Understanding API CJ-4

Frequently Asked Questions

Can I top-off API CJ-4 oils with API CI-4 PLUS products.

Yes and No. Typically, topping-off a API CJ-4 product with a API CI-4 PLUS oil is not recommended. There are some exceptions, depending on the model year of the engine. To further explain, if you are using API CJ-4 oil in pre-2007 engines, if necessary, you can top-off with a API CI-4 PLUS oil. API CI-4 PLUS oil meets all the requirements for pre-2007 engines. In 2007 model year engines, API CJ-4 oils must be used and you cannot top-off with a API CI-4 PLUS oil. However, if the choice is low oil level or using API CI-4 PLUS oil, add the API CI-4 PLUS oil, but change the oil as soon as possible.

Are API CI-4 PLUS and API CJ-4 oils compatible?

Yes. API CI-4 PLUS and API CJ-4 oils are compatible, (i.e., they can be mixed without fear of adverse chemical reactions causing deposits or additive fall out). However, mixing in API CI-4 PLUS oils, (e.g., for top-off) can result in reduction of performance of the oil as API CJ-4 oils offer higher levels of protection than API CI-4 PLUS oils.

Can I mix the two oils?

API CJ-4 and API CI-4 PLUS oils are compatible with each other. However, we don't recommend actively mixing the two products, as there are differences that will be evident in the used oil analysis and potential reduction in levels of protection compared to API CJ-4 oils.

Will the customer see any differences when they change to API CJ-4 oils?

If you are conducting used oil analysis, you will see a difference in the concentration of the additive metals.

Will it look any different or smell any different.

There will not be any noticeable difference in the physical appearance or smell of the new API CJ-4 oils.

What will the differences be and the advantage be in switching to the new API CJ-4 oil?

In 2007 model year engines, API CJ-4 oil will be required to protect the engine and allow for maximum durability of the exhaust after-treatment system.

In pre-2007 engines, API CJ-4 oil will provide the latest in protection, including improved wear protection, high temperature oxidation control and soot handling which will enhance engine durability and cleanliness of the engine.
Will my warranty be affected if I don't use API CJ-4 oils?

These new oils were designed for use in 2007 U.S. on-highway emission controlled engines. Engine oil recommendations and warranty policies vary by manufacturer. Consult your operations and maintenance manuals for guidance for your specific hardware and application.

What happens if I put 2006 oil in a 2007 engine?

If a API CI-4 PLUS oil is used in a 2007 engine, the service interval for the diesel particulate filter (DPF) could be compromised as the higher ash-containing API CI-4 PLUS oil will result in more rapid blocking of the DPF. In addition, the CI-4PLUS oils may not be able to withstand the more severe environment within the 2007 engines (higher temperatures, more EGR) which may result in premature thickening of the oil, sludge formation and resultant wear and corrosion. API CJ-4 oils are designed to provide improvements in wear protection, high temperature oxidation control and soot handling required by the new engines.

How are engines changing in 2007?

Specific changes differ by individual engine manufacturers. However, in general, all 2007 heavy-duty diesel engines will incorporate exhaust after treatments devices which include a DPF, and some engines will also include an oxidation catalyst. 2007 diesel engines will require the use of ultra-low sulfur diesel (ULSD) fuel as well.

Depending on the engine manufacturer and vehicle design, some engines will run hotter than current engines.

Additionally, some engines will utilize higher levels of EGR (exhaust gas recirculation) or CGI (clean gas induction) to help meet exhaust emission requirements.

When switching my bulk tank from API CI-4 PLUS oil to API CJ-4 oil, how far down do I have to drain before it can be considered API CJ-4?

When switching from API CI-4 PLUS oil to API CJ-4 oil, we recommend you drain your tank completely. This will also give you the opportunity to clean your tank.

If draining your tank is not an option, we recommend commingling a maximum of 2%.

When changing my engine from API CI-4 PLUS oil to API CJ-4 oil, how many flushes do I need to do when changing over?

When changing your oil from API CI-4 PLUS to API CJ-4, it is not necessary to flush your engine.

Will I see any difference in oil consumption in my equipment?

We do not anticipate any difference in oil consumption.

Are there any special HSSE or used oil disposal procedures needed for the new oils?

The disposal of the new oil is the same as the older version. Check with your local authorities on the proper disposal of used engine oil in your area.

Can I use API CJ-4 motor oils for my off-highway equipment?

Yes. API CJ-4 heavy duty motor oils have been designed to be suitable for use in off-highway equipment of all ages. Some concern has been voiced that the higher fuel sulfur levels encountered in off-highway applications may require the continued use of API CI-4 PLUS oils. This is not true - in 2007 the fuel sulfur levels for off-highway are being reduced to 500ppm - the same as today's on-highway standard - and has demonstrated the performance and suitability of our API CJ-4 oils in millions of miles of testing using conventional <500ppm sulfur fuelOperators of off-highway equipment who also have on-highway trucks can benefit from the convenience of one oil for virtually all applications. Some marketers will be converting all of their diesel production and distribution to ULSD<15ppm sulfur, so the availability of >500ppm sulfur fuel for off-highway may be more limited as the industry protects the integrity of the road transport pool and prepares for the off-highway conversion in mid 2007. The use of API CJ-4 oils and/or lower sulfur diesel fuels present the opportunity to re-evaluate off-highway maintenance practices for optimized oil drain intervals.

How much more is the new oil going to cost?

It is true that API CJ-4 oils are much more costly to produce, in part, due to their higher performance in the areas of wear protection, oxidation control and soot handling capabilities. In addition, these oils also offer additional value in the form of increased durability of 2007 exhaust after-treament systems. It is estimated that the industry will spend millions of dollars on the development and oil qualification of the API CJ-4 category. This being said, it could be expected that versus today's prices, API CJ-4 oils could be 10-15% higher in cost.


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