Since the 2007 diesel emissions regulations have arrived, engines work harder to control soot and particulate matter. This requires ultra-low sulfur diesel fuel (ULSD) for the new emissions control devices to function effectively. A reformulated diesel motor oil is also part of the solution. The new lubricant handles the higher temperatures in the new engines and minimizes diesel particulate filter (DPF) blockage.

Shell Lubricants recently completed the multi-city Shell Tech tour to update fleet customers on what to expect from the new motor oil, designated API CJ-4. Dan Arcy, Shell’s technical expert filled us in.

WT: When was the change?

DA: The official API (American Petroleum Institute) license date to change from the current standard, CI-4 PLUS, was Oct. 15, 2006. However, Shell has marketed CJ-4 oils in bulk and drums for customers with an early need.

WT: Is the new oil suitable for pre-2007 on-highway diesel engines?

DA:Yes, CJ-4 oil is compatible with pre-2007 engines. CJ-4 oils offer significant improvements in wear control, deposit control, and resistance to breakdown at high temperatures over the previous CI-4 PLUS oils.

WT: Can I top off CJ-4 with CI-4 PLUS?

DA: If you are using CJ-4 oil in pre-2007 engines, if necessary, you can top off with a CI-4 PLUS oil, though it is not recommended. However, in 2007-MY engines, CJ-4 oils must be used. Do not top off with a CI-4 PLUS oil.

WT: What happens if I put CI-4 PLUS oil in a 2007 diesel engine?

DA: If a CI-4 PLUS oil is used in a 2007 engine, the service interval for the DPF could be compromised as the higher ash-containing CI-4 PLUS oil results in more rapid blocking of the DPF. In addition, the older oil may not be able to withstand the more severe environment within the 2007 engines (higher temperatures, more exhaust gas recirculation), which may result in premature thickening of the oil, sludge formation, and resultant wear and corrosion.

WT: Can I buy CI-4 PLUS after the new diesel regulations took effect?

DA: Shell will produce CI-4 PLUS products until 2010 (when the next round of diesel regulations take effect) if there is sufficient demand from our customers.

WT: Does CJ-4 affect drain intervals?

DA: Based on hundreds of thousands of miles of on-highway testing of our next-generation oil, we do not anticipate that drain intervals will change for on-highway applications of current generation engines.

WT: How many flushes are needed when changing from CI-4 PLUS to CJ-4?

DA: It is not necessary to flush your engine when changing from the old oil to new.

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

DA:We don’t anticipate any change in oil consumption with the new CJ-4 oil.

WT: Can CJ-4 oils be used in off-highway equipment?

DA:Yes. Shell’s CJ-4 heavy-duty motor oils have been designed for use in off-highway equipment of all ages. Some had said that the higher fuel sulfur levels encountered in off-highway applications may require the continued use of CI-4 PLUS oils. This is not true — in 2007, the fuel sulfur levels for off-highway applications have been reduced to 500 ppm, the same as today’s on-highway standard. Shell has demonstrated the suitability of our CJ-4 oils in millions of miles of testing using conventional 500 ppm and under sulfur fuel.

WT: What does the new oil cost?

DA: API CJ-4 oils are estimated to be 10% to 15% higher versus 2006 prices, though Shell distributors and retailers are free to manage pricing for market conditions.