NHTSA Complaint #11696122 — 2019 GMC SIERRA 1500

While towing a trailer on Highway 77 in northern Wisconsin, my 2019 GMC Sierra 1500 experienced a sudden engine failure. The dashboard lit up with alerts for the engine, transmission, ABS, and traction control. I safely pulled over in a 55 mph zone with narrow shoulders and heavy truck traffic due to nearby road construction. The truck lost all power, and I had to block the driving lane to transfer the trailer to another vehicle, creating a hazardous situation. There were no prior warnings or issues. The truck had regular service at independent shops, and I had checked and topped off the oil that morning. Lahti Towing & Service recovered the vehicle, changed the oil (no metal shavings), and replaced the camshaft sensor, but the truck still wouldn’t start. They then towed it to Rhinelander GMC, where a broken timing chain was diagnosed, requiring a full engine replacement. The vehicle is currently at Rhinelander GMC and available for inspection. I have photos of the dashboard alerts and data from the GM app documenting the incident.