Help: Is it front differential or transfer case or driveshaft?

[jabstick420]

Happy holidays folks!!

2006 x5 4.4L e53

Recently had some road noise only with foot off the accelerator

Sounds like whirring tire noise

Unplugging the transfer case resolved the noise.

with wheels off the ground, spinning front tires does not reproduce any noises

So, is it fair to say it isn't the front diff?

At this point I'm looking to get ideas about how to isolate the problem.

No error codes on the cluster

I have had the trifecta in the past, but that usually would resolve after shutoff.

The sound is coming from the front driver side. Does not go away with wheels turning.

I have read that the output shaft splines strip on these rides. Not sure if these are the symptoms though

any thoughts would be greatly appreciated.

thanks!