This listing is for all sixteen (16) compatible with 2005-16 GM family models using the 4.8L 5.3L 6.0L 6.2L V-8 engine with Active Fuel Management (AFM). 

AFM lifters fail due to a faulty VLOM (valley cover) from GM - Updated VLOM# 12571609 from GM must be installed with new lifter to prevent future failures.

NO Warranty on lifters.