September 5, 2002 is donut day for engine lube manufacturers.On this date, the ASTM (American Society of Testing & Materials) panel will finalize the limits for the new engine oil category CI-4, which...
September 5, 2002 is donut day for engine lube manufacturers.On this date, the ASTM (American Society of Testing & Materials) panel will finalize the limits for the new engine oil category CI-4, which started off as PC-9(PC stands for Proposed Category).
As of September 5, engine lube manufacturers can be licensed to use the API (American Petroleum Institute) “donut”, CI-4 on their lubricant products targeting heavy-duty diesel engines. The API CI-4 standard replaces the old API CH-4 specification introduced in 1998.
Lube manufacturers have already started rolling out new high-performance engine oil formulations. Though expected to be backward compatible for pre-EGR engines, these new formulations will probably mean some changes for fleet managers with regard to price and drain intervals. We’ll take a close look at the new lubes hitting the market and outline the changes you can expect to deal with.
But first, some history.
As a result of a U.S. court settlement, engine OEMs and the Environmental Protection Agency (EPA) agreed to move up the 2004 emissions requirements to 2002. As a result, lube manufacturers have had to respond quickly with oils that could meet the punishing requirements of the new “cooled” EGR engines, which reduce levels of nitrous oxides but also run at significantly higher temperatures.
“The heat is coming from the EGR cooler, you’ve got exhaust gas going back into the intake stream. To get any appreciable amount of exhaust gas back into the intake, it needs to be condensed because the gases are so hot they’re very expanded. You need to run them through an intercooler, which is cooled by the same on-board coolant that is in the engine. The coolant temperature goes up, the engine temperature goes up, and the oil temperature goes up,” says Michael A. Ragomo, Products Advisor, Commercial Vehicle Lubricants, ExxonMobil.
These engines are also expected to produce greater amounts of soot in the oil. And this will have some severe effects on engine wear.
“We believe this is the biggest change in severity for an operating environment over any time before,” says Ragomo.
From the beginning, the CI-4 category was meant to have backward compatibility, so the oils being developed will provide protection for both existing and new cooled-EGR diesels coming to market by October ’02.
Following is a rundown of the new formulations the major motor oil manufacturers are placing on the market.
Petro-Canada will market its reformulated DURON heavy-duty engine oil against the CI-4 performance standards. “We’ve had the brand DURON since about 1999, and we’ve formulated it for CI-4, and we will have the API donut in all of our DURON 1540, DURON 1540 synthetic blend, and DURON 15W-40 full synthetic. The full synthetic and the synthetic blend will also include the Mack EO-N +. We are pretty confident that if we apply for Mack EO-N + that we’ll get it,” says Jim Abram, Petro-Canada’s Category Manager, Heavy-Duty Engine Oils.
DURON was originally formulated as a soot fighter, and Abram says dispersant chemistry and base oil quality will help when it comes to resisting viscosity thickened due to soot.
“Base oil quality matters even more. Currently, heavy-duty engine oils in engines with retarded timing absorb 1-3 percent soot; heavy-duty oils in EGR test engines have ended tests around nine percent soot,” Abram adds. Heavy-duty oils such as DURON are made from base oils of higher quality, such as API Group 2,3, hydrocracked and HT synthetic base oils. These thicken less as soot content rises, compared to Group 1 solvent refined heavy-duty engine oils. “Higher base oil quality translates into a retention of fresh oil properties longer,” Abram explains.
ChevronTexaco’s Global Lubricants’ Chevron Delo 400 Multigrade formulation has been available since 1998, and according to the company, this product did not need reformulation to meet the latest round of specification upgrades.
“Overall the product has got to do a good job of preventing against soot abrasive wear, which comes from the oil’s ability to disperse soot effectively and adequately,” says Mike Dargento, Senior Marketing Manager, Commercial Automotive Market Segments, ChevronTexaco. In December, 1998, when CH-4 took effect, the company’s Delo 400, which was in the marketplace since September 1996, was positioned to meet API CH-4. At the time, Chevron introduced a new Delo 400, positioning that for 2002 and EGR engines.
“Once we had a good idea of the test parameters and criteria for CI-4, we took the same formulation, tested it, and found that in fact we were correct with our product development process,” Dargento explains. “The Delo 400 product released end of ’98 did meet the requirements proposed for API CI-4 (PC-9 at the time).
Texaco’s Ursa Premium TDX and SuperPlus 15W-40 engine oils will continue to be marketed separately from the Chevron product following the merger. Company spokespeople say the product will be marketed for C1-4 application.
At Shell Canada, the company’s Rotella T is ready to go for CI-4 but the company is waiting for the Mack spec to be released before launching, says Crawford Smyth, Category Manager, Crankcase Lubes, Shell Canada.
“The EGR is going to give you more soot and we’re seeing more acidic type byproducts coming into the oil. So they are utilizing more and different detergents and dispersants to accommodate these new components; there’s more anti-oxidant additive going in because they are going to be operating at higher temperatures, and we know that’s going to be an issue. But they’re looking for two other parameters in the engine oil that are going to change the base oil, not the additives. One of them is called NOACK volatility, restricted now to 15 percent maximum for all engine lubes. With the previous CH-4 the 15W-40 could be as high as 18 percent and a 10W-30 could be as high as 20 percent so you’ll see they’ve reduced that down, restricting the amount of oil that can boil off in this test,” says Smyth.
As a result, he says, the volatility of the base oils used is of paramount importance.
“It’s not just hydrotreated base oils, because not all hydrotreated oils have low-volatility. It is in fact the way in which either a Group 1 or Group II goes through a refinery – they’re going to have to change that to reduce the volatility. The other parameter that’s come along is the high temperature, high shear requirement for 10W-30. It’s now 3.5 minimum, and previously 10W-30s could be as low as 2.9. This is no problem on the 15W-40, which has 3.7 so they can meet that requirement. It’s really targeted at lower-viscosity base oils to ensure there’s adequate film thickness for heavy-duty engine oils. That’s going to put some restriction around the kind of base oils that you can use for 10W-30. It’s a new challenge, put it that way,” says Smyth.
ExxonMobil plans to upgrade all of its multigrade products to API-CI-4, and is currently issuing formal marketing releases on two products for the category: Mobil Delvac 1300 15W-40, and Exxon XD-3 Extra 15W-40.
“We were looking at formulation technologies that were more robust in terms of oxidation stability. To give you a feel for just how much of an impact we think this is going to be, some configurations were showing 20-30F temperature-rise relative to non-EGR configurations,” says Ragomo.
He points out that for every 18F temperature rise, the oxidation rate effectively doubles.
“What we’ve done is identify a new technology, trimer technology, available in Mobil Delvac 1300 Super, 15W-40, and it’s a surface active chemistry which inhibits the hot surfaces from allowing the oil to oxidize, so not as many acids are formed, and it’s a lesser burden on alkalinity reserve, so we’ve got a significant advantage with regard to alkalinity reserve, without the negative effects of higher sulfated ash, which can lead to greater amounts of piston deposits,” he says.
To combat the higher amount of soot dispersancy, ExxonMobil will use Group II + base stock, which has good low temperature pr
operties, and very little boil-off at high temperatures, says Ragomo.
“Eighty to ninety percent of engine wear, most people believe, is occurring during engine startup. So if you have an oil that isn’t flowing as well, it’s going to be even more magnified during startup. We believe that keeping an oil’s viscosity stable over a long period of time, is going to never be as critical as it is in an EGR engine,” he says.
WHAT ABOUT PRICING?
The demands of EGR engines will undoubtedly see the use of more additives and better quality base oils.
For the most part, the consensus is that this will probably lead to a price increase for CI-4 oils.
“They’re probably going up. There is in fact more additive required in the product and the base oils are going to be more like what we call special base oils, so there is some modification there. Both of them are going to impact economics negatively, we just don’t know how much yet,” says Smyth.
But even though the new lubes may come at a higher cost, says Ragomo, fleets may be able to extract more value out of running with them.
“If I have a pre-EGR fleet, and I can buy a higher-performing oil, I might be able to extract a lot more value out of that lubricant. A price increase may result in more value in the lubricant when you factor in the potential to extend drain intervals for the pre-EGR engine,” he says.
IMPACT ON DRAIN INTERVALS
The exact extended-drain capabilities, at this point, are also difficult to predict, however. The goal, though, is to maintain current drain intervals between 30,000 and 40,000 miles, depending on the manufacturer. But shortened drain intervals wouldn’t be unlikely.
“There will be a specific drain interval tied to the Cummins and Mack specs. We believe they’ll be in the area of 30-40,000 miles, but we don’t know that for sure because the specs are still under development,” says Dargento.
“We feel we’ll meet those specs too without reformulation. It’s probably going to be more like 30,000, but it’s too soon to tell at this point. There are few EGR engines in field service today, and engine manufacturers are working hard to meet the September deadline or try to have their engines in the marketplace prior to then,” he says.
“Can I say that there are going to be no cases where someone is going to have to back down drain intervals? That would be difficult because we haven’t seen any of the finalized engine designs yet,” says Ragomo.
So if fleets are running both pre-EGR and EGR engines, how can they best proceed with drain intervals?
“There’s a couple of approaches a fleet could take. One approach could be that they opt for the most common denominator, the most severe operation in the fleet, and run the fleet all on that same interval. Another option could be, they actually identify, for each segment of their fleet, whether it’s by model year or make or by emissions regulations, and run different drain intervals across their fleet,” says Ragomo.
Ragomo says ExxonMobil is in a position to support either one, but warns about false economics associated with extending drains.
“We believe anybody can extend drains, but are they going to compromise engine life?” he says.
THE NEXT ROUND
“From an industry standpoint, CI-4 is essentially done and work on PC-10 has begun. That will involve exhaust aftertreatment devices, in other words catalysts, to meet the 2007 EPA requirements. This will require heavy duty engine oils with much lower restrictions on sulfur and phosphorus and much lower sulfur-content diesel fuels to keep from ruining the catalysts,” says Petro-Canada’s Abram.
“I would say by the end of this year we should have some good data that better defines the direction of the industry. But based on what we know today, oils will have to change from a formulation standpoint. Exhaust aftertreatment system options for the future are currently under evaluation. The goal is to always allow backward compatibility,” says Dargento.
On the fuel side, that same technology will also require ultra-low sulfur diesel, so there are challenges not just on the lube but on the fuels as well.
Before turning their efforts fully to the next round of emissions requirements, though, lube and engine manufacturers have a huge task ahead dealing with what is already known about EGR technology, and what will result when the technology is in full operation.
When the 2002 targets came down 15 months earlier (than initially expected), this resulted in a reduction in development time for engines and oils. “Typically, an engine builder likes to build a new engine and go through rigorous evaluations, so I don’t think they’ve had the time to go through the same rigorous evaluation that they normally would like to do, and I think that’s going to impact, potentially, engine life, unfortunately, in the longer term,” says Ragomo.
WHAT THE OEMs HAVE TO SAY
Some OEMs plan to release their EGR engines before the EPA deadline, and additionally, their own oil specs even before CI-4 is officially released. Only Caterpillar, however, will not use EGR. They will use a technology called ACERT (Advanced Combustion Emission Reduction Technology), which includes the use of a hydraulically actuated electronically controlled unit injector (HEUI for short) system. The system will have exhaust aftertreatment devices, but will not be available until fourth quarter 2003.
There are 15 tests in total, but there are two that use EGR engines specifically. The engine tests, the Cummins M11 EGR, and Mack T10 EGR tests are the two that incorporate engines that have EGR engine aftertreatment systems. These engines run on test stands in laboratories, they are calibrated with parts measured, and they are recognized and registered within the industry as defined by the ASTM. “These are the two tests that really differentiate the CH-4 oils from CI-4 oils because the prior spec did not have any tests using EGR equipped engines. Both cost about $100,000 dollars per run. So the expense of testing your products as well as benchmarking competitive products is significant. It can be a very expensive process,” says ChevronTexaco’s Dargento.
Cummins has come out with their next spec for engine oils, CES 20078. Cummins issues “Conformance” letters which state that a product conforms to the CES 20078 standard. The first conformance letters were issued starting February 1, 2002. It’s essentially all the requirements of the proposed API- CI-4 but they added two other engine tests around wear. One is a Mitsubishi test and the other a Sequence III F out of the gasoline category. What they’re doing is giving the opportunity to launch CI-4 oils earlier.
Smyth says that the reason some OEMs wanted to launch some of their EGR engines sooner, is that part of the court settlement allowed them some credit if they got engines on the market early.
“Mack Trucks are in the same boat. They’re in the process of issuing their next category and there’s actually two of them. Right now they’re at Mack EO-M +, next will be EO-N, and EO-N Premium Plus.. The EO-N sounds much like API CI-4’s but we don’t know for sure yet. But EO-N Premium Plus will be even more stringent than even CI-4. We’re still waiting to see how stringent that’s going to be,” says Smyth.
Though Smyth says the Cat 1Q with EGR test has been pulled, because of too much variability in the matrix testing, the API has maintained the the Cat 1R and Cat 1N. Both tests measure deposits and oil consumption, but the Cat 1R has iron pistons and the Cat 1N aluminum pistons.