2003 Excursion Brake pedal can be pushed to the floor
03 Excursion, 6.0. First experience was towing a 6000 lb boat. Brakes has seemed to be working fine. I needed to stop quickly for traffic and the boat trailer brakes did not work (trailer brakes are not electric). I pushed the pedal to the floor and kept rolling. I expected anti-lock brakes to kick in.
While trouble shooting, I can push the pedal down, it feels normal, pushed down hard and I can go to the floor. It feels like I am going over some relef setpoint. No brake line bulging issues. No system leaks. Checked the accumulators in the anti-lock brake block and they do not move. I flushed the system with new fluid, same results. I changed the master cylinder, same results. I do not have plugs to block the master cylinder or pressure gages to rule out the master cylinder. I did order a pressure gage kit, waiting on this.
History: Miles 101,100. Ford pads with about 10K miles. Even wear. Sloted and drilled rotors front and back. Normal braking is the normal experience. No leaks ever. 94,000 miles on original pads.