Engineered for greater protection against thermal breakdown. Today's harder working engines operate at extremely high component temperatures causing thermal breakdown. Castrol Heavy Duty SAE 30: Contains unique anti-oxidants, detergents, dispersants and vanish inhibitors that help prevent ring-sticking and build-up of harmful engine deposits. Provide maximum engine wear protection in warm climates. Exceeds: API Service SJ/SH. Exceeds all passenger car and light truck manufacturers' warranty requirements for the protection of gasoline and turbocharged engines where API SJ or SH is recommended. Castrol, the technology leader, continually improves performance through product innovation. This may result in color/odor variations from time to time. SAE 30: A premium mono-grade oil, providing excellent wear protection.