The contact owns a 2017 Ford F-150. The contact stated that while driving 65 MPH and accelerating to overtake another vehicle, the transmission unexpectedly downshifted, and the vehicle jerked hard and then shut off. The contact was able to coast to the side of the road, shift to park, and restart the vehicle. While driving 35 MPH, the rear wheels locked up momentarily and then continued moving. There were no warning lights illuminated. The vehicle was taken to a local dealer, who was unable to determine the cause of the failure. The vehicle was not diagnosed or repaired. The contact called an independent mechanic to schedule an appointment. The manufacturer was not contacted. The failure mileage was approximately 72,000. The VIN was not available.