Traveling at high speed on major 5 lane highway. The engine shut off vehicle lost power went to neutral on shifter on its on would not shift . There was no warning no lights nothing that would have indicated a problem at all. Luckily my husband was able to get over 3 lanes and pull on shoulder which was very difficult and extremely dangerous in traffic. The vehicle would not start back up . There were 3 children and 2 adults in the vehicle at the time it was traveling 70mph and completely shut off we were almost struck by vehicles traveling at 70mph plus when trying to get vehicle to shoulder if we were unable to get this vehicle to shoulder this would have caused a multi vehicle pile up on major highway . We would have lost our lives and possibly others in other vehicles as well. Cadialic roadside assistance is picking up this vehicle and taking it to there closest dealership. This vehicle currently has 19,000 miles.