2008 Escape, Sometimes after a hard braking event My brake peddle sinks to the floor and will not stop car until I pump the brakes several times. Scary and dangerous. Brake fluid level is fine. What is the problem

 

You didn't say whether any brake work was recently done.
If it was and all the air was not removed from the lines ,that could be a reason.
Also, a brake master cyl with worn internal cups could produce this problem.

 

2008, if no brake work was done it could also be old fluid in the system that has cavitation (produced air bubble in the fluid). During light "normal" braking it works. But, once you have hard "heavy" braking you have compressed the air and that is why the pedal goes to the floor and needs pumping to further compress the air. Which then leads to more cavitation in the fluid.

I agree with hanky also on the master cylinder worn cups "seals".

Suggest you try this, with car turned off, pump your brakes slow and evenly. After one or two pumps the peddle should stop. If you can pump the brakes and hold pressure on the peddle and it slowly goes to the floor, you could have master cylinder issues and that is your lose of brake pressure. If the peddle builds pressure and stops, it will not go any further, the cylinder is fine and look at bleeding the brake fluid. Your fluid is 11 years old and depending on your daily driving conditions, it could be as simple as change out the old fluid.

 

As stated above, you have air in the system, car isn't safe to drive that way. You didn't say what the mileage was, and if brake work had been done.