I was driving on I75 North in Florida near Ocala (exit 358) traveling about 70mph when I approached slowing traffic. I attempted a slow and steady stop without slamming on the brakes. The emergency braking system engaged but the vehicle failed to stop and I was not able to completely floor the brakes. In an effort to avoid hitting the vehicle in front of me and causing a multiple car collision I swerved onto the grassy side of the road. Because the car would not stop completely my passenger front wheel made contact with a concrete ditch and my vehicle flipped over resulting in a total loss.