NHTSA broadens investigation into roughly 1.3 million Ford F-150 trucks over transmission concerns

The National Highway Traffic Safety Administration announced on Monday that it has expanded a safety investigation involving approximately 1.27 million Ford (F.N) F-150 pickup trucks after reports of unexpected downshifting accompanied by rear-wheel lockup.

According to NHTSA, the investigation includes vehicles from the 2015 through 2017 model years.

The expanded probe stems from a preliminary evaluation launched on March 21 last year, following consumer complaints about 2015–2017 Ford F-150 trucks equipped with the 6R80 transmission.

The U.S. auto safety agency said drivers reported that the vehicles could suddenly downshift without warning or driver action, resulting in abrupt slowing and, in certain cases, brief rear-wheel lockup or skidding, increasing the likelihood of an accident.

In its response to NHTSA’s request for information, Ford stated that the suspected defect in the 2015–2017 F-150 models is different from the problem that led to four safety recalls affecting 2011–2014 vehicles.
The automaker explained that those earlier recalls were linked to manufacturing defects in a component supplied by a third-party vendor, which caused a loss of speed sensor signals.

For the newer trucks, Ford said the issue may be related to electrical connections that degrade over time due to heat and vibration, potentially resulting in signal loss from a separate transmission sensor.

NHTSA’s Office of Defects Investigation noted that preliminary testing also revealed an additional safety concern, indicating that intermittent loss of the TRS signal could cause a vehicle backing up on an incline to shift into neutral and roll forward.
ODI said it has initiated an engineering analysis to carry out further testing and assess additional technical information.