It’s show time at last for the producers of motor oils developed through the API Proposed Category 11 process. PC-11 was launched in 2011 to develop specs for a new oil-service category to succeed the American Petroleum Institute’s CJ-4 designation. Along the way, PC-11 was split into two categories to better address the needs of current engines, as well as newer ones developed to comply with federal greenhouse gas/fuel economy rules.
The result was the simultaneous development of two new API categories: CK-4 and FA-4. CK-4 retains the higher-viscosity grades already familiar for use in current to older engines. FA-4 leverages lower-viscosity grades needed to improve fuel economy in newer engines starting with model year 2017.
“CK-4 oils will replace the current CJ-4 oils, and they are completely back-serviceable for all applications that required the use of CJ-4 oils,” says Tony Negri, HDEO product manager for Phillips 66 and Kendall Lubricants. “Along with the performance characteristics of CJ-4 oils, CK-4 oils will have improved resistance to oxidation, better shear stability, and more aeration control” to better protect engines and aftertreatment systems.
By contrast, he says, FA-4 oils will have lower viscosity grades and are designed for use with the next generation of diesel engines. “They will help improve the fuel economy of those engines while still offering excellent protection.”
In addition, Brian Humphrey, OEM technical liaison for Petro-Canada Lubricants, explains that CK-4 and FA-4 oils both are designed to improve resistance to aeration and have increased shear stability, “which will provide enhanced performance and greater hardware protection over time. Taken together, these improvements may reduce vehicle downtime, which is a major source of financial drain for fleet operators.”
API will license products under the new categories beginning next month. December 1 is the earliest date when the designations CK-4 and FA-4 can appear in the familiar API Donut on oil packaging, although some oils meeting those specs are already available in the marketplace.
There are three key questions the double rollout poses to fleet operators:
- What may be gained by choosing an FA-4 oil (in applications approved by your engine maker) over a CK-4 product?
- What are or will be engine makers’ application recommendations for CK-4 and FA-4?
- What impact might the new API categories have on oil drain intervals?
FA-4: What’s in it for fleets
As to the first question, a recent Confidence Report issued by the North American Council for Freight Efficiency and Carbon War Room, indicates there’s a fuel-efficiency gain to be had by switching to lower-viscosity oil, and that moving all the way to FA-4 will increase that benefit.
The report finds that over-the-road fleets can realistically expect fuel savings in the range of 0.5% to 1.5% if they switch from 15W-40 to 5W/10W-30 oil, whether it carries the CJ-4 or newer CK-4 designation. And moving to a 5W/10W-30 FA-4 oil could add a further 0.4% to 0.7% of fuel savings. In other words, switching from a 15W-40 CJ-4 or CK-4 to a 5W/10W-30 FA-4 oil should boost fuel economy by 0.9 to 2.2%.
“This is based on test data from oil suppliers and what OEMs and fleets told us,” points out Yunsu Park, NACFE program manager. “And given the amount of information and data that was shared, we have very high confidence that fleets will benefit from this switch.”
However, he notes that at this point, there is much less data available on FA-4 performance. “Only oil suppliers were able to share any meaningful data,” Park explains. “Due to the lack of fleet data or pricing information at this time, our recommendation is that fleets should consider testing once the [FA-4] oil becomes available.”
Given the difficulty fleets have verifying fuel savings of this degree with their own testing, the report suggests those considering switching to low-viscosity oil, regardless of API category, use a “conservative” 0.5% benefit when calculating payback. “If an acceptable ROI is shown with this low level of fuel savings, fleets should be able to confidently make the switch.”
Engine maker recommendations
As to the second question, Negri of Phillips 66 and Kendall explains, “FA-4 oils have not been fully endorsed by the engine builders as backwards compatible, so they may not be able to be used with all existing diesel engines. The engine builders will continue to evaluate these oils and refine their positions on backwards compatibility as more is learned. Most fleets can expect to first use CK-4 oils and may eventually use FA-4 products as they purchase new assets in the years to come or as allowed by their OEMs.”
Len Badal, Chevron’s global Delo brand manager, says pinning down what the engine makers will decide regarding application recommendations for FA-4 oil is “like nailing a piece of Jell-O to the wall. Whatever is said today may change in several months.”
Each heavy-duty engine maker has or shortly will issue application approvals and service recommendations regarding the two new oil types. At this point, only some are addressing both CK-4 and FA-4.
Detroit is providing the broadest guidance so far on use of CK-4 and FA-4 oils. “Detroit will issue two new fluids specifications; 93K222 will cover CK-4 oils and 93K223 will cover FA-4 oils,” says Greg Braziunas, Daimler Trucks North America manager, oil and coolant systems, mechatronics and durability interface. “Detroit will be publishing extended oil drain intervals that will apply to 93K222 and 93K223 approved oils, with more details forthcoming.” He adds that 93K223-spec (FA-4) oils will be “allowed for use in all Detroit engines that are EPA10 and newer model years.”
Paccar is recommending CK-4 for certain of its MX diesels in Kenworth and Peterbilt trucks and will release specifics on use of FA-4 early next year. “For enhanced model year 2017 Paccar MX-13 and MX-11 engines, the recommended MX oil service fill is CK-4 oil to provide the greatest reliability with a high level of fuel economy,” says Landon Sproull, Paccar vice president.
“Paccar continues to evaluate usage of FA-4 oil to support enhanced fuel economy and will provide applicability guidance by the start of 2017 after the oils are commercially available and significant durability testing ensures that our best in class B10 engine life reliability of 1 million miles is maintained,” he adds.
John Moore, Volvo Trucks’ product marketing manager - powertrain, says the OEM has issued its own lubricant spec, VDS4.5, which is “a version of the API CK-4 standard, but with higher performance requirements proven by more rigorous testing. This oil was introduced in September as the factory fill in all of our engines and is backward-compatible to legacy engines. Some, but not all, CK-4 oils will meet VDS4.5.” Extended oil drain intervals are available as soon as the customer starts using oil meeting the VDS4.5 standard, he says.
Mack Trucks also released its own oil specification, Mack EOS-4.5, in September, and oils meeting this standard are now used as the factory fill in its GHG 2017 engines, says Scott Barraclough, Mack technology product manager. “These oils are highly recommended for our GHG 2017 engines and can also be used in all Mack engines built since 2007. The Mack EOS-4.5 standard is based on API CK-4, but undergoes additional testing and meets higher performance levels. Some CK-4 oils will meet the Mack EOS-4.5 standard, but not all.”
Cummins also has its own spec. CK-4 oil must meet the engine maker’s new CES 20086 spec while FA-4 oil must meet its new CES 20087 spec, according to Mario Sanchez-Lara, director of on-highway marketing communications.
“For the past two years, Cummins has been working diligently to understand the effects of CK-4 and FA-4 oils on our engines,” Sanchez-Lara says. He advises that CK-4 (CES 20086) oil should be used in all engines where CJ-4 was previously recommended and it can be used as the normal fill and top-off on older engines. It will be the recommended oil for all Cummins engines using ultra low sulfur diesel. He notes that CJ-4 oils can still be used during the transition period, which is expected to run through mid-2017.
“FA-4 (CES 20087) is a new low-viscosity oil that has potential fuel economy benefits, but may not be compatible with all engines,” Sanchez-Lara explains. “The lower dynamic viscosity – how the oil performs at high temperature and shear – leads to thinner oil film thickness and may reduce friction within the engine, possibly creating an incremental gain in fuel economy depending on the duty cycle.”
Cummins will make an individual decision for each on-highway engine on which oil category it recommends and update each owner’s manual accordingly. It has already determined that FA-4 (CES 20087) 10W-30 oil is compatible for use in on-highway versions of its 2017 X15 engine platform after performing several thousand hours of validation testing.
“As they transition to CK-4 or FA-4 oils, fleets should work closely with their lubricant supplier to ensure they choose the right lubricant based on specific engines and common operating conditions,” says Paul Cigala, ExxonMobil applications engineer for commercial vehicle lubricants.
Oil drain intervals
As to the third question, Cummins has developed a program to leverage the extended-drain capability of CK-4 and FA-4.
“To make the best use of these new oil categories and their advanced chemistry, our new OilGuard program uses engine control module data, advanced data analytics and analytical chemistry technology to define a fleet-specific oil drain interval,” says Sanchez-Lara. “Qualifying customers may see drain intervals of 80,000 miles or more, depending on their oil selection and duty cycle.”
Lube suppliers, of course, are also valuable resources on service recommendations. “Before considering oil drain optimization, we’d suggest that fleets take advantage of our Mobil Serv Lubricant Analysis and have at least two or three oil drains using the OEM recommended intervals,” says ExxonMobil’s Cigala. “This will help set an appropriate baseline to evaluate engine performance with the new oils and determine if an optimized oil drain interval program can be started.”
Dan Arcy, global OEM technical manager for Shell, says that “even in current engines, there should be opportunities to increase drain intervals when using CK-4 oil. It’s worth looking into for the cost savings.
“Some engine makers have indicated their standard intervals will change, while others set them fleet-by-fleet,” he continues. “And engine suppliers may adjust their recommendations going forward.” Arcy adds that the rollout of the two categories is a “great opportunity for fleets to reassess their engine oil in terms of how it might help lower overall operating costs.”
“Both CK-4 and FA-4 engine oils will provide extended drain capabilities similar to their API CJ-4 predecessors,” says Petro-Canada’s Humphrey. “The new oils are set to be more robust and resistant to oxidation, which may mean that with proper oil filtration, longer oil drain intervals may be achieved. With proper used oil analysis, drains can be extended within certain limits. We recommend fleets consult their OEM manual to ensure they are following the proper recommendations.”
Chevron’s Badal says he expects there will be a “trend of engine manufacturers to allow increasing maximum drain interval specs for CK-4 and FA-4 in line with their OE specifications.” For instance, as noted above, Volvo already has announced it will allow extended oil drain intervals for customers in its engines using oil meeting the Volvo VDS4.5 standard.
In the meantime and going forward, Badal says fleets “really have to talk to their OEM or oil vendor.
“This ain’t CJ-4 anymore,” he adds. “With the CK-4 and FA-4 categories, fleets have a lot of oil choices to get educated about.”