— Nissan Altima rear lower control arms that failed due to corrosion caused the National Highway Traffic Safety Administration to open an investigation in 2018.
That investigation was expanded to more than 2 million Nissan vehicles in July 2019 and further expanded to include Nissan Maxima lower control arm corrosion.
It took more than six years, but NHTSA has closed its investigation without recommending a recall or additional actions by Nissan.
The original 2013-2018 Nissan Altima lower control arm investigation was opened after 91 complaints had been filed about rear lower control arm failures, especially in areas where road salt was used. Model year 2016-2018 Nissan Maxima vehicles were added later.
Nissan owners complained about problems steering and in some cases corroded lower control arms caused a loss of vehicle control. However, NHTSA knew Nissan had created a service campaign for 2013 Nissan Altimas in salt-belt states due to corrosion of the suspensions.
Nissan knew the rear lower control arm (lower spring link) could separate from the vehicle due to corrosion. Safety investigators determined the Nissan vehicles suffered from corroded bushings at one of the three mounting points of the control arms to the rear subframes.
Nissan owners typically first complained about noise and abnormal vibrations caused by the corrosion.
NHTSA also learned most lower control arm failures occurred after the vehicles had more than 113,000 miles on them. And NHTSA also determined Nissan's vehicle dynamic control system allowed a driver to maintain control if the bushing failed. Regulators found only one complaint of a low speed crash even after seven to 13 years of exposure to road salt.
According to NHTSA:
"Nissan implemented a design change in January of 2018 to improve the durability of the lower control arm. Affected vehicles have either been repaired with the countermeasure part under a customer satisfaction campaign or been provided a warranty extension from 3 years/36,000 miles to 10 year/unlimited mileage."
Safety regulators closed their Nissan corrosion investigation after not finding "a defect representing an unreasonable risk to motor vehicle safety involving corrosion of the subject rear lower control arm at this time." However, NHTSA may take additional actions if circumstances change.