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Keep Your Diesel Engine Humming with Royal Purple Duralec Ultra Diesel Engine Oil

Royal Purple’s Duralec® Ultra™ Diesel Engine Oil can handle what your truck’s engine dishes out. Duralec combines premium base oils with Royal Purple’s proprietary Synerlec additive technology, That creates a motor oil that optimizes engine performance and provides superior protection under heavy-duty use, especially for older, high-output diesel engines. The result is better performance and longer engine life.

Other Duralec Ultra Diesel Engine Oil benefits include:
• Up to four times more film strength and lubricity than similar oils
• Reduces deposits to keep engines clean
• Maximum wear protection–up to 33% better than CK-4 requirements
• Improved cold flow operation and startup protection
• Extended oil life–up to 40% better than CK-4 requirements
• Reduced oil consumption

Royal Purple Duralec Ultra Diesel Engine Oil is available in 10W30 and 15W40 formulations. It meets or exceeds the performance requirements for API Service CK-4, CJ-4, and CI-4+ diesel engine oils.

SEE ROYAL PURPLE’S DURALE ULTRA DIESEL ENGINE OIL AT SUMMIT RACING