2. Do engine manufacturers recommend use of API CJ-4 oils to protect 2007
emission-controlled engines?
Yes, API CJ-4 oils, used in engines running on ultra-low sulfur diesel (ULSD) fuel, are critical for the durability and performance of 2007 and newer engines that utilize advanced emission control technologies. These oils have been subject to the most severe qualification testing requirements of any API engine lubricant category. API CJ-4 oils are designed to meet the expectations of the engine manufacturer and the customer in terms of both engine performance and maintenance intervals.
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3. How does the performance of API CJ-4 oils differ from previous categories
like API CI-4 or API CI-4 PLUS?
API CJ-4 oils have additive systems specially designed to improve the protection of both the engine power system and advanced emissions control systems like DPFs. Use of these new oils will help maintain the life of the emission control system as required for regulatory compliance. API CJ-4 oils are formulated for improved wear protection, deposit and oil consumption control, soot-related viscosity control, prevention of viscosity loss from shearing, used oil low-temperature pumpability, and protection from thermal and oxidative breakdown when compared to previous API performance categories.
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4. How does the use of API CJ-4 oils impact my oil drain intervals?
Specific oil drain recommendations vary widely depending on engine type, duty cycle, fuel type and other factors. As always, users should seek guidance from their engine or vehicle manufacturer regarding specific service recommendations.
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5. Do I need to adjust my used oil analysis program for API CJ-4 oils?
Yes, API CJ-4 oils may have a different fresh oil chemical profile from previous oils because one of the key requirements of the API CJ-4 category is the setting of maximum limits on the phosphorus, sulfur and sulfated ash content of oils. These limits are needed to protect the new 2007 advanced emission control technologies. Users should seek guidance from their oil supplier and/or engine or vehicle manufacturer regarding any changes to used oil analysis programs for API CJ-4 oils.
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6. Do API CJ-4 oils protect older engines as well as API CI-4 or API CI-4 PLUS oils?
Yes, API CJ-4 oils are designed for use in new engines as well as the existing on-highway fleets. API CJ-4 oils are qualified utilizing several new engine tests that are more severe than those used for API CI-4 or API CI-4 PLUS oils thus defining a new category of oils with much more robust performance than previous categories. API CJ-4 oils are formulated for improved wear protection, deposit and oil consumption control, soot-related viscosity control, prevention of viscosity loss from shearing, used oil low-temperature pumpability, and protection from thermal and oxidative breakdown when compared to previous API performance categories. As always, users should seek guidance from their engine or vehicle manufacturer regarding specific service recommendations.
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7. Do API CJ-4 oils protect older engines if they are operated on 500 ppm maximum sulfur fuel?
Yes, API CJ-4 oils are designed to have performance benefits over API CI-4 and API CI-4 PLUS oils when using both 15 ppm and 500 ppm sulfur fuel, and qualification testing is conducted using both fuels. As a reminder, 2007 on-highway engines with advanced emissions systems must use ultra-low sulfur diesel fuel containing 15-ppm sulfur or less. In cases where older engines/vehicles are operated with 500 ppm sulfur fuel, API CJ-4 is designed to protect the engine better than API CI-4 and API CI-4 PLUS. As always, users should seek guidance from their engine or vehicle manufacturer regarding specific service recommendations.
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8. Can API CJ-4 oils be used in off-highway applications?
API CJ-4 oils can be used in off-highway applications. However, the use of API CJ-4 oils with higher sulfur fuels, like those generally provided for off-highway use that may contain up to 5,000 ppm sulfur, may result in revised oil drain intervals and other maintenance recommendations. As non-road fuel sulfur levels are reduced, first to 500 ppm in June 2007 and then to 15 ppm in June 2010, manufacturer recommendations may be revised.
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9. When will API-licensed CJ-4 oils be available?
Oil marketers may license diesel engine oils meeting API CJ-4 requirements on October 15, 2006, and you can identify these oils by looking for API Service CJ-4 at the top of the API Donut or asking your bulk oil supplier. If you need API CJ-4 oils before October 15, 2006, contact your oil supplier. A complete list of API-licensed CJ-4 oils will be available at www.api.org/eolcs.
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