PFD66

I have had my truck at the dealer for some brake problems. About 4 months ago, I couldn't stop at slow speed, had a hard brake pedal, but kept inching forward, was able to put in neutral, and turn in time not to drive into the side of another truck. Brought it in, and they replaced a wheel speed sensor, and reprogrammed the abs.
A week ago, had a similar problem, but pedal was softer, and could hear the abs system working, almost plowed into my trailer that time. Took it in and they replaced the brake booster.
Brake have felt different since,a bit soft. Yesterday was at the store, and still had my foot on the brake pedal after pulling into a parking spot, the pedal started to slowly drop, all the way to floor. ( still had foot on it, but not standing on the brakes).
Dropped off at dealer again, got call today they couldn't find anything, and they said they tried another truck on the lot and that one was the same, as in they could put the pedal to floor. Never had it do that before.
Anyone have their pedal bottom out on the floorboard with their foot on it?

PaBEAR

Never. Something is seriously wrong. Take it to another dealer I'd you need to before something bad happens.

CoreyMS

Yeah, it will bottom out if you put force on it, but mine has never crept.

BadAlBell

Sounds like what happened to my 2001 suburban
There is a TSB on it
ABS sensors get dirty and it wont stop
KInda spooky

Watt-maker

Sounds like the master cylinder is bypassing internally. I have seen a few cars do this. Take it to another dealer. If they all did it we would be dealing with a recall.

PFD66

Stopped into dealer, they had a different tech look and it with me, and first thing he mentioned was a possible internal Master cylinder leak, and they have ordered a master cylinder for it, will be done Monday. And a Lincoln MKS to drive over the weekend.

Will update when I get it back.