The Oil Never Rests

With CH-4 just put to bed, lube suppliers are taking on two more motor-oil categories - in very short orderLubricant engineers now know all too well what hot-dog attorney F. Lee Bailey meant about the defense.Before the Environmental Protection Agency (EPA) began mandating emission levels for diesels, the life span of heavy-duty oil service categories extended so long that rolling out a new API (American

With CH-4 just put to bed, lube suppliers are taking on two more motor-oil categories - in very short order

Lubricant engineers now know all too well what hot-dog attorney F. Lee Bailey meant about the defense.

Before the Environmental Protection Agency (EPA) began mandating emission levels for diesels, the life span of heavy-duty oil service categories extended so long that rolling out a new API (American Petroleum Institute) "donut" was practically an epochal event.

But now time really flies. Since the 1998 round of engine-emission regs, the lube industry has scarcely caught its breath - let alone gotten to rest - before delivering a new API category.

So it went last month. Along with rolling the licensing date for CH-4 oil from April of next year to December of this year, the API voted to proceed with the development of its next heavy-duty service category.

As Proposed Category 7.5 ("PC-7.5"), it follows on the heels of PC-7, which became API's CH-4 when finalized. Like its namesake predecessor, PC-7.5 will address the oil-related needs of diesel engines designed to meet the 1998 emission rules.

What's more, API is also gearing up for PC-9, the next proposed category for U.S. heavy-duty diesels. It is targeted for completion by January 2002. Hitting that date would allow products to be in place for lubing engines designed to meet the next round of emission regs, currently slated to take effect in 2004.

As it stands now, PC-9's main function will be to counter the ill effects of adding EGR (exhaust gas recirculation) technology to diesel engines to slash emissions further. The looming specter of EGR already casts a shadow over the future of the extended oil-drain intervals now embraced by some fleets and approved by certain manufacturers.

Getting back to the present, the specific differences between what's contained in CH-4 and PC-7.5 will reflect concerns voiced this year by engine makers. As it happens, heavy-duty diesel suppliers are now gnawing a bone of contention with the EPA over how new engines will be certified to comply with existing 1998 emission regs if the federal testing cycle is adjusted.

At presstime, most engine makers (a notable exception is Mack, which is being sued by the EPA and is counter-suing the agency) were negotiating individually and collectively with EPA over the issue of whether their '98 powerplants are using "devices" intentionally designed to bypass or defeat emission controls.

Since these talks are being conducted under gag orders, no one knows for sure what the outcome will be.

However, a key expectation is that EPA will issue a new certification test cycle that will more clearly reflect the emission of nitrogen oxide (NOx) when vehicles are operating under "normal highway" conditions.

Apparently, EPA's existing test cycle only accurately predicts the level of NOx produced by urban stop-and-go operations. (For more details on these developments, see "Dateline News," 7/98, pg. 16; or visit our Web site at

The upshot - and hence the genesis of PC-7.5 - is that engine makers will have to retard the timing of their engines to pass revised certification test cycles. Dialing back timing will put more soot into the crankcase, thus requiring motor oil to work harder than ever.

Although API ultimately approves proposed categories for licensing, the ASTM (American Society of Testing & Materials) committee on heavy-duty oil classification actually prepares the performance specs of each new category.

According to its chairman Jim McGeehan, Chevron's manager of engine oil technology, the committee is charged with completing the PC-7.5 category by this December.

If that schedule is met, oil and additive suppliers will have a year to get their products prepared in time to be licensed for the new category by API starting on January 1, 2000.

PC-7.5 will be designed to allow oils to be formulated that will handle the greater soot levels expected to be produced by revised '98-spec engines. "Retarding the fuel timing on these engines will reduce peak flame temperatures, which will lower NOx levels," points out Chevron's McGeehan.

"However, there are disadvantages to this approach," he continues. "You end up with more soot deposited in the oil, which can lead to more abrasion and sludge formation on filters if it's not dispersed."

The goal of PC-7.5, according to McGeehan, is to allow oil to be formulated that will maintain current engine durability and recommended oil-drain intervals. "The technology already exists to meet the parameters PC-7.5 will spell out," he notes. "The real technological challenge will be PC-9, since no heavy-duty diesels using the type of EGR design needed yet exist."

To bring PC-7.5 in under its short deadline, McGeehan says his ASTM panel will focus on tightening up some of the engine tests used for CH-4. "We will probably make limits on the Cummins M-11 and Mack T-9 tests (which evaluate wear performance) and the Mack T-8E test (which measures soot dispersancy) more severe," he advises.

With the ink not yet dry on CH-4's API donut, engineers at major oil companies are nonetheless resigned to tangling with a fresh oil category.

"It took three years to define the last proposed category," notes Bob Juett, senior staff research engineer for Shell Oil. "But the engine makers want PC-7.5 defined in only six months.

"If PC-7.5 isn't finished on time," he continues, "the engine companies have indicated they will require each oil to meet the tighter tests individually."

As Juett sees it, walking away from the trusty API/ASTM licensing system would result in "pandemonium," creating confusion in the fleet marketplace and driving up the cost of developing new oil formulations. He reports that Shell was "ahead of where we needed to be" when it introduced product formulated for CH-4 back in January.

"Each oil company has to wait for PC-7.5 to be finalized," Juett allows. "As it so happens, we already have other formulations we may draw on, but there's still substantial development costs incurred for any new oil."

Echoing that sentiment is Tim Devens, product line manager for heavy-duty oil at Exxon. "PC-7.5 will be controversial," he reckons, "given that a lot of companies haven't yet recovered what they spent on CH-4 formulations.

"Funding will also be an issue when we get to PC-9," he continues. "The current EPA action suggests retarding the timing as the next step. But as emission limits get tighter in the next decade, EGR and even catalytic aftertreatment may be needed. As time goes by, funding will be an issue. There's concern that PC-7.5 will dilute what monies are available to accomplish PC-9."

Or as Tom Olszewski, Exxon senior staff technical specialist, puts it, "The boulders are already out of the oil - now we start removing the pebbles."

While PC-7.5 oil is not expected to impact current oil-drain intervals, Olszewski cautions that may not be the case when PC-9 arrives. "Fleets that now extend drains without really thinking about it could run into trouble when emission regs get tighter.

"On the other hand," he continues, "we feel that even then field-testing could be conducted to set drain intervals safely. As a competitive measure, OEMs don't want to be the first to roll back their approved intervals.

"Certainly, there will continue to be pressure to help customers save money on drains," says Olszewski. "But to be effective, programs for extending drains must properly assess the risk for the engines involved."

He also advises that whether drains are driven by emission-related changes or even concerns about vehicle resale value, it's best to think in terms of "optimizing intervals, not just extending them."

Four-letter word Even without extending drain cycles, soot is now the biggest four-letter word confronting heavy-duty oil. Dan Arcy, product manager for commercial engine oils at Pennzoil, points out that several tests required to meet the CH-4 category are soot-related.

He says the Cummins M-11 test measures an oil's effect on soot-related valvetrain wear while the Mack T-8E test examines how well an oil resists thickening. The Mack T-9 test looks at how well oil protects against ring and liner wear and bearing corrosion. A 500-hour test, the T-9 is intended to help judge extended-drain performance.

"While engine companies can address EPA concerns by retarding timing," says Arcy, "there are penalties. Besides increasing the soot deposited in the crankcase, which oil formulations must address, engines could end up with reduced fuel economy and horsepower.

"When emission regs get still tighter, EGR will be a possible remedy," he continues. "PC-9 will have to deal with the effects that technology has on engine performance. It's possible that using EGR would boost soot deposits by 8-10%. If that happens, the industry will see shorter drain intervals."

According to Arcy, it's too early to say for certain how much EGR will impact extended drains. "We expect they'll get backed down somewhat," he advises. "Still, we don't know what relief new oil technology may provide."

"The changes EPA will bring to '98 diesels could generate up to 30% more soot for the oil to handle," says Dick Morrow, senior staff engineer for Mobil. "As a result, the engine makers don't think CH-4 oil will be good enough."

Like his counterparts at other oil companies, Morrow says it's too early in the game to predict how oils will be formulated to meet PC-7.5. However, he says Mobil feels it has "reserve capability" in its existing formulations to help it meet the new category's tighter specs.

"We've already formulated our oil for extended-drain capability," Morrow continues. "And that's what the PC-7.5 category is aimed at."

"EPA regs for air quality control will continue to be the main driver behind new oil formulations," remarks Steve Hutchinson, vp-marketing, for Dryden Oil Co.

"As emission specs get tighter," he continues, "expect to eventually see drain intervals reduced to maintain the wear protection of oils that will have to work much harder. The biggest impact will come by 2002, when the increased soot loading of EGR engines will have to be addressed."

Drain watch According to Bill Gaw, research associate at Conoco, if the changes in oil formulation promised by PC-7.5 are not made, there could be "substantial reductions" in drain intervals.

"As for PC-9," says Gaw, "both soot loading and EGR are very hard on oil. No one knows how severely the next generation of emission-controlled engines will affect oil performance. But it's safe to say drain intervals will have to be set to reasonable limits for those engines and the oil they use."

"Until EGR arrives," agrees Bill Putman, Conoco's sales development manager, "we'll still see the same levels of performance from oils." However, he cautions that even though CH-4 and PC-7.5 formulations will be up to par, fleets should be aware of another effect current engines can have on oil performance.

"The '98 engines definitely put a greater workload on oil," says Putman. "At the same time, these new diesels require less makeup oil. That means the additives in the oil are not being replenished in service as quickly as in the past. So, at the same time more burden is being placed on the oil, less new oil is being added between drain intervals."

In general, oil companies agree on two central tenets. Firstly, drains should not be extended haphazardly. Instead they recommend advancing intervals in stages - and using oil analysis as a progressive safeguard. Secondly, pulling extended drains on schedule should not be taken lightly.

Dick Patrick, product specialist at Citgo Petroleum Corp., is concerned that the rapid arrival of new oil categories "confuses the issue of extended drains" for fleet operators.

"A lot still has to happen, especially before PC-9 picks up," says Patrick. "Not only are there no EGR engines yet available for testing lubes, but members of the Engine Manufacturers Assn. must stay mum outside their own group or risk legal action by the EPA. That, of course, hampers the communications needed to develop new oil formulations."

Patrick says it's hard to know how long these "windows of forced confusion" will remain open. "There's also the related question of how much leeway will be allowed for development, considering the much shorter timetables set for producing the next two oil categories.

"The proper perspective may be to remain in something of a holding pattern," he adds, "at least until the hardware issue of EGR is settled. Before we can do anything about PC-9 oil, we'll all have to get our feet wet with those engines first."

To be sure, the people who put together the motor oils fleet managers depend on will never rest. Not so long as regulations - and customer needs- demand that lubricant technology be driven ever forward.

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