need help dxing high pitch hum

[nerdofalltrades]

I need some help diagnosing a high pitch hum. it increases and decreases with speed, nothing with while in park and revving up the rpms. it kind of sounds like tire noise but it's not. it's not engine noise it sound more drive train related. 2000 sr5 4x4 with 193000

any help would be appreciated!