I have an 06 4x4. About a week ago I noticed a whining noise at all speeds. Best way I can describe it is it sounds like I have a set of very aggressive mud terrains on the truck. My first thought was wheel bearings. I jacked the truck up and there is a very slight amount of play in the passenger front bearing. I don't think it is enough to cause the bearing to whine like this though. The play could even be in the ball joints. I would say that it is less than 1\16th inch play. The sound changes with road speed, not engine speed. Does anybody have any ideas? Any help will be greatly appreciated. Thanks.

 

Have you checked out the u-joints on the front and rear drive shafts and the front axle behind the wheels? Oh and the carrier bearing?

 

Thanks for the reply. Driver side U joint is loose. Hopefully that is the problem. Never imagined a u joint would sound like that though. Well time to pull the hub I guess.

 

Mine was doin' the same thing a few months back and I was told that it was the passenger side u joint....turns out it was the passenger side hub assembly. I replaced that and all has been well ever since!