Demands for reduced fuel consumption and greenhouse gas (GHG) emissions have led the automobile manufacturers to invest in advanced powertrain designs. These designs include downsized, turbocharged engines with direct fuel injection, which produce the same power as larger engines, resulting in higher specific output and thus greater stress on the engine oil.
Engine oil specifications are regularly upgraded to reflect the latest engine hardware and its needs. ILSAC GF-6, the next global gasoline engine oil specification for vehicles from U.S. and Japanese manufacturers, will be comprised of six newly developed engine tests that will promote enhanced lubricant performance. In addition, GM released their second-generation dexos 1™ specification in December 2014 to meet their new engine hardware and performance needs. Most notably, both GF-6 and dexos 1™ second gen specifications include an engine test to minimize the occurrence of Low Speed Pre-ignition (LSPI) phenomena observed in turbocharged gasoline direct-injection engines.
Pre-ignition control is just one of many areas in which a modern engine lubricant must perform. Striking a balance between LSPI robustness and deposit and oxidation control, wear protection, and fuel economy will be key to formulating engine oils for the future. This presentation will briefly review the evolution of API engine oil specifications and their impact on engine oil development. In addition, a holistic view of the development of next generation ILSAC engine oils will be presented. Emphasis will be placed on successful development efforts to mitigate LSPI, while providing insights on other key performance tests.