The contact owns a 2023 GMC Sierra 1500. The contact stated while driving 35-50 MPH, the message ‘Service Engine Soon’ was displayed. Additionally, the power train warning light was illuminated. The vehicle was towed to the dealer, where it was diagnosed that the gear shift control module had failed and needed to be replaced; however, the part was not available. The vehicle was then towed to Parkway Chevrolet (25500 TX-249, Tomball, TX 77375; where the gear shift control module was replaced. Additionally, the contact stated while driving 35-40 MPH, the vehicle was sputtering. The contact was unaware of a warning light being illuminated. The vehicle was taken to the dealer, where it was diagnosed and determined that the TCM needed to be updated, and an unknown part needed to be installed for transmission cleaning. The vehicle was not repaired. The manufacturer was notified of the failure and referred the contact to the dealer for assistance. The failure mileage was approximately 21,000.