It's clearly a drivetrain issue, if I move tires around I wont feel any difference. You would have to ride in it to understand. I have also noticed some times when I let out of the throttle it seems to go away immediately....but only sometimes..??
Could be ball joints. Death wobble in jeeps is from a bad ball joint, death wobble is felt when the jeep hits a certain mph. At that mph the ball joint starts "wobbling" around causing a vibration in the vehicle which is described as "death wobble," slowing down usually allows the ball joint to settle down and the vibration goes away.