NHTSA Will Investigate 2015-2017 Ford F-150 Pickups Over Unexpected Downshifts

Ford F-150 pickups have experienced their fair share of issues with the six-speed automatic transmission in recent years, which prompted a recall back in 2019 after some owners of 2013 model year pickups experienced unintended transmission downshifts due to intermittent output speed sensor failure. Early last year, the National Highway Traffic Safety Administration (NHTSA) opened an investigation into 2014 Ford F-150 models for the same sort of problem, which it closed a few months later. Now, the NHTSA has opened another investigation into this matter.

This new investigation covers roughly 1,270,970 different 2015-2017 model year Ford F-150 pickups, and as was previously the case, pertains to an issue where those models can experience an unexpected transmission downshift without warning or driver input, oftentimes one accompanied by a temporary rear wheel lockup. Thus far, the NHTSA’s Office of Defects Investigation (ODI) has received 138 consumer complaints for these particular model years, which is what prompted the new investigation.

As one might imagine, this problem can cause rapid, unexpected deceleration, and in some cases, as previously mentioned, owners have reportedly experienced rear wheel lockup, which can cause a loss of vehicle control and increase the risk of a crash. As such, ODI has opened this Preliminary Evaluation (PE) to determine the scope and severity of the potential safety-related consequences.

In previously impacted F-150 pickups, Ford determined that the primary cause of this particular defect was related to the molded lead frame and the control assembly transmission main in select pickups, impacting 38 percent of those vehicles. Additionally, 35 percent of affected pickups needed repairs to the control assembly transmission main. Ultimately, a loss of signal between the transmission output shaft speed sensor and the powertrain control module was to blame – a problem that Ford was able to fix with a software update for the powertrain control module software.