Henry JR

Hello, I am new here and I hope that I am doing this right. I have a 2018 SuperCab 4x with the 5.0 V8 with 76K. I had taken this in last November and the dealer basically rebuilt the transmission as I was experiencing hard up and down shift issues along with other problems. This was done under extended warranty, thankfully as the bill was 4900.00 plus. Just a few days ago I noticed a whine that is very similar to the gear whine in low range when reaching a speed in excess of low range. This whine occurs only in 4th thru 6th. If I drive in manual mode and change the gears myself the sound goes away in 7th and diminishes considerably in 3rd.
So my question is, have any other owners of this year/power train combo experienced this? It doesn’t seem normal but it may be.
Any help would be appreciated