More than one million Ford F-150 pickups have come under NHTSA scrutiny over a defect that has unsettled owners and could lead to a large-scale recall. The investigation involves models built between 2015 and 2017, equipped with 6R80 and 10R80 automatic transmissions that downshift unpredictably, without warning and without any input from the driver.
Ford F-150 under NHTSA investigation over dangerous transmission failures
The issue goes beyond annoyance and raises serious safety concerns. Nearly half of the owners interviewed reported at least one incident in which the rear wheels locked up during a sudden downshift, often accompanied by tire squeal and loss of traction. Some owners have stopped driving their trucks altogether because they no longer trust them. Complaints describe abrupt shifts into first or second gear, often recurring over time and making the vehicle feel unpredictable.
Investigators believe the root cause lies in degraded electrical connections within the transmission’s lead frame. Years of heat cycles and vibration weaken these connections, and as they deteriorate, the transmission range sensor begins to send incorrect signals. The gearbox then reacts erratically. NHTSA testing has shown that in some cases the transmission shifts directly into neutral, a particularly dangerous scenario when the vehicle sits on an incline.
The agency launched the investigation in March 2025 as a preliminary review. After more than 60 percent of the owners contacted by the Office of Defects Investigation confirmed the issue, NHTSA escalated the case to a full engineering analysis. The next phase includes component testing, vehicle evaluations, and in-depth assessments to determine whether investigators have identified the correct failure mechanism.
Ford stresses that this defect has no connection to the issues affecting 2011–2014 models, which the company recalled four times for separate problems. However, this case does not stand alone. In December, regulators opened another investigation into 2015–2017 Fiesta and 2015–2018 Focus models with the 1.0-liter engine and manual transmission, where a deteriorating timing belt clogs the oil pump and can lead to engine seizure. Whether and when official recalls will follow should become clear soon.
