Automakers push API to early spec, but SN testing under pressure

Turbocharged engine manufacturers may get an early supplemental oil specification, but SN is under pressure.

Pressure from automakers has forced the American Petroleum Institute (API) to concede an early date (1st January 2018) for release of the new specification.

Oil on engine block

Oil spec under pressure Image: Commons

What's the urgency? 10 automakers are pressuring the API.

One example is Ford which has 25% of their new models with turbocharged gasoline direct injection (TGDi) enginesĀ  experiencing potentially destructive pre-ignition issues.

A new engine oil formulation is critical in preventing this problem.

The supplemental category is likely to be called an "API SN Plus", which will be identified in the API 'donut', part of the labelling which identifies the oil's performance claims.

API SN Plus will have to meet all the existing requirements of the current ILSAC GF-5. In addition, it will include the Ford LSPI test or, possibly, a GM LSPI test. It will also include all GF-5 viscosity grades plus SAE 0W-16.

However, the API admitted the entire SN specification is under threat because of availability of engine parts and equipment to run key existing tests, including continuous running and towing in high temperature conditions. According to Lubes Report, despite the vote to expedite the API SN Plus spec, the overall testing issue is a major concern for the organisation.