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

Federal regulators have opened an investigation into nearly 1.3 million Ford F-150 trucks after consumers complained the vehicle unexpectedly downshifted while traveling at high speeds, causing it to rapidly slow down and increasing the risk of a crash.

The National Highway Traffic Safety Administration has launched a probe into 1.3 million Ford F-150 trucks from model years 2015 to 2017 over reports of sudden gear downshifts that may cause the rear wheels to lock up.