You guys must think I’m crazy

So I have a low whining noise in my E 53 (2002). Seems to start at about 30-32, changes and gets louder about 37-39, changes again at 46-49, road noise kinda covers it up after that.

It’s not directional so I don’t think is a wheel bearing. I have some Sumitomo Touring LSH with about 15 K on them. I had these tires on another X 5 and they made a growl when decelerating to about 40. These tires were noisy also.

These sounds have manifested themselves gradually.

I guess I could get both differentials and the transfer case serviced and the not serviceable transmission.

I’m just throwing this out for advice, I may have to go to Idaho to see my new granddaughter soon.

Thanks
Any advice or experience would appreciated.

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