Ford Motor has recalled about 238,000 Explorers because of a defect that poses a risk of the SUVs rolling away if the parking brake is not engaged.

The affected models, from 2020 through 2022, have been discontinued.

“The rear axle horizontal mounting bolt may fracture and cause the drive shaft to disconnect,” the National Highway Traffic Safety Administration said in a letter to Ford on Thursday.

If the shaft, a rod that transfers power to the wheels and makes the vehicle move, disconnects, it could result in a loss of drive power or a vehicle rollaway if the parking brake is not applied, the letter said.

“Either of these scenarios can increase the risk of a crash,” wrote Alex Ansley, chief of the recall management division for National Highway Traffic Safety Administration.

Ford did not immediately respond to a request for comment Saturday.

Dealers will perform the necessary repairs free, the federal agency said.

Letters notifying owners of the recall are expected to be mailed Nov. 6. Drivers can also see if their vehicle has been recalled by entering their vehicle identification number or the year and model of the car on Ford’s website.

Ford said it was not aware of any accidents or injuries related to the defect, according to agency documents.

Vehicle recalls have become more common in the United States over the past two decades or so, according to a 2019 report by McKinsey & Co.

In 2016, the U.S. auto industry reached more than 1,000 vehicle recalls for the first time. In 2017, an average of about three vehicles were recalled for every vehicle sold, according to the report.

In 2022, Ford recalled 2.9 million vehicles, including 1.7 million Ford Escape SUVs, because of a potential defect that could let them move even with the gear shift seemingly in the park position.

In September, regulators flagged 52 million air bag inflators used by dozens of carmakers as being susceptible to rupture.

Since 2015, recalls typically have been related to air bags, according to the McKinsey report. However, as vehicles are made with more complex features, there has been an increase in recalls for software and electronic problems.

This article originally appeared in The New York Times.