Since being introduced in 1996, the ACEA Oil Sequences have historically provided a baseline of performance for service-fill engine lubricants suitable for the majority of the European vehicle fleet. As we move forward, ACEA will be of even greater importance as the OEM engine hardware continues to expand into global markets.
The Light-Duty Sequences consist of detailed sets of specifications for light-duty diesel and gasoline engines, with differentiations for those with and without aftertreatment technology such as particulate filters and catalytic converters. For each engine category, the specifications encompass a range of performance levels, enabling lubricant manufacturers to self-certify their products against the standards that ACEA members demand.
The ACEA 2016 Light-Duty Oil Sequences incorporated significant increases in required performance from ACEA 2012, with the replacement of obsolete tests and removal of the A1/B1 category. The C5 category was introduced for aftertreatment compatibility that covers 0W-20 and 5W-20 lubricants meeting an HTHS (high temperature high shear) viscosity of 2.9cP to 2.6cP. Totaling eight categories, these specifications demanded improved robustness from automotive engine lubricants. They focused heavily on biodiesel compatibility due to increased usage within the market, ensuring continued protection from serious engine wear, oxidation and the formation of deposits.
What’s Next for the ACEA Light-Duty Oil Sequences?
ACEA has now begun to compile the next version of the Oil Sequences, with the goal being to release these new specifications in December 2018, although this date is not yet confirmed. The ACEA 2018 Light-Duty Oil Sequences will reflect the ever-changing demands placed on lubricants, including the introduction of new engine technology and the challenges facing present-day high-performance engines. These factors continue to influence new lubricant performance tests and drive the ACEA categories to adapt in order to satisfy the needs of an evolving market.
Within the Light-Duty Oil Sequences, the A/B categories are designed for gasoline and diesel engines requiring a high Sulphated Ash, Phosphorous & Sulphur (SAPS) lubricant. To maintain the continued suitability of lubricants within the market for the current vehicle fleet, the A3/B3 specification typically used within older vehicles could become obsolete, replaced by amendments to the A3/B4 specification.
Addressing the increasingly significant concern of low-speed pre-ignition (LSPI) within gasoline direct injection (GDI) engines, we may see the introduction of a new A/B category A6/B5, which incorporates new chain wear and LSPI testing. LSPI occurs when the fuel-air mixture within the combustion chamber ignites too early, resulting in high in-cylinder pressure potentially leading to engine knock and even catastrophic engine failure.