Pulsating vibration above 60 ?

I had the same problem. Ended up being an endplay issue. I got everything up to temp with a drive then adjusted all the endplay completely out of the axle setup. I think .008” is spec. Fixed the problem. I see you are using the green bearing setup. What is your end play? If I recall no ability to add preload correct? I have a feeling mine was related to wear in the splines and when I loaded the center button in the center section everything sort of snugged up. Just my guess