NHTSA Closes Investigation into Corrosive GM Brake Lines By Stephen Elmer Apr 09 2015 Share this Article Tweet The National Highway Traffic Safety Administration (NHTSA) has closed an investigation into older GM pickups and SUVs without a recall. Continue Reading... Filed under: American Featured Articles GM Safety SUVs TrucksTags: Brake Line investigation, GM Brake LInes, GM truck brakes, NHTSA