Engine Oil Leaking problems of the 2008 Ford Fusion

I bought a 2008 Ford Fusion. I have under 100,000 miles and the oil pan came off and blew my motor. I am very disappointed and angry about this situation. I took very good care of the car. Got oil changes and checked the oil weekly. There was no oil leaks whatsoever. When I contacted Ford I was greeted with rudeness and a don't care attitude. Is this how you treat your customers on a daily basis? there was no warning or indication that the motor was gonna blow up. I was driving 50 mph when the car motor blew out. Luckily I wasn't hurt or anyone else. Please contact me that you received this information.

On Monday September 16, 2013 I began to hear knocking from my engine on my way home from work. When I arrived home, I checked the oil dipstick and it was dry. I put two quarts of oil in it and the knocking persisted. On Tuesday I took the vehicle in to a local mechanic to tell me what the knocking was. He checked the dipstick and it was again dry and told me I needed a new engine. I then had the vehicle towed to the Ford dealership where I purchased it. They told me the oil drain plug was only held in be three threads and that's why there was no oil in the car, thus causing the engine failure. At no time did any warning lights illuminate on the dashboard. The dealership doesn't want to cover the repair under my extended warranty because they say a "negligent repair" caused the engine failure. However, no one has an explanation as to why no warning lights ever alerted me that there may be a problem. The repair shop that changed the oil last says the oil was drained from the car quickly, and there was not a gradual leak because the "bottom of the vehicle is dry. " assuming this was vandalism, no warning lights ever illuminated in the car saying that the oil was low or empty, and the check engine light never illuminated either. I'm still trying to get the engine repair paid for.