The recall affects only cars with 17-inch steel wheels built from April, 2009 through April 30, 2009, and from Dec. 1, 2009 through Nov. 13, 2010.

Federal regulators say that bolts holding the wheels on can fracture, causing a vibration. If the vibration is ignored, the wheels can separate from the car.

Ford says it’s not aware of any crashes or injuries caused by the problem.

Dealers will replace the lug nuts on all four wheels and check the rear disc brake surface. The recall is expected to begin around Jan. 24.