Mobil Delvac PC-11 with mechanic changing oil

Understanding PC-11  

What is PC-11 all about? Which oil should I use? And how will it affect my fleet? If you still have questions about Proposed Category 11 (PC-11), then you’ve come to the right place. Learn everything you need to know about the latest diesel engine oil specification change here.

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  • The gold standard in engine oil

    Get the best tech for big trucks. Discover how CK-4 and FA-4 Mobil Delvac™ heavy-duty diesel engine oils outperform CJ-4 oils.

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  • CK-4 or FA-4?

    Find out which PC-11 oil is right for your trucks. See our OEM heavy-duty equipment chart for PC-11 product recommendations.

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  • The development of PC-11

    Get more of the story behind PC-11. Plus, learn how your fleet can make the switch to CK-4 and FA-4 oils.

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  • Ready for PC-11?

    Learn about the impact of the American Petroleum Institute’s latest diesel engine oil specification change on you, your trucks and your business.

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  • PC-11 Quiz

    How well do you know PC-11? Test your knowledge with our five-question quiz.

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  • PC-11 FAQs

    There are a lot of questions surrounding the latest diesel engine oil specification change. Get more of the details behind PC-11 here.

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  • Fleet performance

    Keep your trucks and your business going strong with the latest industry information, PC-11 oil recommendations and energy efficiency tips.

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  • Energy efficiency guide: Saving energy on the road

    Use this helpful energy efficiency guide to make sure that your fleet and business save energy and money on and off the road.

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