Doing a valvetrain rebuild or repair on your GM engine? This ACDelco valve lifter guide set is the genuine OEM part you need for a perfect fit. The set includes four guides, which are the small components that help keep the valve lifters (or pushrods, depending on the setup) properly aligned within the engine block. Using the correct factory part is essential for proper valvetrain geometry, smooth operation, and preventing wear or noise. This set replaces part numbers 12595365, 12551162, and 12569259. ACDelco is GM's original equipment parts brand, so you know this part is manufactured to the exact same specifications for fit, form, and function as the one that came in your vehicle from the factory. Whether you're a professional mechanic or a seasoned DIYer, starting with genuine parts like these ensures your repair is done right the first time and lasts. Always confirm this part number matches the one from your specific GM engine before purchasing.