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Genuine GM parts have one of these marks:

Vehicle Care
California Proposition
65 WarningPrimary Camshaft Intermediate Drive Chain Tensioner Replacement Valvetrain Camshaft
Removal ProcedureRemove the engine front cover. Refer toEngine Front Cover Replacement.Note:If the entire camshaft timing system is not inStage-2,Timing Chain Alignment Diagram, mark the timing chain andsprockets in order to ensure proper reassembly.Remove the primary camshaft drive chain tensioner. ...