Product Details: Made with Expertise Built In™, OTR 10W-30 Synthetic Blend Diesel Engine Oil is an optimal heavy duty diesel engine oil, formulated to meet or exceed performance criteria of API CK-4, CJ-4, CI-4 PLUS, CI-4, and CH-4. Gain substantial engine durability improvements for long, reliable equipment life. This synthetic blend formula boasts enhanced resistance to oil breakdown, maintaining flow properties and maximizing drain interval potential. With excellent thermal and oxidation stability from the synthetic blend technology, safeguard your semi truck against the damaging effects of cold temperature start-ups. FleetPride is your First Click in Heavy Duty®.