A long time in the making

Fleet Equipment, Jul 2006 by Birkland, Carol

New 2007 engine oils are hitting the streets

No one can say the industry hasn't been preparing us for the introduction of the next generation of engine lubricants. We first heard of the proposed category (PC 10), which would be formulated to handle the demands of the 2007 on-highway engine emission regulations, more than four years ago.

A new category

The American Petroleum Institute, engine makers and lubricant suppliers spent several years developing CJ-4 for the 2007 emissions engines fuel with ultra-low sulfur diesel (ULSD) fuel. According to Reggie Dias, director of commercial lubricants for ConocoPhillips, the CJ-4 category tests included all those used for the previous API CI-4 lubricants plus three new engine tests.

"CJ-4 did well demonstrating that it fully meets pervious category engine protection standards with minimized complexity and meets the more sophisticated performance requirements of 2007 engines and their aftertreatment devices," Dias says.

The 2007 exhaust gas recirculation (EGR) engines with aftertreatment devices will operate at higher temperatures and have greater performance demands placed on them to remove NOx and particulates from the exhaust than previous engines, Dias says. One of the main challenges is to lower the levels of sulfated ash and sulfur in the lubricant for after-treatment device compatibility without sacrificing its engine performance.

"The CJ-4 lubricants have successfully lowered ash and the TBN and are still superior," says Dias. "This is due to the fact that the lubricant industry has come up with new technologies, a culmination of many things. First the elements of chemistry are balanced in a way that is significantly different than previous formulations. These include new additives to provide protection for the older engines and to meet the enhanced requirements of the 2007 lowemissions engines."

ConocoPhillips is one of the major oil companies that will have qualified product ready for introduction prior to the Oct. 15 deadline, says Dias.

"We've been working with major fleets testing our product in equipment operating on both ULSD and the higher sulfur diesel, and we have developed proof of performance on both our CJ-4 lubricants technology," he says.

ExxonMobil recently announced two significant changes to its premium line of Mobil Delvac heavy-duty engine oils. To meet the API CJ-4 diesel engine oil specification, which encompasses the new requirements for PC-10, the company will introduce a new formulation of Mobil Delvac 1300 Super 15W-40, in October. The new formulation will be backwards compatible and meet the requirements of CI-4 and CI-4 PLUS, and the company notes, it will help to extend the life of both new and older engines, as well as new emissions after-treatment systems. In addition to its reformulated Mobil Delvac 1300 Super, in October ExxonMobil will introduce Mobil Delvac MX 15W-40, which will exceed the API CI-4 Plus specification.

Alex Bolkhovsky, Commercial Vehicle Lubricants Technical Advisor, ExxonMobil Lubricants & Specialties for ExxonMobil, says, "We have done extensive testing, over 7 million miles of field testing, of CJ-4 on pre-'07 engines at standard oil drain intervals with good results. We have even been able to do extended drains for some customers, those with good PM and oil analysis programs. We see the drain intervals for CJ-4 on '07 engines remaining much the same as established by engine makers."

With use of the new DPF, a maintenance concern is going to be plugging, he says. Using the right oil and the right fuel will keep the filters from plugging, which can cause back pressure, lower horsepower, reduce fuel economy and degrade the lubricants more rapidly. Once a DPF starts to plug it will continue to plug at a faster rate.

"The need of sound practices will remain the same," says Bolkhovsky, "Drivers will need to be educated to take caution when fueling, technicians need to be made aware of the equipment they are working on and what fuels and lubes are being used. Right now people need to be informed of the changes."

CJ-4 roll out

There are three specific areas that were addressed to meet the government requirements for lower emissions for the 2007 engines, according to Dan Arcy, technical marketing manager for Shell Lubricants. Diesel fuel sulfur levels need to be at 15 ppm, the engines and aftertreatment devices need to be in place and the lubricants for those engines need to be able to perform on those engines and aftertreatment devices without having ill effects on either.

The industry is entering the roll out phase of the new API category CJ-4 lubricants. "In the next couple of months the new oil will be coming out," says Arcy. "The difference between this oil and previous blends is that CJ-4 is formulated to handle the higher operating temperatures of the new EGR engines and protect the aftertreatment devices. It will have better handling capability for the higher levels of soot without thickening and with better dispersants." The new lubricants will work within the mandated chemical limits of 0.12 percent phosphorous, 0.4 percent sulfur and 1.0 percent sulfated ash."