Shell Helix HX7 motor oil uses special active cleansing agents to help engines operate efficiently. In studies by an independent agency, drivers felt that their cars were quieter after an oil change to Shell Helix HX7. The oil in a clean engine can flow quickly to where it is needed, so that the engine is better protected. The excellent cleaning power and shear and oxidation stability of Shell Helix HX7 mean that it goes on delivering its benefits throughout the oil change interval. Shell Helix HX7 is specifically formulated for fuel injection petrol engines that are fitted with catalytic converters and blow by gas recirculation. The oil meets vehicle manufacturers specifications and severe service applications, and has formulations for different fuels, engines and environmental conditions.