Washington — The National Highway Traffic Safety Administration is upgrading an investigation into nearly 253,000 Ford F-150s because of braking problems that are linked to at least seven crashes and one injury.
NHTSA said Tuesday it is opening an engineering analysis into 252,910 2011-12 F-150 pickups after opening a preliminary investigation in June. NHTSA says it has reports of 432 complaints and 6,476 warranty claims relating to failures of the electric brake vacuum assist pump with 3.5-liter EcoBoost engines.
The failure of the pump leads to “increased brake pedal effort at cold start and extended stopping distance while driving in traffic,” NHTSA says. In total, Ford has turned over records related to 1,851 warranty claims that cover either a hard brake pedal condition or reduced effectiveness – and 4,600 others for the part.
NHTSA said there was an injury in a vehicle struck in the rear by an F-150 with a failed part.
Ford said the F-150s under investigation utilize a traditional brake vacuum booster to provide power assist for braking. The electric brake vacuum pump, it said, is intended to maintain consistent brake pedal feel. It says the engine intake manifold is the primary source of vacuum for the booster and meets safety standards without the electric pump.
“We will cooperate with NHTSA on this investigation, as we always do,” Ford spokeswoman Kelli Felker said Tuesday.
Ford told NHTSA it doesn’t think a recall is necessary. The Dearborn automaker told NHTSA that conditions related to a change in brake pedal feel are “limited and temporary.”
Ford said the failure of the electric pump due to rust is progressive and gives warning with noise and vibration before there’s change in brake pedal feel.
The automaker turned over test data to NHTSA that looked at the impact on braking if the part is not working. The tests showed drivers would need two to three times usual braking forces to reach a stop when traveling 50 mph when the electric pump is disabled — and five to six times as much if there is a complete brake booster failure.
Opening an engineering analysis is a necessary step before NHTSA can formally demand an automaker recall vehicles.