2008 F150 HD Payload package with 5.4L and 4spd auto, 61,000 miles.

Recently developed a whining sound coming from the transmission or somewhere else in the drivetrain. Does not sound like rear axle because it changes pitch with the change of gears. I proved this by disengaging OD while driving and the whine was higher pitched once the transmission down shifted. I did some other research and found a reference to the #9 bearing going bad in a 4R75 trasnmission in a Crown Victoria. Anyone else heard or seen of this failure. I am going to fight for any repair to be covered by the powertrain warranty even though it just clicked 61,000. The dealer has done ALL maintenance on this truck since it was new (following severe duty recommendations). Thanks.