The average age of five engine performance tests used for the API CK-4 category is 19 years, Cory Koglin, OEM relationship manager for lubricant additives manufacturer Afton Chemical, told Active Communication International‘s U.S. Base Oils and Lubricants Summit on Aug. 29. These include three wear tests – the Mack T12, the Cummins ISM and the Roller Follower Wear test; the Cat Single Cylinder deposits test; and the Mack T11 soot handling test.

“The tests are quite old, and those same five tests also are used in every single active [heavy-duty] category today,” Koglin noted. “We’re using up hardware for every single category as we certify to get all those API specifications. The challenge in the industry here is we are at risk of not having these tests to keep the categories alive, both for older categories and current categories, including CK-4 and FA-4.”

This risk is greater for certain types of test categories where only one option is available, such as soot handling, with only the Mack T11 test available; or where only two are available, such as deposits, with only the CAT Single Cylinder and C13 Deposits tests available. He pointed out, “It’s less of a concern in the wear test category, which has four tests available – the Mack T12, the Cummins ISB, the Cummins ISM and the Roller Follower Wear. However, if you lose a soot handling test, there isn’t a backup or secondary test,” Koglin said. “So it does become a pretty big risk.”

Potential solutions for the challenge of maintaining older categories, he suggested, could include re-evaluating the need for existing heavy-duty engine oil categories and starting replacement test development as soon as possible.

“[ILSAC] GF-6 was a real challenge, with replacement tests and new tests,” Koglin noted. “Ideally, I think if we learned our lesson, we won’t repeat the same thing with the next heavy-duty category, PC12, when and if that comes along.”

He said it could be especially important in preparation for future regulations and lower viscosities to consider investing in some new tests for the new categories, specifically ones that are going to use lower-viscosity heavy-duty engine oils.

Another key challenge is the introduction of a new, lower-viscosity category such as FA-4. Koglin noted that in December 2018 API reported that only 100 companies had obtained licenses for FA-4, compared to 1,567 for CJ-4, 1,218 for CI-4, 1,047 for CK-4 and 377 for CH-4.

Factors hindering FA-4 approvals to date include limited acceptance by OEMs, limited backwards compatibility and auxiliary power unit compatibility concerns. “Because most fleets have mixed OEM engines and mixed trucks, they are going to use the oil they can use in the entire fleet, which wouldn’t be FA-4,” he explained.

Detroit Diesel adopted FA-4 and deemed it fully backwards compatible with its engines back to 2010, but Koglin noted that other OEMs have said they’ll recommend FA-4 only for newly introduced engines that are only one or two years old. “Again, vehicles with fleets with mixed ages for their engines are going to find it difficult to adopt FA-4 into their fleet,” he said. “They’re going to fall back to CK-4, even though they may want to use FA-4 to improve fuel economy.”

Auxiliary power concerns relate to truck units with refrigeration units or a small, auxiliary diesel engine used for hoteling power. “They were never validated on FA-4, so if a driver or maintenance facility has to top off oil, they are not going to want to have FA-4 to top off these auxiliary power units and risk an issue with those units,” he said. “So again they’re going to fall back to CK-4.”

Another challenge for FA-4 involves maintenance facilities, which generally have one tank that pipes heavy-duty engine oil to all the service bays. “All these add up to not having FA-4 in those single tanks, so again you’re going to default back to likely a 10W-30 or 15W-40 CK-4 style of oil,” Koglin said.

He acknowledged that introducing a new, lower-viscosity category is very challenging and said its clear that the industry did a very good job of trying to advertise FA-4 and its differences. “However, I think it’s becoming clear we almost have to do a better job if were going to do this again in the future,” he added.

Koglin suggested new, lower-viscosity categories could benefit from earlier collaboration on efforts to raise awareness. “Perhaps industry can actually come up with a task force with the OEMs, the marketers, and start even earlier than they did with FA-4 to start education, to get feedback from the commercial vehicle sector on how these oils will be accepted, so we can move those into the marketplace sooner and see higher volumes of that,” he said.