The Single Technology Matrix Process for Fully Formulated Engine Oil Capability Testing

The American Petroleum Institute’s (API) Single Technology Matrix (STM) is a data-based, Virtual Testing process and protocol (utilizes test data, characteristics and features of base stocks and blends coupled with statistical methods and analysis) used to predict the performance capability of a specific engine oil additive technology in a single specified base oil, in a given engine test. The concept was first introduced in 2002, codified and implemented by API in 2007, and updated in 2022. The previously published advantages of STM in the proof-of-performance of engine oils, remain relevant. These advantages include a data space focused on interpolation, documented statistical analysis protocol, limitation to a specific formulation, flexibility in understanding complicated, interactive, or non-linear technology and base oil relationships, and timeliness. There have been numerous changes to, and in, the engine oil industry since the introduction of STM in 2007. These include advances in base stock refining practices, improvement in additive technology, lower viscosity oils, supply chain issues due to local and global disruptive events, test capacity issues due to stalled industry growth and increased regulatory practices. The enhancement of the STM process for both 2022 and beyond is warranted and justified in response to these changes. This paper serves as an educational tool on the STM concept to enhance understanding and perspective of the current concept not provided elsewhere, as well as the improvement of the process to address the evolving performance testing and base oil characterization needs of the future. It is an important first step in the necessary continuous dialogue on the protocol and the future data needs to support the protocol.