The trucks engine completely shut down while going approximately 60 MPH while merging onto the highway. The trucks dash flashed multiple times, a ticking noise was heard, it put itself in neutral, and shut the engine off. All power was lost. I did still have brakes. Safety was a concern as there was a vehicle behind me entering the highway too. Cars to my left as well passing at highway speeds. Once I got the vehicle stopped on the shoulder of the highway it put itself in park. It would not restart. The vehicle was towed to a local GMC dealer. There were no warning lights of any kind that came on. No indication that there was a problem. A couple days later I was informed that the truck would need an entire new engine upon inspection. I was also told by the dealer that the truck had no oil at all in it. The engine consumed it internally by their evaluation.