In a letter to Ford Motor Co. (NYSE: F) dated March 3, 2016, the National Highway Traffic Safety Administration (NHTSA) said that its Office of Defects Investigation has begun a preliminary evaluation of allegations of leaking brake fluid in 2013 and 2014 F-150 pickups with 3.5-liter engines. An estimated 420,000 trucks could be affected, more than a third of all F-150s sold in those model years.
The NHTSA said that it has received 33 reports alleging that the master cylinder on the trucks failed as a result of brake fluid leaking into the brake booster.
The agency wrote:
All of the complaints have involved trucks equipped with 3.5L engines. The complaints allege symptoms of brake pedal going to the floor with complete loss of brake effectiveness, brake warning lamp illumination, and/or low or empty master cylinder reservoir fluid level with no visible leakage. Four of the complaints allege that the alleged defect resulted in crashes.
The NHTSA is requesting information from Ford on the named pickups, along with all other F-150s equipped with the same brake master cylinder and brake booster assemblies. The investigators also seeking information on the reported symptoms.
The models in question pre-date the new aluminum-bodied F-150 pickups that Ford began selling in late 2014 as model year 2015 vehicles. But if the same parts were used on the new models, those too could be included in the investigation. The results of the investigation could lead to a recall, but that remains to be determined.
The letter requires Ford to produce the requested information by April 20, 2016.
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