Hello,
I have a 2006 Chevy Silverado 1500 Z71. Recently I have notice a pretty loud whining noise coming from under the hood and seems like it is getting worse. I dont believe it is the power steering. And I have had idler and tension pulleys go bad before but this sounds a bit different. I was wondering if anyone has anyother ideas of what it could be. Tomorrow me and my buddy are going to try to figure it out and was just hoping I could get some more ideas of what to look for. Any ideas would be appreciated.

 

Perhaps the alternator?

 

WHines can be a lot of things... Streteched Belt, Bad Bearing, bad accessory...

Does it leak anything? (could be a water pump bearing)
Do you have any blow by? (oil in your exuast)
Do you have a Tick or Knock with it? (bad bearings in the bottom end)

As Maniac said, could be your alternator? They have 3 - 5 bearings in side of them... one goes bad, puts pressure on the others, whines/squeals...

Had to diagnose without hearing/seeing

Matt