NHTSA Complaint #11676400 — 2010 FORD F-150

Leaving my driveway today, the 2010 Ford F-150 suddenly indicated a brake fluid level low message and the brake warning indicator turned on. The brake pedal, which was firm about a minute before, suddenly depressed to floor and the truck was stopped only with great difficulty. The sudden change in braking performance would probably have caused an accident if I had been driving in traffic. I took the truck to a mechanic who refilled the master cylinder and bled the brakes. I left the mechanic and pulled out. The brakes were fine leaving the lot. About 1/4 mile later, the brake warning came on and the brakes became spongy. I immediately returned to the mechanic and was informed that the brake master cylinder was draining into the booster. Apparently this is a recall item on later F-150s but it does not appear to include the 2010.