Seems the reared is making a noise like vibration winding randomly

What is your question?

All I can tell is that the rear end is whining grinding sound, randomly actually I have put it up on ramps and I did notice a wet gritty substance up under the bed above the rear end area where the u joint hooks to the rear end. Like it splatter up and on the side of the gas tank, any suggestions that my idea would be right that the rear end seal may have went out?