For reference, this was the slack in my 2011 2.4 , that was enough to bust up the front guide and set a code P0016. This chain kit was from Evergreen, the parts all had GM part numbers, the bags for the chains also had GM numbers in the label. This was just 20,000 miles of normal driving. No need to look any further then just removing the valve cover! Order the parts , start tearing the engine down! Don’t order cheap junk off flea bay!