Whistling when changing gears

[Detfruit]

So I'm just about to hit 100k on my PIU, and I've noticed a whistling noise that appears right when I hit higher rpms before it upshifts. It's really only noticible when in lower gears.

I'm at work and won't be able to get under the car until tomorrow afternoon, but it's driving me crazy! Off the top of my head I am going to go over the following when I have the chance.

-PTU
-exhaust leak
-transmission lines

If there's anything else you all think I should check, please lemme know! I've got an appointment at the dealership tomorrow morning for some recalls for the power train reprogramming but Id rather not pay the cost that they'd hit me with for all the diagnostics..

 

[peterk9]

Is it a constant noise or does it come and go?

Peter

 

[Detfruit]

Is it a constant noise or does it come and go?

Peter

Seems like a constant noise that gets louder before upshifts, however if I drive it harder it seems to go away until it upshifts. It is non-existent at +45mph.

Unfortunate Update: dealership called back, PTU is leaking and they are advising replacement. 2200$.

Another less unfortunate update: Decided to refuse and get a second opinion, got home, got under it and....it's not leaking. Huh. Could it be leaking into the transmission? I doubt they would be able to see that without digging alittle further than they did from what my dashcam saw.. checked it on a hunch after seeing the PTU for myself. Spent about 3 minutes on the lift. Service advisor called me about 2 hours before they lifted it up. Did I just almost get played?