After four complaints, the National Highway Traffic Safety Administration (NHTSA) has opened an investigation into 2010 Ford Fusion vehicles that allegedly had one or more wheel stud fractures. Three of the complaints came from a fleet of vehicles, but different drivers were assigned to each vehicle. All four of the complaints had low mileage and the wheels had never been serviced prior to the problem. All vehicles were equipped with steel wheels with decorative wheel covers and are attached on five wheel studs. If the wheel studs should fracture and break off, it could result in loss of wheel and vehicle control.