Owners/service Manual problems of the 2007 Jeep Grand Cherokee

I was driving on route 50 going 65mph. This vehicle is a quad 4x4 automatic / stick shift manual, which was in my favor. When I realized the vehicle was shutting down I had to think quickly what my next steps would be. I started to get over to the right side of the road and brake, because the vehicle was shutting down the power brakes where going out and I could not brake completely. The vehicle was still moving and I was about 200 yards away from my exit and the side of the road was winding around toward the off ramp and getting smaller for me to drive on. I realized that I was not able stop the vehicle by using the floor brake then the fear factor set in. In my mind the only thing I can do is pull the stick shift handbrake and quickly put the vehicle in park then I was able to get control and safely stop the vehicle. This ordeal happened at 4:20pm yesterday and by the time we towed the vehicle back to the dealership and tried to explain to the general sales manager, si faige, on site at darcars in new carrollton, MD what all transpired on the road in the unsafe vehicle that they sold us, he didn¿t want to hear any of it.