I have a 2007 suburban 5.3l with 85k miles, I am getting a whine when i start to reach 34-40 mph, I think its coming from the front or center passenger side it sounds like when a front bearing goes out but if I am cursing and put the car in neutral it goes away, and you only hear it on acceleration. If i put the car in neutral and rev the engine while I'm driving no noise is present. Any ideas on what it could be?

 

Sounds like tranny. Have you checked or changed your fluid lately?
My 2003 made a similar sound and I was low just a pint.;

 

I have checked it looks clean and full

 

Any suggestions?