Whistling sound from under the truck???

Hi everyone,my name is John.im new here and I have a strange loud whistle coming from the drivetrain after acceleration and I am giving just enough gas to maintain speed. Any body have this problem?

 

John, I realize your post was from March and that you have probably figured out the solution to your problem but, if not, check the center support bearing on your driveshaft. Mine is doing the same thing and I think that's the problem. Good luck.