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Genuine GM parts have one of these marks:

Vehicle Care
California Proposition
65 WarningRear Wheel Drive Shaft Inner Joint and Boot Replacement Wheels
Special ToolsJ-35910Drive Axle Boot Clamp PliersNote:The inner Constant Velocity Joint is not serviced separately.If the CV joint is found to have excessive wear or damaged, replacethe wheel drive shaft as an assembly.Disassemble ProcedureRemove the wheel drive shaft. Refer toRear Wheel Drive Shaft ...