The contact owns a 2021 Chevrolet Silverado 1500. The contact stated that while driving approximately 50 MPH, the engine started rumbling with the check engine, stability-trac, and the parking brake warning lights illuminated. The vehicle was taken to an independent mechanic who diagnosed a misfire in cylinder #1. The mechanic referred the contact to the dealer for assistance. The vehicle was taken to the dealer, who diagnosed that the lift valve had collapsed, and the right side of the block lifters needed to be replaced. The vehicle was not repaired. The manufacturer was informed of the failure and referred the contact to the dealer for assistance. The failure mileage was 80,000.