The contact owns a 2017 Ford F-150. The contact stated while driving at an undisclosed speed, the transmission unintendedly downshifted. No further information was available. The vehicle was taken to an unknown dealer, where it was diagnosed that there were metal shavings inside the transmission, causing the transmission failure. The contact was informed that the transmission needed to be replaced. The vehicle was repaired; however, the failure persisted. The vehicle was not repaired. The manufacturer was not made aware of the failure. The failure mileage was approximately 12,000.