Formulated with high viscosity-index, paraffinic base stocks and specialty performance additives, HELIOS  25W-60 CH-4/SL HEAVY DUTY MOTOR OIL exceeds the American Petroleum Institute’s specifications per the CH-4 category. API service class CH-4 is recommended for high-speed, four-stroke diesel engines designed to meet 1998 exhaust emission standards.CH-4 oils are specifically compounded for use with diesel fuels ranging in sulfur content up to 0.5% weight. API Service Class SL was introduced in 2004 for the regular service of gasoline automotive engines. This oil can be used in place of CF, CF-2, CD-II, CD, CC, and SJ Oils. HELIOS 25W-60 CH-4/SL HEAVY DUTY MOTOR OIL is multi-grade engine oil for use in engines in all seasons.