Can't Find Squealing Sound

About a month ago my truck started making a squealing noise on startup but would go away after a couple seconds. The sound comes back when i'm driving slow, reversing or holding a turn. I replaced all of my belts and tensioners along with cleaned my steering res and installed a brand new steering pump. Just installed brand new wheel bearings as well. I can't figure out where the sound is coming from and would love some help. It is an extrmely loud and high pitched sound you can hear from far away.

Any ideas?

 

Check your engine harmonic balancer to see if the rubber on it is damaged. Good luck!

 

maybe the tension on the belts are a bit loose. Tighten them up a little.

 

I had this and it appears to be common. Slightly tighten up the alternator belt a little at a time. Be sure to loosen the lock bolt (big one up front) before tightening the tensioner (under the alternator.)

<TL;DR>

This drove me nuts for months. Replaced belt. Still happened. New belts. Still there. Presumed it was coming from the bearing, replaced alternator. Still there. I tightened the belts manually to spec, thought I had it right. Began tightening the alternator belt down, little by little. It's been gone for over a year.

Edit: if the squealing doesn't start to decrease at some point, it's something else, don't blow out your alternator bearing going too tight. Mine was particularly annoying, I wouldn't hear from it for months but when winter came it was reliably squeaky on startup so I managed to figure it out.

 

I'll give this a try, that makes the most sense to me. I've spent so much money replacing everything I thought it was that I've practically built myself a new truck

 

Update: after tensioning and replacing the belts, tensioners and idlers, steering pump, and wheel bearings, I gave up and took it to a shop. Their diagnosis you might ask? BUILT UP BRAKE DUST! hasn't made the sound since cleaning off the rotors. As embarrassing as it is to say that, at least I've now replaced most of the major wear parts on the truck

 

Ahhhh, the old brake dust - shotgun parts strategy. Well it's all refreshed!

 

do you have any pics of this BUILT UP BRAKE DUST that would make such a squeal upon startup and not even moving?
that i gotta see...

 

Agreed, inquiring minds want to know . . . how brake dust will affect a stationary truck. It would make sense if it's rolling but you said on startup. This is why I have trust issues with mechanics, maybe that's just what they told you. In a way it's like replacing transmission fluid makes your air conditioner work again.

 

I probably should've clarified, my alternator was making the sounds on startup so i fixed that prior to taking it into the shop.