It appears that the torsion bar that works as the rear stabilizer bar, inside the rear axle is cracked at the left axle plate weld. Noise is a metallic "cracking" when the rear wheels are going opposite directions: one raising and the other going down. I removed the rear axle by myself, and will take it to a qualified welder to reweld the torsion stabilizer bar, because the weldong cannot be performed with the rear disc brakes on. The stub axles need to be removed in order to make room to the welding pistol to access the weld area.
back end sounds like rattling a can when going over any bump, cracks or uneven pavement.
solution replace rear axle/torque tube
could'nt figure what the problem was un