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American Petroleum Institute

Engine Oil Licensing and Certification System
1220 L Street, NW
Washington, DC 20005-4070
Toll-free in the U.S. & Canada: 877-562-5187
Local & International: (+1) 202-682-8041

Media Contacts

Contact Diesel Oil Matters for information requests or to arrange meetings with API personnel.

Engine Oil Toolkit

Whether you’re looking for information on the new oil standards, seeking guidance on switching your fleet to these next-generation oils, or searching for practical recommendations to bring CK-4 and FA-4 oils into your shop, you’ll find answers in the toolkit.

Get your Toolkit