Fresh Oil

As the trucking industry prepares to bring into service diesels designed to meet the stricter federal emissions standards that take effect on October 1, 2002, the word from the engine-oil front is very upbeat. In fact, it's all good news for early adopters of the new cooled-EGR diesels that most engine makers will roll out by next fall expressly to meet those new limits, as well as for anyone who

As the trucking industry prepares to bring into service diesels designed to meet the stricter federal emissions standards that take effect on October 1, 2002, the word from the engine-oil front is very upbeat.

In fact, it's all good news for early adopters of the new cooled-EGR diesels that most engine makers will roll out by next fall expressly to meet those new limits, as well as for anyone who continues to operate “pre-'02” engines then and into the future.

First off, major oil suppliers are confident they will have oil formulations in the marketplace in ample time to properly protect those cooled-EGR diesels. That's important because those engines will be even tougher on oil than the current crop of EPA-compliant units.

What's more, the new oils formulated for '02 engines will boast “backward compatibility,” meaning they will also fully protect older engines, including those that currently use oil complying with the API (American Petroleum Institute) CH-4 service category.

But there's more. The new oils will meet the next API service category — most likely to be designated CJ-4, but possibly CI-4 — and will provide even higher-quality protection for older engines than products carrying the current CH-4 designation do.

To be technically accurate, these oils are still in development — as is the service category (again, most likely to be CJ-4) that will eventually adorn their packaging in the familiar API donut.

Call them for now what the oil formulators do — PC-9 (for the ninth proposed category) oils. Any oil today described as being “PC-9” is one that will comply with the lubrication performance requirements of cooled-EGR diesels.

While API does the actual licensing of the category, it's the ASTM (American Society of Testing & Materials) Heavy-Duty Engine Oil Classification Panel that sets the limits and verifies the testing used to develop each service category.

The panel's 15 members are drawn from major oil and additive suppliers and engine makers. The chairman is Jim McGeehan, manager of engine oil technology for Chevron Products Co., who has served on the panel all the way back to when category CE was developed.

According to McGeehan, this time around the big issue for oil formulators is combating the ill effects of adding cooled EGR systems to heavy-duty diesels, the approach all engine makers except Caterpillar are expected to use to further lower NOx (nitrogen oxides) emissions to meet the EPA's 2 grams/brake hp.-hr. limit for '02.

While cooled EGR cuts NOx, it increases acid and soot in the power cylinder and heat rejection to the coolant and oil. Those are the chief workaday issues PC-9 oils must address.

To develop PC-9, the ASTM panel has incorporated updated oil specs from Cummins and Mack that address the impact of EGR. The specs were written to ensure oil formulations will protect against ring, liner, bearing and valvetrain wear and to minimize viscosity increase due to soot and oil oxidation.


“The arrival of EGR makes for a much bigger challenge than we faced in developing previous oil categories,” McGeehan points out. “This will be the first time exhaust gas that's cooled will be put into the cylinders. This is quite a shift in engine design. But once PC-9 is fully defined, the result will be adequate engine protection for both existing and new EGR engines.”

The schedule for turning PC-9 into the next category looks like this: At a meeting on the 15th of this month, engine makers will propose limits for the PC-9 tests. The ASTM panel then discusses and finalizes them at a September 5th meeting. From there, a ballot vote is conducted, which should be concluded in October. After that, oil formulators can begin qualifying their oils for API licensing (probably as CJ-4), slated to begin next August.

Beyond PC-9/CJ-4, McGeehan points out that individual engine makers may elect to issue their own stricter specs to address extended-drain capabilities for their EGR engines. He says that will likely happen late this year, continuing the pattern first set after the previous diesel oil category (CH-4) was released.

“Any such action may cause additional changes to oil formulations,” McGeehan says, “or an oil company may choose not to meet those specs and stick with what's covered by PC-9.”

This isn't as counterproductive as it sounds. “The PC-9 category must be delivered in time for those EGR engines coming out,” says McGeehan. “But bear in mind the ASTM panel's work is a consensus-building process. Sometimes an engine manufacturer is not fully satisfied with all aspects, such as long-drain performance, and will issue its own spec later.

“The reality, too, is that manufacturers only have two or three new engines running in the field, so it may be hard for them to predict extended-drain capability as early as when the category is being developed.”

In the end, according to McGeehan, what the marketplace may get is two tiers of oil suitable for EGR engines. “What may occur is only the very top-quality formulators will meet all the specs for extended drain performance,” he advises.

Speaking specifically of Chevron's products, McGeehan says “we are very well-positioned to meet PC-9 and any additional OEM specs with our Delo 400. But we won't say we meet PC-9 until after the test limits are officially set.”

Another lubricant supplier confident about meeting PC-9 is Equilon Enterprises, the Houston-based company that manufactures and markets Shell and Texaco brand lubricants nationwide.

According to Greg Raley, commercial products manager for Equilon Lubricants Div., the company started its development of PC-9 oil two-and-a-half years ago.

And he says recent testing at the Shell Westhollow Technology Center indicates Shell Rotella T already meets or exceeds the anticipated requirements of PC-9.

Aimin Huang, Westhollow product development specialist and a member of the ASTM heavy-duty oil classification panel, says the oil will withstand the performance demands of EGR engines. “Although official pass/fail limits are not yet established,” she states, “we believe our testing data will satisfy the critical new engine tests within PC-9.”

As for what will make a PC-9 oil different, Huang explains that EGR introduces more soot into the engine and then into the crankcase. “The result,” she says, “is greater soot loading of the oil, greater tendency for corrosion from acidic properties, and higher oil temperatures.

“As a result,” Huang continues, “the oil must be formulated to improve soot dispersancy, to have better detergency to neutralize acidic properties, and have a more robust anti-oxidant package to improve stability and better withstand heat.”

According to Ralph Cherrillo, Westhollow technical advisor, along with ensuring engine durability and reliability, '02 oils should be formulated for “abuse tolerance” to protect the drain intervals many customers have become accustomed to.

“Mack has an EGR test,” Cherrillo relates, “that looks specifically at drain intervals with an eye to maintaining healthy bearings. For example, it will be necessary to make sure acidic leaching of lead from the bearings is kept to a minimum.”

Along with Shell's Rotella T, Raley reports that Texaco's Ursa Super Plus and Ursa Premium TDX oils will be capable of meeting PC-9 by the end of this year.


Both Huang and Cherrillo emphasize that PC-9 oils will also benefit older, pre-'02 engines thanks to their superior formulations. According to the two engineers, the greater dispersancy, detergency and antioxidant qualities of a PC-9 oil will “ensure older engines can use extended drains at a higher level of protection than they now enjoy.”

From the get-go, PC-9 was intended to produce a new API category that is “backward compatible,” meaning oils meeting it will provide protection for both existing and new cooled-EGR diesels coming to market by October '02.

“Backward compatibility is being taken very seriously by oil formulators,” says Michael Ragomo, ExxonMobil Corp.'s technical advisor for commercial vehicle lubricants. “The idea is not to develop oil that would be compromised if used in pre-'02 engines.”

Obviously, backward compatibility would benefit fleets, which would not have to stock and keep track of how two different API oils were used in different vintage diesels.

Ragomo says fleets may take one of two avenues to effectively protect a mix of EGR and earlier engines. “One approach would be to use only a PC-9 oil and define an appropriate drain interval for '02 engines. The fleet should expect their OEMs to provide some direction on setting that number. Then they could use that interval for both the old and new engines in the fleet.

“Or,” he continues, “the fleet could decide to use a PC-9 oil but run two different service intervals based on whether the engine is EGR-equipped or not. This approach would of course require more management effort but it would be a way to extract the most value from the lubricant used.”


Ragomo stresses a key aspect of any established drain interval is to observe it strictly. “A drain interval isn't fully effective if it's not done when scheduled,” he states. “You can't play averages with drain intervals. That is, a truck shouldn't have its oil changed early sometimes and late other times. Sticking to the schedule will be especially important for fleets running both EGR and non-EGR engines.”

Ragomo expects some engine makers will release their own oil specs even before PC-9 is officially released because they will have EGR engines “on the street” before next October.

“That's why oil formulators can't wait for the industry to issue a standard,” he states. “In our case, we choose to keep upgrading our higher-tier products. Mobil and Exxon engine oils, including Mobil Delvac 1, Delvac 1300 Super, Exxon XD-3 Elite and XD-3 Extra, will meet all PC-9 requirements.”

Mark Betner, Citgo's heavy-duty motor oil manager, says that once the ‘02 engines arrive, it will be more crucial than ever for fleets to work with their suppliers to determine the most appropriate drain intervals for various equipment.

“Even now,” he says, “when fleets ask us to advise which drain to run, there are eight or nine variables, including oil analysis, that should be addressed to get the right answer.

“It's really a matter of determining a ‘statement of capability’ in each case,” Betner continues. “One fleet may experience high idle times; another may run heavier loads.”

Rather than look for a mileage “bogey” to determine if an interval is safe or not — regardless of EGR — he says every fleet “would be wise to evaluate the drain capability of their equipment fully with the assistance of their lube supplier.”

Betner reports Citgo is “on schedule” for having its oil formulations ready in plenty of time for the arrival of EGR-equipped engines.

Ross Iwamoto, product development scientist for Tosco Corp., which markets 76 and Kendall brand lubricants, says PC-9 oils will essentially be evolutionary products, based on last-generation chemistry.

“We understand from our additive suppliers that only minor tweaking will be needed over what was done to achieve premium-level CH-4 oil,” he advises.

“The benefits from PC-9 oils will include improved dispersancy and oxidation control,” Iwamoto continues, “which means it will still be possible to run extended drains with older, pre-'02 engines.

“But,” he cautions, “engine makers have not yet set extended drains for their '02 engines and everything points to those being shortened — and significantly.”

As Iwamoto sees it, engine manufacturers will still want to keep their long-drain customers happy in '02 and beyond. “After CH-4 was released,” he notes, “both Cummins and Mack came out with higher-performing oil specs aimed at extended-drain users. That could happen again.”

As for meeting the '02 timetable, Iwamoto fully expects the industry leaders, including 76 and Kendall, to have their PC-9 formulations on the shelf shortly after the official limits are released.

When all is said and done, Iwamoto predicts the industry will be presented with oil that is of much higher quality — “I'd say 10-20% better” — than what's available for today's engines.

“These are exciting times for engineers,” Chevron's McGeehan sums up. “The EPA,” he adds on a light note, “certainly keeps us all well employed.”

Changing the oil…

Information on PC-9 formulations is available from these and other lube suppliers:

BP Lubricants 321
Warrenville, IL

Castrol 322
Baltimore, MD

Chevron 323
San Francisco, CA

Citgo 324
Tulsa, OK

Conoco 325
Houston, TX

D-A Lubricant 326
Indianapolis, IN

Exxon (Exxon Mobil) 327
Fairfax, VA

Kendall 328
Philadelphia, PA

Mobil (ExxonMobil) 329
Fairfax, VA

Pennzoil-Quaker State 330
Houston, TX

Phillips 66 331
Bartlesville, OK

76 Lubricants 332
Santa Ana, CA

Shell (Equilon) 333
Houston, TX

Philadelphia, PA

Texaco (Equilon) 335
Houston, TX

Valvoline 336
Lexington, KY

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