The contact owns a 2010 Ford F-150. The contact stated while driving approximately 75 MPH with the cruise control feature activated, the power train warning light illuminated. The contact stated that the transmission unexpectedly downshifted into first gear and the rear wheels locked up. The contact pulled over to the side of the road and restarted the vehicle. The contact stated that the vehicle was towed to the residence. The vehicle was diagnosed by a mobile mechanic with a handheld scanner and retrieved DTC: P0723. The vehicle was not repaired. The manufacturer was notified of the failure. The failure mileage was 152,000.