Checking to see if anyone else has had master cylinder issues with their F150. Here is what happened to me. I was traveling on the highway and approached a red light on a downhill slope. As I slowed, I noticed the brakes were soft, but then they went all the way to the floor. This required pumping the brakes to build pressure and hold the stop on the hill. The pedal again returned to the floor and began drifting forward, thankfully as the light turned green. I drove directly to the mechanic who diagnosed the master cylinder failure.

This shouldn't be something anyone should have to be concerned with on a 2017 model. (I have the 5.0 engine).

Purchased the 2017 F-150, Lariat FX4 certified pre-owned through a Ford dealership.

Less than 2500 miles later the brake pedal lost pressure as I was driving and went straight to the floor. I had to pump them like crazy and eventually it rolled to a stop. Turns out the the master cylinder had to be replaced?

Ford was able to fix it under my CPO extended warranty (I just had to pay $100 for the deductible but this is the 2nd major issue I've had and I've put less than 3k miles on this truck).

2017 Truck with ONLY 14,750 miles. Brake pedal was extremely spongy. Drove back home and looked in the engine cabin. I checked for fluids and they were "Max.". No issues. No fluids on floor. Had an appointment for Auto Repair. Turns out MC needed to be replaced. ONLY 14,750 miles. Could for the "Warranty Insurance" and have just hung me up. LOL. I'll be talking with FORD real soon.

Update from Sep 24, 2020: Just texted the agent and my 2017 F150 is NOT in the recall issue. Not happy with this...yet.

I was shocked at the number of F150's on this site with brake pedals suddenly going to the floor during all types of stopping situations. The problem seems to span 2016-17 models regardless of engine.

It started yesterday with a freeway off-ramp failure and put me in the middle of a relatively safe intersection today... NO BRAKES. I've seen master cylinders replaced to dealers stating that is the normal operation. That last part is pretty lame... Brake pedal going to the floor? The brake initially seems to work and then the pedal sinks slowly to the floor with NO braking force at that point. At a full stop in park, I can repeat the failure. Touch the brake and it appears to be OK. Quickly touch it again and it immediately sinks to the floor.

Apparently knowledgeable dealer indicated that there may be an ABS solenoid sticking cycling brake fluid back to the reservoir instead of being applied to brake pressure. This sounded much more logical than replacing the master cylinder unless the ABS is integrated into it in some manner. After all this time, why hasn't Ford issued a service bulletin. Are they waiting for exploding gas tanks on Pinto's???

My brake pedal issue first happened around 7000 miles. While sitting at a light my pedal slowly sank all the way to the floor. I figured it was new and a bubble or something was in the system so i pumped the brakes and went on. a week later it happened again at a stop light. this time I took it to the dealer. They had it for a day and told me they could not find anything wrong with it and that cars have adaptive braking now and this was normal. I left extremely frustrated mainly because of the BS they feed me like i was stupid or something. I was not surprised that the brake problem did not happen to them since it only happens every now and then. So i decided to try to drive it until i can figure out what causes it to happen. Fast forward and I now have 12,000 miles on my truck. The brake pedal goes to the floor at least once or twice a day maybe more. I still have not figured out a trigger that causes this to happen though. However there are three symptoms to this problem. one being my brake pedal is very inconsistent. (it is firm some days and mushy others), The brake pedal will fade to the floor after coming to a complete stop. and finally the worse one is when your approaching a stop and the pedal starts fading but your trying to stop so you end up chasing your brake pedal to the floor. I plan on taking my truck in soon (to a different dealer) and hopefully it will do this to whoever is driving it.

At about 11500 miles I noticed that the brakes on my F150 begun to sink to the floorboard level as I approached stops. I took it to the dealer to have it checked out.i was told that the brakes were totally checked and were “operating normal at this time”. I was also told that there had been several other owners in for the same symptoms but there had been no problems.

Well, I’ve been driving it around town with the same problem of coming to a stop and feeling like the brakes are going to give out. I don’t understand how all of a sudden after driving this vehicle for over 11,000 miles, and to start having braking issues that it can be normal. If there was ever a case for a fix or a recall now is the time before a serious accident happens.

I can tell you that after buying this on the recommendation of my son who has a 250 KR PACKAGE we won’t be buying anymore Ford products. Especially after seeing all the braking issues Ford has on this web site.

Mike-Tulsa

I was driving my 2017 F150 with less than 7,000 miles and stopped at a stop sign and all the sudden the brake pedal went to the floor. I pumped at a few times and the brake pressure came back up. After shutting vehicle off and then starting I had to pump the brakes to get pressure. later that day I went out and at a light the pedal went to the floor while stopping. I took truck in next day and they replaced the master cylinder. i can not believe this with a vehicle with less than 7,000 miles. This is my 4th F150 and I have never experienced this even after over 100K miles on them,