US probes complaints that Ford pickups can downshift without warning, increasing the risk of a crash

U.S. auto safety regulators are investigating complaints that more than 540,000 Ford pickup trucks can abruptly downshift to a lower gear and increase the risk of a crash. The National Highway Traffic Safety Administration says in documents posted on its website Friday that it opened the investigation this week after receiving 86 consumer complaints about the problem with the trucks' automatic transmissions. Documents say the probe covers F-150s from the 2014 model year. The agency is looking into whether those trucks should have been included in previous recalls for the problem. The complaints allege that the trucks can suddenly shift to a lower gear without warning. Often, the rear wheels locked up. Ford says it’s working with NHTSA to support the investigation.