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New Motor Oil Category Makes Debut This Fall

Motor oil isn’t usually a topic that school bus fleet operators spend much time discussing. But that might change soon, after new-and-improved l...

by ry and photos by Paul Hartley
March 1, 2002
7 min to read


Motor oil isn’t usually a topic that school bus fleet operators spend much time discussing. But that might change soon, after new-and-improved lubricants start flooding the market. The new lubes, already available from some producers, are designed to handle the extra soot, acid and heat that’s expected to build up inside heavy diesels using cooled exhaust gas recirculation (EGR). EGR, of course, is the method of choice among most engine makers for meeting governmentally mandated emissions-reduction targets taking effect in October. Few school bus owners will have EGR systems in their fleets anytime soon, but all are going to benefit from the equipment’s requisite oil, which is technically known as API CI-4, its service category designation. New category is born
CI-4 is the latest in a series of categories that date back to 1947, when the American Petroleum Institute and several other groups started setting engine-oil standards. Before that time, oil was rated on its viscosity alone. In the current alphanumeric jargon, “C” means compression ignition, and 4 stands for four-stroke. The middle letter, “I” in this case, changes with each new level of performance. At present, Cummins is the only manufacturer with a diesel EGR engine ready for the North American school bus market. International recently joined the EGR club with its VT 365, but that product isn’t scheduled for bus applications until 2004. The temporary absence of EGR hardware, however, won’t slow the flow of CI-4 quality oils to school bus fleets. In fact, the new lubricant will likely replace the current variety, CH-4, in the coming months. “I don’t expect anyone in the U.S. or Canada to offer CH-4 oil after September, when CI-4 licensing begins,” says Matthew Ansari, heavy-duty automotive manager for ChevronTexaco Global Lubricants. “Usually, the older technology remains behind in the developing world.” Ansari says it wouldn’t make economical sense for large refiners to produce and distribute dual categories of oil when the superior blend basically replaces its predecessor and is fully compatible with any diesel or gasoline engine on the street. For the same reasons, he can’t imagine customers wanting anything but the latest formulations, even if they’re unnecessary for non-EGR engines. Several benefits seen
CI-4 oil, intended for severe service, is built with greater wear protection, more thermal stability, improved oxidation control and increased soot handling capabilities. This combination of factors should offer bus owners longer drain intervals and, ultimately, lower operating costs, says Dan Larkin, technical advisor for ExxonMobil. Larkin is intimately familiar with the CI-4 category. Formerly with Detroit Diesel Corp., he was the chairman of the Engine Manufacturers Association group that drafted the initial set of oil performance requirements for EGR engines. Some fleet managers are already considering the new oil’s possible impact on their operations. Greg Rees, with Jefferson County Public Schools in Lakewood, Colo., says he contacted his oil distributor soon after hearing about CI-4 several months ago. Rees, in charge of maintenance for roughly 340 buses, is hoping the category change enables him to stretch his extended drain program to new limits. That would be quite a feat. About 300 of his buses have Spinner secondary filtration systems and are set up on 12,000-mile drain cycles. The others are fitted with Puradyn secondary filtration, and their oil is never changed - just the filters, at 18,000 miles. Rees uses an ExxonMobil mineral-based oil and practices regular, fleet-wide oil analysis. Taking is slowly
Jeff Rodgers, transportation supervisor at Los Alamos Public Schools in Los Alamos, N.M., is also looking into the possible benefits of CI-4, but he’s is taking a much more cautious approach. Maintaining a fleet of 38 buses, Rodgers schedules oil changes at 4,500 miles and uses ChevronTexaco products. “We’re in a very compact district,” he says. “All the routes are low-speed, stop-and-go. We believe ours is a heavy-duty application.” Rodgers says he will be monitoring the new oil’s performance in the coming months and might make adjustments as they’re warranted. “Fleet managers are always looking for ways of cutting costs without cutting corners,” he says. Still, he’s satisfied with his current system and doesn’t intend to disrupt things just to pack an extra 1,000 or 2,000 miles between oil changes. “We’ve designed our preventative maintenance charts around the manufactures’ recommendations and the New Mexico state inspection requirements,” he says. “Our program has been working well for us. We don’t overhaul engines, and we have a very good reputation - not only across the state, but in surrounding states, too. When we buy new buses, we actually sell our traded buses for the dealer right in our lot. People buy them sight unseen. Because our maintenance program is what it is, our engines last as long as we own them, about 12 to 14 years.” Not all CI-4s are alike
Not everyone is as careful as Rodgers when it comes to vehicle maintenance. Some fleet managers, aware of the added capabilities of CI-4 quality oil, will probably soon try to cut costs by switching to the cheapest brands on the market. That would be a mistake, says Ross Iwamoto, product development scientist for Phillips Petroleum. “Brands are formulated differently, so they have individual performance advantages,” he says. “API’s categories are sort of a minimum standard. There is a lot of room to build in better performance than that.” Plus, the API licensing system is voluntary, so some lower-end products might not even meet the category criteria. Michael Monarchi, product manager at Pennzoil-Quaker State, agrees, adding that customer flight is a big concern among larger producers each time new categories are introduced. The hard part, he says, is convincing consumers that tangible differences exist between oils: “We live in a world where people don’t want to pay extra for added performance if it’s not readily apparent.” He says education is critical to ensure that a brand’s distinct characteristics are valued in the market. The publicity surrounding the introduction of CI-4 oil will, no doubt, help companies get their collective message out. The category has received considerable attention in recent months, largely because of its association with the EPA’s mandated diesel emission cuts. Tougher challenge ahead
The next category, tentatively dubbed Proposed Category 10 (or PC-10), will probably get even more fanfare. Due out in 2006, PC-10 will set the standards for oil used in 2007-model diesel engines, which will burn ultra-low-sulfur fuel and employ exhaust aftertreatments and other possible emission-reducing hardware. Engineers say the challenges in reaching the next level of oil performance are daunting and could require a whole new batch of additive chemistry. “Everyone is thinking that PC-10 oils will be ‘outside of the box’ from current oils,” says Iwamoto at Phillips. “This could mean that they won’t be compatible with any engines other than the ones they were designed to lubricate.” Such a scenario would certainly cause trouble for fleet managers because they’d have to stock two types of oil and make sure that employees correctly dispensed each. Work on PC-10 has just begun, so it’s possible that compatibility issues could be resolved during the next four years. That will be among the goals scientists pursue. Getting to that point, however, will require considerable research and money. About $5.7 million was spent developing CI-4 - and that just covered the establishment of testing procedures. Unfortunately for oil companies, this massive effort is lost on the buying public. “Consumers don’t realize or appreciate how difficult and expensive it is to develop new oils,” says Larkin at ExxonMobil. “They just care about having the best oil delivered at the lowest price.” Most oil industry experts anticipate little or no change between the price of CI-4 quality oils and their CH-4 predecessors. If this holds true, customers will be getting what they apparently want most from their lubricants, at least for the next four years. Advances in oil formulation can provide long-term benefits, such as extended oil intervals, but only if coupled with proper filtration. “Extended drains need a combination of good oil and good filters,” says Ed Newman, marketing coordinator for Amsoil Inc. He also touts the benefits of synthetic oil, which he says doesn’t break down or oxidize as easily as mineral-based oil. “It also has better extreme high- and low-temperature performance characteristics,” Newman adds.

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