I've had three occasions recently where the brake pedal on my 04 F150 Screw has gone nearly to the floor. It will pump back up but the pressure goes away very quickly and several pumps are required to get enough pressure to stop. Took it to the dealer last week and they could not repeat the condition but checked the entire system and found no problems. Just yesterday it happened to me again. After turning the ignition off and letting it sit for about 15 minutes it worked fine. Anybody else experienced anything like this?

 

First thing I would do, if it is under warranty, is take it to another local dealer.

It sounds like one of two things.
1 Air in the system (leak somewhere) . The inconsistant part is a pain. Maybe in the ABS if so equipped. They are a pain to bleed.
2 The mastercylinder is leaking internally.

Let us know what you find and have a good day with family and friends till then.

 

Your master cylinder is shot.

 

I agree, your master is shot. The body is made of aluminum with a special coating on the inside of the cylinder to allow for a smooth surface and a good seal around the piston. Sometimes that coating doesn't take properly and begins to flake off, which exposes the rough casting. The O-rings around the piston can't seal as well (or at all), the result is your problem.

Go to a different dealer and get that master replaced before something happens!

 

Saw this thread, mine are doing the same, 2004 F-150 XLT supercab, 1400 miles. I was going to contact the dealer to see if they could do a powerbleed but maybe it needs a new master cylinder?

 

The brakes on my 2005 SC were pretty soft & mushy since I picked it up and then yesterday the pedal went to the floor 3 times in row. There was some stopping power, and they pumped up but I was pretty upset.

The dealer had it all day and said "Nothing wrong. Normal". I spent some 45-minutes with him this evening and every - and I mean every new F-150 we could get to did the same. With little effort the brake pedal will go to the floor.

Freaky to me - normal to Ford! My previous 3 F-150's never did this, and my other Fords do not and yet this is now normal!

 

Sounds pretty bad to me.. do I see a recall of some sort in the future.

 

If this is normal to these knuckleheads, the fix will be to lower the floor.