu.be/tYlY1cmKQvI

 

Anyone ?

 

Is the sound coming from under the truck? Inside the engine bay? if so where does it sounds like its coming from.

 

i can't really tell, but it's def from the engine. it's usually only a morning start up.

 

Could be a pulley on the front of the engine.

 

you know i switched 3 of the idler pulleys and put a new belt on. that's about when i started to notice it. however, i examined it and it looks fine.

 

racking my brain here....

 

My guess is the belt isnt tight enough.

 

bought the wrong size?

 

Just checked the tightness. It feels tight and doesn't seem to have over .5 inch looseness on top.

 

I just noticed that it stops if I push the clutch in slightly???

 

throw out bearing

 

Not that i have much of an idea of what im talking about, but that sounds the same as when i engage 4 Hi or 4 Low when its shifting between settings for a second. Just something i noticed.