engine noise
Have a 2010 Sierra
I have 2010 Sierra Z71 with 198,000 plus. Started making loud lifter type noise. Repaired by ASE certified mechanic. Found rollers with damaged metal. Put in new rollers and lifters, new cam, new oil pump, new oil change and filter, cleaned out any remnant metal, deleted fuel management system. After repairs, drove slowly to break in new parts. In less than 1,000 miles loud noises returned. Oil ok when checked. What should I do next?