Originally Posted by mattw1992
Just an update to this issue. I have noticed it happens when in 8th Gear or overdrive and as soon as i put it into neutral or accelerate or flick in back into 7 using the paddles the noise goes away instantly.
You don't mention which of the 8 speeds you have [there are 2, one for the v8/diesel and one for the v6]. Still, it is new, and it should not be making that noise.
I would have guessed a cracked connector causing a whistle under high vacuum until you mentioned you can nuke it by changing gears. That sounds more like you want that transmission checked quickly.