KnowledgebasE Article

Understanding ACEA oil and lubricant standards

Much like the American Petroleum Institute (API) in the United States, Europe has its own regulatory body - the Association des Constructeurs Européens de l’Automobile (ACEA). The ACEA sets forth oil specifications that are often stricter and more comprehensive than their American counterparts.

The ACEA classifies oils into three main groups – A/B for petrol (A) and light-duty diesel (B) engines, C for catalyst-compatible oils used in light-duty vehicles, and E for heavy-duty diesel engines. Here’s a breakdown of each classification:

A/B Classifications

The A/B groups specify the oil standards for petrol and diesel engines, primarily used in passenger cars and light commercial vehicles. The classifications range from A1/B1 to A7/B7, with each category catering to different engine designs and capabilities.

For example, A3/B3 classification refers to stable, stay-in-grade oils designed for high-performance engines and extended drain intervals. On the other hand, A7/B7 oils are formulated for use at extended drain intervals in passenger cars and light-duty petrol & DI diesel engines. They provide low-speed pre-ignition and wear protection for turbocharged petrol DI engines and turbocharger compressor deposit (TCCD) protection for modern DI diesel engines.

C Classifications

The C group is designed for catalyst-compatible oils usually used in light-duty vehicles with emission control systems such as Three-Way Catalysts (TWC) and Diesel Particulate Filters (DPF). These oils are Low to Mid-SAPS (Sulphated Ash, Phosphorous, and Sulphur), indicating that they have lower concentrations of these elements to prevent catalyst poisoning and particulate filter blocking.

For instance, C2 oils are stay-in-grade oils for vehicles fitted with DPFs & TWCs, designed for high-performance engines requiring low friction, low viscosity, and mid-SAPS oils.

E Classifications

The E group caters to heavy-duty diesel engines. These oils, ranging from E2 to E9, are designed for use in various diesel engines in severe heavy-duty service and extended drain intervals. They’re compatible with emission requirements such as Euro 3, Euro 4, Euro 5, and Euro 6.

For example, E4 oils are stable, stay-in-grade oils designed for significantly extended drain intervals, suitable for Euro 3, Euro 4 & Euro 5 engine emission requirements. They are typically synthetic or predominantly synthetic.

While the ACEA provides the fundamental standards, some manufacturers also have their specifications, like Mercedes Benz with MB 229.31/229.51/229.52, BMW Longlife-04, and VW 507 00.