The NHTSA said software upgrades offered as part of two previous recalls did not address the rear axle bolts.
Ford recently notified the National Highway Traffic Safety Administration it is recalling more than 238,000 2020-2022 Explorer SUVs, because the rear axle horizontal mounting bolt may fracture, causing the driveshaft to disconnect.
Ford said the disconnected driveshaft could result in a loss of drive power or a vehicle rollaway if the parking brake is not applied. Either of these scenarios can increase the risk of a crash.
Dealers will replace the subframe bushing and rear axle bolt, as well as inspect the rear axle cover for damage near the bolt hole location and replace with a new cover if any damage is found. Repairs will be performed free of charge.
Owner notification letters are expected to be mailed Nov. 6. Owners may contact Ford customer service at 1-866-436-7332. Ford's number for this recall is 23S55.
Ford told NHTSA it has been informed of 396 reports of rear axle bolt failures. Fewer than 5% caused loss of power or led to a vehicle rollaway. The company said it s not aware of any crashes or injuries.
Ford previously filed two safety recalls on certain Explorers in April 2022 and March 2023. Its remedy was to add a software update which automatically applies the electronic service parking brake to keep the vehicle from rolling away in the event of a driveshaft failure.
However, there was no fix addressing the failed rear axle horizontal mounting bolt, which NHTSA said is the cause of the current issue.
NHTSA said it received two complaints alleging a loss of power and/or loss of transmission torque of the rear wheels in 2021 Explorers due to failure of the rear axle bolts. These vehicles were included in the previous recalls and fixed prior to the incidents.
NHTSA in June opened an investigation into the software remedy of the two previous recalls.