Check the front driveshaft (propshaft). Mine makes a terrible noise (ask anyone that heard it in Moab). It sounds just like a bad cv and can cause vibration. My propshafts front cv is shot...I can move mine up and down (get your minds out of the gutter) about an inch. I have one in my garage waiting to go in. I got a trooper shaft from an auto salvage place for $70. I saw them online for anywhere from $50-300.