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The American Petroleum Institute (API) has approved two new diesel engine oil standards, API Service Categories CK-4 and FA-4. The oil and additive industries and diesel-engine manufacturers have worked together over many years to develop these specifications. Now we’re getting the word out about the new diesel oil categories to help you make the switch.

API’s development of engine oil standards is nothing new. We’ve been publishing them since the 1940s. Normally, new engine oil standards are developed to protect new and current engine technologies, meet new government regulations, and ensure tests are in place to measure engine oil performance. All of these factors figured into the development of API CK-4 and FA-4. What’s different about the development is API’s introduction of two diesel engine oil standards at the same time. We haven’t done that since 1994.

Oil Category Guide

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.

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