1997 Ford Expedition wheels problems

While driving about 60 MPH driver heard a loud noise coming from the rear end of vehicle. Right afterwards the left rear wheel came off due to lugs:nuts: bolts shearing off. The problem was corrected by dealership. On april 24th, while driving right rear wheel came off, sending vehicle into a guardrail and ditch. The lugs: nuts and bolts sheared off.

While driving at 55 MPH, the consumer felt the vehicle wobble and thump to the ground. The consumer lost control of the vehicle which did a three hundred sixty degree turn on the highway. When the vehicle stopped spinning the consumer found that the right rear wheel had separated from the vehicle. The lug nuts had simply sheared off of the wheel. This problem has occurred twice on this vehicle. The only difference is on the second time one lug nut was saved from being sheared off.