Whining noise on deceleration (1 Viewer)

[ceebs87BJ]

Trying to find the source of a high pitched whining/whirling noise whenever I am not on the gas. It happens as soon as the clutch is pressed or on deceleration. I recently lubed the drivetrain so I suspected the rear driveshaft was too full of grease and it was effecting the pinion preload in the rear diff. I pulled the rear driveshaft and drove around the block in 4x4 (FWD) and the noise is still there. Could it be something in the transfer case? Any ideas? Truck is BJ70 with H55f

 

[roscoFJ73]

See if you can recreate the noise with the t/case in neutral.