I just had my trans replaced for exactly what you're describing. Started at 700 miles on a 2016. Ford originally approved a new output shaft bearing, but upon disassembly there was metal in the trans so they approved a replacement. This one shifts perfectly and I get no whine at 65mph/partial throttle, only the normal gear noise in 5th and 6th. Bring it to your dealer, the whine only gets louder and more annoying.