NHTSA Complaint #11704718 — 2016 FORD F-150

While decelerating from approximately 80 mph to 65 mph under very light throttle, the transmission in my vehicle unexpectedly shifted into 1st gear for a brief moment at highway speed, without any driver command. This caused a sudden and severe deceleration event and created a loss-of-control safety risk, especially in traffic. The transmission immediately corrected itself, however after the event the vehicle avoided normal downshifts and remained in higher gears (5th and 6th), indicating abnormal transmission behavior following the incident. No warning lights or messages were displayed at the time of the event. The vehicle is a 2016 Ford F-150 5.0L equipped with a 6-speed automatic transmission (6R80). The vehicle has approximately 91,100 miles. The automatic transmission was serviced at approximately 80,000 miles, including fluid and filter replacement only. No transmission flush was performed. The vehicle has a new AGM battery, properly programmed to the vehicle. The vehicle was originally sold in Canada and is currently operated in the United States. The defect occurred during normal on-road driving and presents a serious safety concern due to the possibility of unintended wheel lock or loss of vehicle control at highway speeds.