So I am a new jeep owner and love the jeep so far. I have 1 issue with it:

the WK I bought whistles on the highway. the trouble im having with it is....it's only at certain speeds, 60-68ish, not above or below. it only does it when I'm on the gas...

it sounds like it's coming from the rear of the car but it's difficult to tell. I just taped up the top and rear creases, as well as the front window crease to see if the whistle was being caused by air somewhere, such as the commander windshield issues. the tape didn't solve it.

i've researched a bit, and think maybe it's a pinion bearing, but wanted to see if anyone could listen to the video I attached in the youtube link and tell me what they thought?

i suppose it could be a vacuum leak, but I feel like i'd hear it from the front of the car and while at idle, revving too. which I don't.

could it be a tire causing the noise?? i feel like if i had a weird tire, it would make the noise consistently, not just while on the throttle.

youtube link:

 

I agree with you. I think it's a pinion bearing. IDK what you have for an axle, but the D35's are noted for this.