Understanding API CK-4 and FA-4 engine oils

The gold standard in engine oil

Mobil Delvac™ diesel engine oils can help you reach your business goals. These API CK-4 and FA-4 oils outperform CJ-4 oils; they are designed to help increase oil drain intervals (ODIs) and boost uptime. Learn more about Mobil Delvac heavy-duty diesel engine oils below. If you can’t find what you need here, please reach out to authorized distributors for more CK-4 and FA-4 information.

Improved performance with Mobil Delvac™ heavy-duty diesel engine oils

We compared our CK-4 Mobil Delvac™ 1300 Super engine oils to our CJ-4 Mobil Delvac 1300 Super engine oils. The test results showed that the CK-4 oils provided 20 percent improved wear protection,* 50 percent improved oxidation resistance† and 80 percent improved high-temperature viscosity control.† In addition, the FA-4 oils showed enhanced fuel economy potential (for FA-4 products only) and protection beyond original equipment manufacturer (OEM) ODIs.

Comparison chart of CK-4 and FA-4 motor oil products for Mobil Delvac

Mobil Delvac heavy-duty diesel engine oils

*Based on a comparison of Cummins ISM and Mack T-12 engine test results.
†Based on a comparison of Volvo T-13 test results.
‡Compared to a 15W-40 conventional engine oil. Actual savings are dependent upon vehicle/engine type, outside temperature, driving conditions and your current engine oil viscosity.
§Average OEM ODI recommendation based on recommended oil drain intervals from major U.S. engine manufacturers using API CJ-4 oils for a variety of service severity levels and engine models. Average OEM ODI API CJ-4 recommendation to substantiate multiplier claims is 31,750 miles. Results may vary based on vehicle/engine condition, driving and environmental conditions. Consult OEM or ExxonMobil before implementing extended ODIs, especially if the equipment/vehicle is under the OEM’s warranty.
**Based on measured viscosity increase in the Volvo T-13 test.


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