The contact owns a 2015 GMC Sierra 1500. The contact stated while driving 30-35 MPH in third and fourth gears, the vehicle vibrated and shuddered significantly. The check engine warning light was illuminated. The contact stated that upon shifting out of third and fourth gear, the vehicle responded as needed. The contact stated that the failure progressively worsened while driving in third and fourth gear. The vehicle was taken to Wyatt’s Automotive Repair, where it was diagnosed with transmission failure. The contact was informed that the transmission needed to be replaced. The vehicle was repaired. The dealer and the manufacturer were not notified of the failure. The failure mileage was approximately 97,000.