Loud high-pitch squeal/whine in reverse

[Backwoodsram]

I have a 2018 Ram 2500, 6.7, deleted, 72xxx miles. The issue only happens in reverse. As soon as i shift in reverse a loud squeal/whine can be heard from under the truck. The noise is present with the vehicle moving or stationary with the breaks applied. The noise is louder with the brakes released and vehicle moving. I can't seem to pinpoint the source of the noise. It is not a standard gear whine tpye of noise. Any help is appriciated.

 

[Jim BB]

I suggest if you have a good reputable transmission shop near you to take it in and see what they have to say ! once they tell you i would go to a second on just to see if they come up with the same conclusion ! because it sounds like it is internal !
That's what i would be doing !

 

[Backwoodsram]

Some additional info. The nosie is now only present while moving. Also with the tcase in neutral, trans in park, rolling backwards produces the same noise so i think the trans can be rulled out. All ujoints are tight and brakes have plenty of life left in them, wheel hubs seem tight as well. I do have a bad HCU but its odd that its only in reverse if thats the culprit. Tomorrow ill try spinning the wheels one at a time with the motor off to se if I can reproduce the sound. The sound is also present at a very low speed and does get loud if i roll faster.