Active Fuel Management system is starving the lifters of lubrication. Push rod got snapped in half and lifters needed to be replaced. Then the headers had to be fixed because of all of this. With a complete repair done, the push rod has again malfunctioned one month after the new one was put in. My certified mechanic has informed me Im going to continue to have an issue while GM isnt concerned with addressing the issue of the AFM system.