The contact owns a 2024 GMC Sierra 3500. The contact stated that while driving at various speeds, there was an abnormal knocking sound coming from the vehicle. There were no warning lights illuminated. The vehicle was taken to a local dealer where it was diagnosed; however, the cause of the failure was not yet determined. The contact was advised by the local dealer that the engine might need to be replaced. The vehicle was not repaired. The manufacturer was not made aware of the failure. The failure mileage was approximately 100,000.