NHTSA Complaint #11695085 — 2025 GMC YUKON

While traveling on the interstate at 10:30p, 6 hours into a highway trip, the vehicle shuttered violently and lost propulsion and powered systems control. We were traveling at 75 mph on cruise control and immediately had to take evasive action to avoid other vehicles traveling at highway speed as our vehicle rapidly decelerated to a stop. We were barely able to get to the shoulder of the highway before the vehicle came to a complete stop and all dashboard lights illuminated. There was no warning or indication of immanent failure or engine issue. The catastrophic engine failure did not allow for the attempted restart. After opening the engine bay we noted that the coolant reservoir was empty but there was no indication of any leaking fluid in the engine bay or on the ground. The coolant levels were normal at the trip start. We were stranded on the side of the busy interstate for approximately 2 hours awaiting OnStar assistance and were forced to exit the vehicle due to its proximity to the edge of an active lane, leaving us exposed and without any protection for 2 hours, in the middle of the night, until assistance arrived. It was a harrowing experience and we are lucky that we were not injured or killed. The vehicle could not be disengaged from park and had to be dragged onto the flatbed. It was taken to the local GMC dealership and left for diagnosis. It was determined that the #2 piston rod broke, smashed valves and sent metal into all engine systems. Bothe the engine and coolant system were replaced. In addition, the torque converter locked up and had to be removed during servicing. All parts were retained by GM.