Engine Oil Blended with a Partial Synthetic Base Stock Castrol Hypuron S is a high-performance partial synthetic diesel engine oil designed for heavy-duty engines. It provides good performance and protection for engines while enhancing component and equipment life, lowering maintenance costs and increasing profitability. The progressive formulation of Castrol Hypuron S meets the newest specifications from both Mack and Caterpillar. Formulated with low ash technology, it minimizes oil consumption, reduces piston deposit formation and increases oil film strength. BP Lubricants USA Inc.; 800/777-1466; www.castrol.com/us