NHTSA Complaint #11696802 — 2025 CHEVROLET SUBURBAN 1500

Purchased the vehicle on April 7, 2025. On 7/15/25, the car had 6948 mi. and started running rough, had a loss of power, an odor from the engine, and then on the display: check engine, blinking green vehicle light, and a message stating that the car was lowering for stability control. Took the vehicle to the closest Chevrolet service. The service dept. determined that code found P0307 and P0300, cylinder seven had the most misfires above 500. After completing oil service, the vehicle began to click on the passenger side; however, it was not misfiring. They inspected and found potential lifter issue. Found ticking coming from cylinder 7 and verified misfires. Found 2 pushrods damaged. Heard noise coming from cylinder 4, removed valve cover, removed rocker arms, and found 1 pushrod damaged. They removed and replaced all lifters and 3 pushrods. They stated there was no more noise //after this repair. These repairs were completed on July 25, 2025. On 8/15/25 took back to service because it continued to run rough and made excessive noise and whistling when starting the vehicle. The dealer inspected and heard the noise, inspected the vehicle exhaust leak, checked exhaust manifolds, pipe connections, and determined there were no issues found. On 9/26/25 at 11,821 miles the car was making excessive noise, running rough, and was losing power. Drove home, and the vehicle was running rougher and losing power. No check engine lights or warnings were present. Drove home, and the vehicle was running rougher and losing power until it turned off. Towed in. Maintenance techs determined catastrophic engine failure, all bearings and engine rods seized. After this repair hen the catalytic converter failed. This car has been out of service due to engine failures for 43 days out of the 204 of ownership.