About API SN Plus
What is ILSAC API SN and how does it compare to other proposals to improve GF-5 and meet the performance needs of TGDI engines?
API SN PLUS is a new industry specification proposed by the OEM’s, introducing the additional performance demand of pre-ignition protection to enhance the current GF-5 category. This latest industry proposal is a smaller change to GF-5 than recently considered by Ford for the change to their specifications, Ford WSS-M2C-945A/946A/947A, which would have introduced a requirement for both pre-ignition and timing chain wear. Notably, Afton designed its solution to provide a broader performance enhancement for our API SN PLUS with improvements in pre-ignition, wear, cleanliness and fuel economy. The most significant aspect of this proposal is that it will be an official ILSAC category, ahead of GF-6, and so will require testing to be completed in accordance with the industry codes-of-practice in order to support a licensed ILSAC claim.What is different about API SN PLUS?
ILSAC have asked the industry to define this new category to provide pre-ignition protection for their latest TGDI designs by introducing the Ford LSPI test, under development for inclusion in GF-6, with a maximum limit of 5 pre-ignition events. This proposed pre-ignition limit is in line with the anticipated performance demands of the GF-6 category, but would need to be demonstrated in a registered test according to the requirements of the industry code. All other performance requirements within GF-5 PLUS are the same as current GF-5. In addition, ILSAC have asked for the inclusion of the 0W-16 grade into API SN Plus. Currently the SAE 0W-16 grade has only been established within the API SN performance specification, but this proposal may extend the recommended viscosity grades within the ILSAC specification.
Does the market really need it?
TGDI engine technology currently accounts for over 50% of new vehicle registrations and the majority of these designs are also turbocharged. This is rapidly changing the landscape of the NA car park, which was a primary factor behind the development of the GF-6 specification. TGDI engines have both unique performance demands, such as pre-ignition protection, and increased operational severity. With additional delays in the completion of GF-6, the needs of these engines, which now account for a significant percentage of vehicles on the road, can only really be met with an optimized product option such as API SN PLUS.What is the proposed timing for API SN PLUS?
ILSAC have indicated that they would like the new API SN PLUS category to be defined for first license use from January 1, 2018. It is anticipated that the new category will be adopted by all ILSAC members – as all are acting in consensus in the request for API SN PLUS – and replace existing GF-5 products in their lubricant recommendations for certain engines.What needs to be done in order to finalize API SN PLUS?
In order for the LSPI test to be included in a revised industry category, the test has to be introduced into the industry codes. All tests have to be completed under the code registration guidelines, and currently the LSPI test cannot be run as a registered test. All data obtained to date is therefore essentially only a demonstration of capability and once registration is allowed program testing will have to be repeated to support an ILSAC API SN PLUS claim.In addition to the LSPI test being approved for registration, the industry also has to determine appropriate minor modification guidelines to apply to the LSPI test and define acceptable BOI and VGRA read-across guidelines. An industry test matrix has been defined and funded to allow the industry to generate LSPI data in order to develop appropriate BOI and VGRA guidelines and once these are in place the oil and additive industry will likely require a period for technology demonstration testing prior to API SN PLUS introduction.
For more information on LSPI, click here.