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Find the right oil
Get the best tech for big trucks. Discover how API CK-4 and FA-4 Mobil Delvac™ heavy-duty diesel engine oils outperform CJ-4 oils.
Find out which oil is right for your trucks. See our OEM heavy-duty equipment chart for CK-4 and FA-4 product recommendations.
Get more of the story behind CK-4 and FA-4 oils. Plus, learn how your fleet can make the switch to these advanced oils.