Regulators received over 100 consumer complaints about transmission shifting to a lower gear without warning. The investigation affects some Ford F-150s.

The problem could affect nearly 1.3 million F-150 trucks. Ford is cooperating with the investigation as the NHTSA determines the scope and severity of the potential issue.

Certain Ford F-150 pickup trucks are being recalled in Canada and the U.S. because transmission can unexpectedly downshift into first gear when vehicles are being driven regardless of speed.