Specially formulated performance oil for classic cars with 2001 and older engines. Formulated utilizing heat and shear stable polymers to maintain the optimum lubricating film and ring seal in hot running engines. Detergent / dispersant additive prevent deposits. Increased level of ZDDP (zinc+phosphorous) for extra protection. API Standards: API SJ / SG / SH / SF / CD High performance mineral oil specifically designed with classic muscle car engines in mind. It can also be used whenever a 20w50 oil is required or recommended.