I was just thinking about how good the brakes on my diesel were. The next day, they pretty much went to the floor. It has hydroboost, and the PS pump is fine, and it's not leaking fluid anywhere from any lines or seals. Anything different on a hydroboost system as far as why the pedal would start going to the floor? If I pump it, it seems to pump up and work up higher. Maybe it's just the master cylinder.