The F-150’s Single-Seal Master Cylinder Design is Doomed to Fail

Anyone out there having trouble slowing their truck down? There’s a lawsuit that says a change to the F-150’s master cylinder design is creating a dangerous braking situation.

All 2013-2018 Ford F-150s use master cylinders supplied by Hitachi, with the pistons fitted with just a single cup seal responsible for containing pressurized brake fluid. The lawsuit alleges this is unusual because pistons within master cylinders are usually fitted with two cup seals to ensure that fluid does not leak out of the master cylinders.

These single-seal master cylinders have already been recalled for the 2013 and 2014 model years. But instead of changing the design, Ford replaced the defective part with – I bet you can see where this is going – new defective parts.