Tier 3 Engines: Their Impact on Oil Companies, Operators, and Maintenance Schedules
It all began with new standards called for in the Environmental Protection Agency’s 1973 Clean Air Act, amended in 1977 and again in 1990.
The goal was to set and achieve National Ambient Air Quality Standards in every state by 1975. Failure to reach that ambitious aspiration led to the 1977 revision. The 1990 Amendment focused predominantly on issues that had not been previously addressed or were insufficiently addressed: acid rain, ground-level ozone, stratospheric ozone depletion, and air toxics. It also recognized that changes in fuels and vehicle technology must play a part in reducing pollution.
As part of the plan to improve air quality, vehicle emissions and fuel standards were implemented to reduce emissions of lead, oxides of nitrogen (NOx), non-methane hydrocarbons, carbon monoxide, and other pollutants. The Highway Diesel and Nonroad Diesel Rules, finalized in 2004, mandated the use of lower sulfur fuels in diesel engines by 2007 for off-road diesel fuel.
According to the EPA, diesel engines contribute 12% of all NOx emissions. Off-road diesel engines are responsible for 44% of diesel particulate emissions and also emit volatile organic compounds and carbon monoxide (CO). To combat the problem, a complicated and frequently revised four-step program, the first federal standards for off-road diesel engines over 37 kilowatts (50 horsepower), emulates the regulations for highway heavy-duty engines on a staggered schedule.
Tier 1 was phased in from 1996 to 2000, reducing allowable NOx emissions by 30%. Increasingly more stringent standards were scheduled for phase-in over time: Tier 2 from 2001 to 2006, and Tier 3 from 2006 to 2008, reducing NOx by another 70% and particulate matter (PM) by 40% from uncontrolled emission levels. The final wallop (Tier 4) is on the 2010 horizon. It requires a further 90% reduction in NOx and PM emissions beyond Tier 3 requirements, as well as a reduction of allowable sulfur in nonroad diesel fuel from 5,000 parts per million to 500 parts per million in 2007, and to 15 parts per million in 2010. The low sulfur levels are deemed necessary to achieve the Tier 4 NOx standards because sulfur fouls catalytic systems that are needed for low-NOx emissions.
By reducing PM2.5 and ozone through implementation of this rule, the EPA expects to prevent 9,600 premature deaths, 8,300 hospitalizations, and almost a million lost workdays. A secondary benefit includes the ecological impact.
The Cost of Development
Of more immediate concern to many original equipment manufacturers, oil and lubricant producers, contractors, equipment managers, and operators is the impact this sliding scale of regulatory reduction will have on their business, their budget, and their operating procedures. “Changes have taken place as everyone is ‘forced’ to meet the emissions requirements—and there are more changes on the way,” postulates Greg Shank, manager of engineering and product development and coordinator of lubricants and fuels for Volvo Powertrain, North America. Unfortunately, he adds, “Everything affects engine oil negatively, so we have to improve the quality of engine oil.”
To do that, he says Volvo engineers try to predict what performance improvements will be needed. He says “predict” because typical development begins two years in advance, before Volvo sees a new engine design. Once a formulation has been determined, Shank explains that engine tests are designed to measure oil performance improvements. Initial testing is done in a laboratory setting in order to ensure that the only variable is the oil. “It’s an exact process. We measure it in the engine, check for wear on the piston rings and cylinder sleeve, look for deposits on the pistons. … Oil formulations can be driven by particulates.” Working together with the OEMs to factor the improvement of the oil through the lab stage, Volvo then takes the product to the field for more tests. “It’s an additional spec Volvo requires.”
Dan Arcy, technical marketing manager with Shell Lubricants, elaborates on Shell’s development process, explaining that the Engine Manufacturer’s Association makes a request to the API/EMA Diesel Engine Oil Advisory Panel for a new oil to be developed for use in a new engine. The request includes the changes that have been made and the anticipated needs. Like Volvo, Shell then develops a test program to ensure its new oil meets the requirements. Then, “we get a prototype engine and run a prototype oil. It takes time.” And, he adds, money. “There’s a lot of cost involved. Developing categories has gone up significantly.” In addition, he says years ago a category may have required only a few engine tests; however, now there are numerous engine tests that must be run. The Caterpillar C-13 test, which is required for CJ-4, is a 500-hour test at a cost of around $140,000. Other tests, such as the Mack T-11 and T-12, are about $60,000 and $100,000, respectively. “You may have to run it several times to get the performance you are looking for.” Again like Volvo, Shell conducts field tests in addition to lab tests. “We run several million miles in the field to avoid issues. It takes time, and with regulations coming faster and faster, it’s expensive.”
Brent Birch, lab manager for product research and development and quality testing with Champion Laboratories Inc., maker of Luber-finer brand filters, recalls that in 1971 it took about three engine tests to win approval for a new oil, at a cost of about $1.5 million. By 2002, 16 tests were required, at a comparably escalated cost of $16 million. For 2007 and beyond, he predicts it will take 24 to 25 tests. He declines to put a dollar figure on the process, concluding merely, “It’s a huge investment.”
A huge investment has already been made to meet Tier 3 requirements currently in effect. As Arcy explains it, changed settings, timing, and engine components put more strain on the oil, which had to evolve in order to protect the engine. “EPA-driven regulations changed engine design. Because of that, oil marketers have to upgrade their formulations. Oil has to handle higher temperatures and more soot.” In addition to changing to better protect the engine, oil had to comply with limited volatility to meet Tier 2 and 3 requirements. The evaporation rate at certain temperatures had to be adjusted because the older oils had too much evaporation.
He confirms that Shell’s American Petroleum Institute (API) CI-4 PLUS formulation meets all Tier 3 requirements but says for the last two years, the oil company has been preparing for the change due October 15, 2006, when a new spec is mandated. The American Petroleum Industry’s new category of oils, CJ-4, meets the strict EPA requirements as well as the needs of the new engines. “CJ-4 is a big technological leap from prior categories. It protects the durability of the Diesel Particulate Filter and the engine.”
The new performance requirement for API CJ-4 will require higher-quality Group 2 base oils to be used, explains Arcy. The higher-quality base oils are necessary to help handle the extreme levels of soot and higher temperatures generated by exhaust gas recirculation (EGR). “The newer oils should have better soot-handling ability, better oxidation stability, and deposit control. There will be a step up in performance that will benefit the older engines as well, with improved wear protection.”
Chevron Products Co.’s diesel engine oils, including Delo, Ursa, and RPM, have passed all API and OEM tests required to meet the new API CJ-4 diesel engine oil service category. Chevron’s new CJ-4 products, to be known as Delo 400 LE (Low Emissions) Multigrade SAE 15W-40, Texaco Ursa LA (Low Ash) SAE 15W-40, and Chevron RPM LA (Low Ash) SAE 15W-40, have completed and exceeded all the requirements for API CJ-4, CI-4 PLUS, CI-4, CH-4, CF, SM; Caterpillar ECF-3; DDC Power Guard 93K218; Cummins CES 20081; Mack EO-O Premium Plus 07; Volvo VDS-4; and MB228.3.
Additives and specialty chemical producer Lubrizol at Wickliffe, OH, supports the API-adopted first license date of October 15, 2006, noting that API CJ-4 offers superior performance over API CI-4 in the areas of emissions; bearing protection; valve train wear protection; lower oil consumption; control of piston deposits; and oil shear stability.
Lubrizol’s testing demonstrates that API CJ-4 is backward compatible but that all currently licensable categories (including API CF-4, CG-4, CH-4, CI-4, and CI-4 PLUS) are not forward compatible due to the chemical limits for ash, phosphorous, and sulfur defined by API CJ-4. Of special concern is the degradation of particulate filters with the use of API CI-4 in 2007 engines.
On June 16, 2006, ExxonMobil introduced Mobil Delvac 1300 Super to meet API’s CJ-4 and CI-4 PLUS specifications. In its announcement, Douglas Pond, commercial vehicle lubricants advisor–Americas, ExxonMobil Lubricants & Specialties, said, “With new US Environmental Protection Agency emission regulations for heavy-duty vehicles taking effect in 2007, diesel engine oil performance requirements will become more stringent.”
Also this past June, Petro-Canada announced the launch of an API CJ-4 certified heavy-duty engine oil—Duron-E, featuring enhanced soot fighting capabilities in addition to improved wear protection, oil consumption, and piston deposits versus oil meeting the previous CI-4 Plus service category, the oil-maker said. Duron-E is available in three offerings: Duron-E 15W-40, Duron-E XL synthetic 15W-40, and Duron-E Synthetic 10W-40.
Making the Grade
To meet the new emissions targets, engine manufacturers propose the use of exhaust emission control devices and systems to filter out solid material. EGR, clean gas induction, and diesel particulate filters (DPFs) can help lower NOx in emissions, Arcy explains. “They pull little air from the exhaust as part of the intake air-charge to help reduce combustion temperature.” Since NOx emissions form at high temperatures, the theory holds that they should be reduced as a result of the lowered temperature.
The addition of the various after-treatment systems will add to the cost of new vehicles, will require the use of CJ-4 oils, and could potentially cause an increase in fuel consumption. Due to the engine changes and the new EPA diesel fuel regulations mandating an ultra-low sulfur diesel fuel in order to reduce NOx and PM emissions, Arcy acknowledges that correlating changes had to occur in oil formulations. “They [OEMs] are going to displace air with inert gas to lower temperatures and NOx emissions. It’s not a new concept; it’s been on cars since about 1978. But it affects oil manufacturers—what deposits can get into the engine.”
Because use of EGR will spawn higher operating temperatures and soot levels, CJ-4 oils have upped the ante in the battle, with better wear and deposit control and oxidation stability. Arcy recounts some of the challenges of creating a compatible and effective formulation: “We started testing in 2004, but this has been our busiest year with all the changes in emissions, fuel, and oil. Ceramic diesel particulate filters will remove black soot and ash particles from the exhaust. That’s a change for us. We put detergents in our lubricants: anti-wear agents in the oil. But this limits the types of detergents we can put in the oil. The CJ-4 limits of sulfur at 0.4% and phosphorous at 0.12% will have an effect on after-treatment devices. We had to replace the phosphorous to maintain wear protection. The performance is still there, but the negatives are that when we have to do more development work, it impacts the cost.”
Meeting the Challenge, One Tier at a Time
Because these staggered changes were decided on in 2002, Arcy says Shell has been able to plan ahead. There are no surprises. “We’re already doing research and testing for 2010; we know it’s coming.” Another advantage he believes Shell has is its ability to draw on global experience and learn from European technology development. “Other markets overseas are using select catalyst reduction instead of DPF. European regulations are on a different timing, but we’ll be going to that technology in 2010.” Along the way, he says they can learn from their counterpart’s history of application.
Oil manufacturers can’t afford to stand still: Research and development has been going nonstop. Although the off-road regulations have been lagging on-highway regulations by a couple years, Arcy notes that Tier 4 is bearing down on off-highway applications. In fact, Shank says, Volvo is no longer “paying attention to Tier 3 emission levels; we’re already there. We’re focusing on Tier 4. The 15-parts-per-million fuel spec is coming June 1, 2010. It’s a huge step; it means literally no sulfur.”
Further reducing NOx by 90% “will be a scramble,” forecasts Birch. Speculating that fuel injection system enhancements andcombustion management controls will advance, be very sophisticated, and become an integral part of the solution, he likens the situation to the catalytic converter issue in 1975 when lead had to be removed from gasoline to avoid poisoning the catalyst. “You must trap particulate matter in the diesel exhaust gas to meet PM requirements and, in most cases, use an oxidizing catalyst to control NOx.” Sulfur in diesel fuel must be largely removed to avoid poisoning the catalyst. The best choice with today’s technology is a particulate trap and/or an oxidizing catalyst. Many existing engines use EGR and recirculate soot. The benefit of a diesel particulate filter is that it reduces exhaust soot levels, and if EGR is extracted downstream of the trap, less soot is returned to the combustion chamber, taking some of the burden off the engine oil.
As one of the world’s largest filter manufacturers and suppliers, Champ Labs “piggy-backs with oil manufacturers” to create new products that comply with evolving regulations. “Data is still being developed that could change the current information this summer,” Birch says of ongoing R&D. “One of the big concerns as oil chemistry and vehicle conditions change is compatibility with materials such as sealing gaskets, media, and the adhesives used in assembly: metal end caps and resins that hold the media together. We’re looking at higher engine heat and chemical compatibility, which could cause gaskets to shrink or lose elasticity.” Naturally, Champ Labs conducts the standard industry tests, as well as field tests “for better compatibility and durability.” Under test conditions to date, Birch reveals, the new oil additives haven’t caused any issues with the filtration properties of their oil filter media.
Extending Drain Intervals—or Not
One issue on everyone’s mind during testing is drain intervals. Extending oil drain intervals is a goal for many equipment managers with off-road heavy-duty equipment. Benefits of longer intervals include lower disposal costs for waste oil and used filters, reduced costs for purchases of oil and filters, and less downtime for preventive maintenance and repairs, resulting in greater productivity on the job.
The question is whether extended drain intervals are feasible under the upcoming Tier 4 conditions. While Arcy says “some changes to reduce emissions generate minimal changes,” he anticipates Tier 4 changes could translate into higher fuel consumption in some engines. However, he adds, to offset the impact, operators should reduce idling time to reduce fuel consumption. Lowering idling time can also contribute to the possibility of lower maintenance costs and extended drain intervals.
Volvo already increased drain intervals to 500 hours with its Tier 3 spec, VDS-3. Shank predicts equipment managers won’t see another change in intervals until Tier 4 arrives. “Oil performance has improved. Drain intervals for VDS-2 and E-5, lesser spec oils that preceded VDS-3, were 250 hours,” he says. As the company works on its version of CJ-4, due in the market by the fourth quarter, Shank notes that they’ve made new improvements. However, it’s too early to determine drain intervals. “The fuel is changing. There’s sulfur in fuel, which creates sulfuric acid in the system that oil can’t fight off.”
More important than drain intervals, he contends, is engine protection. “We’re trying to introduce advanced emissions controls that don’t impact the durability of the engine. With EGR, if oil gets into improper condition, it affects the engine.” For that reason, he says most companies are nervous about increasing intervals at this point: There are too many unknowns involved in increased use of EGRs and low-sulfur fuel and oils under Tier 4. “Tier 4 is going to see all kinds of emissions equipment. Recycled exhaust is a negative for oil drains; EGRs require good oil. Our off-road people have been satisfied with 500-hour drain intervals; if we can maintain that,” Shank says, “we’ll be happy.”
Birch concurs: “We’ll be lucky to hold existing intervals when we change [to Tier 4] to PC10, the proposed oil category that will become CJ-4.” He describes CJ-4 as a ground-up product with a radically different composition. “It’s the first time limits have been applied to additives.” To meet emissions requirements and protect after-treatment devices on new and retrofitted equipment, there are now maximum limits allowed for sulfur, phosphorous, and sulfated ash levels. Sulfated ash is a buffering agent used to control acid buildup in the oil that results as a combustion byproduct from burning sulfur-laden fuels. Birch notes that a two-part solution, incorporating a diesel particulate filter and oxidation catalyst in the exhaust system, may be common. “When you reduce what’s in the oil—phosphorous, sulfur, detergents, and sulfated ash—new additives must be developed and utilized to restore some of the lost functions.” Sulfated ash acts as a buffer, keeping sulfuric and other acids under control.
“It’s a big project,” Birch confesses. New classifications of oil typically are better, offering a performance boost and less wear. While the new oil promises to deliver better wear and deposit control and higher oxidation stability, the familiar anti-wear components have been reduced. That is one reason the CJ-4 chemistry is unique.
Arcy agrees. “New oils generally offer benefits, such as protection against oxidation and wear.” He suggests that lowering ash could extend the time before the particulate filter needs to be serviced because it wouldn’t have to be cleaned as often. However, he cautions that oil change intervals depend on the circumstances, noting that off-road situations lend themselves to contamination. “You often drain the oil in off-road equipment because it’s contaminated,” he says.
Birch points out another aspect of the graduated introduction of new regulations: The new CJ-4 oil will not only be used in new engines, it will also be used in existing engines and could react differently in them. Backward compatibility is the goal, he explains; however, he’s not ready to say if drain intervals in older engines using CJ-4 can be extended or even held. And, as he reminds equipment managers, the old engines will still have residue from the old oil to contend with.
Arcy mentions tax credits for retrofitting equipment, along with other benefits: “Maintenance is reduced on retrofitted equipment.” Shank acknowledges that a lot of cities that want to look “clean and green,” such as New York City, are doing “ a lot of retrofitting” but says there’s not much of it going on in the off-road industry, although it is possible to rebuild engines to meet the requirements. “They’re concerned with the emissions effects it has. We give opinions, but we’re not in that business; we don’t do after-market.”
When the new engines come out in October, Birch says demand for CJ-4 will begin, but he anticipates a ramp-up to big sales volumes before CI-4, the oil currently on the market for Tier 3 applications, goes away. It’s an unusual situation. “Usually oil classifications just change and supersede each other relatively quickly. This is the first time there’s an overlap of this extent.” Oil companies won’t want to carry and market two inventories for the long haul, Birch believes, although it may take a couple years to phase out CI-4.
Meanwhile, because of the chemistry of CJ-4 (it has less reserve alkalinity), drain intervals in older engines remain an unknown. “We’re testing now,” he says, but adds that currently there’s not enough of a buffer to extend intervals. Champ Labs is running oil analyses to get a baseline with CI-4. In addition to those tests, Birch says they’re taking samples of CJ-4 at 75% intervals to help determine if intervals can be maintained.
“Off-road still uses 5,000-parts-per-million sulfur until later this year,” Birch elaborates. “We’ll be watching the acid content with CJ-4 in older engines. In a year, it may be no big deal. We’ll work for drain interval extension when we have more data. Ultimately itcould mean a revision of CJ-4. Oil is typically an evolution.”
The Economics of Emissions
Emission controls have also evolved—to the point, Shank says, where “there are times when the air going into an engine has a higher emissions level than the air going out because the standards are so high. It’s a good thing, but it’s not the perception most people have. It’s difficult to measure.” He says people are too familiar with the “significant pollution” from the diesel engines of the late 1970s–early 1980s. He cites “huge improvements” by the 1990s: “You rarely see a smoking diesel engine now.” While it may appear to some as an oil industry conspiracy for more profits, Shank dubs the regulations “environment-driven,” noting that “selling engine oil is not why Exxon made millions; it’s not on their radar screen of profit.”
The challenge is balancing the need to meet higher emissions standards with the cost of operation. While extended drain intervals offer a cost benefit, saving both time and money, Shank says the cost of the oil itself is relative. “The cost of lubricants and fuel to the end user is small. The cost of heavy-duty engine oil is really low comparatively. We’ve changed specs in three-year cycles, but prices haven’t changed much.” He points to higher production costs and small margins for additive manufacturers but says higher crude prices are only beginning to trickle down. For now, the bigger issue related to extending drain intervals centers around downtime. “If you can lower your downtime, you can be more profitable in the field and reduce your manpower requirements. If you’re doing fewer oil changes, you’ll need fewer mechanics.”
Nevertheless, he cautions that “it needs to be understood: There is a significant cost to the consumer” engendered by Tier 4 regulations—a cost shared by manufacturers. For one thing, the engines designed to cut emission levels have to burn more fuel to achieve that goal, meaning overall fuel costs will rise. The EPA “will always underestimate the costs, sometimes by a factor of three,” he warns. However, he acknowledges that the off-road industry typically uses its equipment longer, saving money and thus requiring an “incentive to buy new equipment. But, of course, that could all change under Tier 4.”
It could change sooner. Formerly, only southern California escaped the national aspect of exhaust standards, allowed to set its own, more restrictive standards because of its smog problem. These days, many regions hold jurisdiction to impose more severe restrictions than the national standard—and many contractors are finding early adherence to the coming Tier 4 regulations an advantage in bidding jobs. But installing after-market exhaust after-treatment devices to reduce emissions is expensive, with costs from $3,000 to $30,000.
“Diesel is an efficient way to create power; it has lasted because of that,” Shank continues. However, it’s poor quality in the US, he claims. “They took the sulfur out, but they could also remove other things—wastestream products.” As for emissions regulations, in looking ahead to the stringent regulations on the 2010 horizon, he can’t imagine a fifth tier. “I’m not sure we can do any better,” he says. From optimistic environmental beginnings to stringent restrictions, the industry has already come farther than it ever anticipated.
Writer Lori Lovely focuses on topics related to transportation and technology.