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API SN Plus: Fast Tracking New Engine Oil Specifications

By Aaron Stone and Vicky Villena-Denton

The patience of Original Equipment Manufacturers (OEMs) has finally run out. Automakers are no longer prepared to wait for ILSAC GF-6 to address concerns about Low Speed Pre-Ignition (LSPI) in a growing fleet of turbocharged vehicles. With turbocharged direct injection (TGDI) engines accounting for an estimated 25% of vehicles sold this year, and still two years remaining until the GF-6 specification with promised LSPI protection arrives, a group of OEMs have taken matters into their own hands — successfully petitioning API for a supplementary passenger car engine oil specification.

Engine oil formulations are critical to preventing the occurrence of LSPI, a phenomenon that can damage and even destroy TGDI engines. On 20 July 2017, Ron Romano, chairman of the ILSAC/Alliance LWG, highlighted the concerns of a group of OEMs in a letter to Kevin Ferrick, senior manager of API’s Engine Oil Licensing and Certification System (EOLCS). Romano, of Ford Motor Company, formally requested API to develop a supplement to the existing ILSAC GF-5 standard. “There is an immediate need for preventive action to reduce/eliminate the occurrence of oil derived low-speed engine pre-ignition,” he wrote. “Due to delays in the development of ILSAC GF-6 we feel it is necessary to incorporate LSPI protection into a category/standard as soon as possible.” The request was also signed by FCA US LLC, Toyota Motor Corp., Mitsubishi Motors Corp., Honda Motor Co. Ltd., Nissan Motor Co., Ltd., General Motors Co., Mazda Motor Corp., Daihatsu Motor Co., Ltd., Subaru Corp. and Suzuki Motor Co., Ltd.

Following consideration at the American Petroleum Institute’s Standards Meeting on 15 August, the organisation voted unanimously to establish a supplemental passenger car engine oil category that addresses LSPI, despite some concern the move would deflect resource and attention away from GF-6. The supplementary category will be called API SN Plus.

OEMs have also requested a change to API SN Resource Conserving as part of the supplement. API SN Plus will cover an array of viscosity grades, including non-traditional resource-conserving, as well as SAE 0W-16 and 5W-16. “Effectively, this category will allow marketers to offer a broader range of viscosity grades,” Ferrick explains. Without Sequence VI-D marketers won’t be able to claim resource-conserving, though Ferrick is conscious of allowing marketers the ability to license products that have demonstrated LSPI protection, even for non-ILSAC viscosity grades like 0W-40. API has recommended the use of the Ford LSPI test to measure low-speed pre-ignition, alongside other tests present in ILSAC GF-5/ API SN. The Ford LSPI test has been approved by ASTM’s Passenger Car Engine Oil Classification Panel for use in the future GF-6 standard, though it is still awaiting ASTM’s approval of the final LSPI test method as of this writing. Products that have passed the General Motors dexos LSPI test will still be required to pass the Ford LSPI test. The GM test is not included in the ACC Code of Practice, and therefore cannot be used to support an API category or supplement. Fast-tracking engine oil specifications is easier said than done. While API’s support for the new supplement, and progress to date, is satisfying for concerned OEMs, expediting this specification still requires a significant volume of work.

API will revise an existing process that covers the development of the API CI Plus diesel standard to include API SN (gasoline). The diesel process has been in place since CI-4 Plus was introduced in 2002. Part of that process is the designation category plus the word Plus. A more generic process could cover passenger car and diesel engine oil and will assist in advancing the development of API SN Plus.

API SN Donut Designs

Romano’s original request was that this supplemental category be available for licensing by 1 January 2018, the Ford Motor Co. representative suggesting the date was achievable with the requisite amount of focus. However, API “hasn’t committed to the January 1st date,” Ferrick told F&L Asia in September. Before a target date can be confirmed there are three critical tests that need to be resolved, he says.

“We are waiting on Ford to tell us when the procedure is finalised and ready for matrix testing,” says Ferrick. In addition, severity issues for the Sequence IIIH need to be resolved and the replacement tests for the Sequence VID, which is in provisional licensing, have to be approved. Romano believes the October ballot for ASTM is achievable for LSPI.

Upon completion of test development, API mandates a ‘waiting period’ when issuing a new standard. Even though this is only a ‘supplement,’ Ferrick maintains a waiting period is necessary “to allow marketers to get their products reformulated, tested and their products out the door for distribution to the different marketing channels.” Typically, the waiting period is 12 months, although this is yet to be confirmed. Even if it can be condensed, the expectation is “a minimum of six months.” Perhaps the more pressing question is… when will the clock actually start?

Even after API SN Plus is live, communicating the new oil to end-users is likely to provide a significant challenge. API has drafted and circulated for comment user language for the new API SN Plus ‘supplement.’ The user language defines the category and will become part of API 1509 — which describes the voluntary API Engine Oil Licensing and Certification System and explains to marketers how different API marks are licensed and displayed for the consumer.

ILSAC has requested the addition of LSPI to API SN, with no change to existing ILSAC GF-5 licenses. “The Starburst will still represent the present ILSAC GF-5 category,” says Romano. ILSAC has proposed that the new supplement’s designation appear in the bottom of the API Donut symbol on back labels.

This poses an entirely new problem for the industry. The API Donut can be anywhere in the package, though is traditionally on the back, meaning “we have to teach people to turn the bottle around” to find out if an oil will cover SN Plus, says Ferrick. Once these oils are available, he admits further outreach will be necessary to educate end users and the industry.

Despite the resource and effort poured into progressing the API SN Plus supplement, and some may say notwithstanding a declining urgency for ILSAC GF-6, ILSAC advised during a Lubricant Standards Group meeting on 14 September that GF-6 will continue without delay — the API SN Plus designation will not impact GF-6 timings. Exactly what those timings are for GF-6 are still not fully understood.

Even without LSPI, GF-6 is still necessary — as it includes tests that are not part of API SN Plus, and are required by OEMs for improved performance while also improving fuel economy.