I am reporting a serious mechanical and safety issue with my 2019 GMC Sierra 1500 (5.3L engine). The truck began misfiring, running rough, and would frequently aœjumpa and shut off while driving a” creating an unsafe situation on the road. We attempted several repairs to resolve the issue: a¢Transmission flush a¢Replaced the intake manifold gasket a¢Replaced all eight fuel injectors a¢Inspected all ignition coils a¢Replaced faulty sensors The vehicle repeatedly showed a Cylinder 8 misfire, even after these repairs. Eventually, it was diagnosed that both the lifters and camshaft are bad, and the engine now needs a full replacement. This is extremely concerning because the truck has only about 47,000 miles on it. We brought it to the dealership in September 2024, while it was still under warranty, and told them it wasnat running right. The dealership said there was nothing wrong. Now that the warranty has expired, GM is refusing to help with any repairs. This appears to be a manufacturing defect that was not properly diagnosed while under warranty. Engine failure at such low mileage, especially with early warning signs and repeated diagnostic errors, should be investigated as a serious reliability and safety concern.