[Source unknown] Driveline Vibration Issue - Possible Root Cause
This guy ran over a mattress and decided to keep going. The ensuing jumble finally whipped around enough to put a tear in the gas tank, the subsequent lack of fuel is what finally brought this vehicle to its knees.
It had still managed to drive 30 more miles decently with a 60lb tangle wrapped around the driveshaft.
He complained that the vehicle had a "shimmy" when driving it high speeds.
This is what the dealership found..............