ACEA passenger car motor oil sequences

introduction to european PCMO categories

High quality engine oils and lubricants are formulated to meet the current needs of the automotive industry. High quality lubricants are required to protect modern engines and give them the highest level of reliability. For the European automotive industry, a baseline of engine oil specifications has been developed by ACEA. The ACEA European Oil Sequences define the minimum quality level of service oils as defined and requested by the ACEA members for use in their vehicles. On top of the ACEA European Oil Sequences, OEMs have their own specifications and distinct requirements. Once successfully tested and approved by the respective OEMs, these specific OEM approvals can be added to the ACEA claims.

A/B category

Conventional oils including A7/B7 which are introduced with ACEA 2021.

C2/C3 category

Oils compatible with after-treatment

C5 category

High fuel economy oils compatible with after-treatment

C6 category

ACEA C6 is introduced with new ACEA 2021. It provides additional performance against C5 on LSPI protection, engine chain wear protection and turbocharger deposit control.

A/B category including the new A7/B7

The ACEA A and B categories are designed for high performance gasoline and light duty diesel engines and provide the minimum performance required for many OEM specifications. The ACEA A and B categories are considered conventional oils and are full sulfated ash, phosphorus and sulfur (SAPS) formulations to ensure maximum engine performance and engine protection.


For vehicles without after-treatment systems, it is common to have full SAPS oil recommendations as these vehicles do not use advanced emission systems, which are sensitive to high SAPS levels. These A/B oils are also suitable for regions outside of Europe, for markets with lower fuel quality requirements. Lower fuel qualities (e.g., higher sulfur levels) can contribute to higher SOX levels and particulate matter emissions, where some SOX emissions can be converted in the atmosphere to sulfate particulate matter. The reactive nature of such components can be better controlled by A & B oils with higher SAPS levels to include higher TBN that reduces degradation of the lubricant.


Higher SAPS levels of engine oils are directly related to the additives and additive levels used in engine oils that are providing desirable performance properties including detergency and wear and oxidation protection.


With ACEA 2021 a new A7/B7 category is introduced. It provides additional performance against A5/B5 on LSPI protection, engine chain wear protection and turbocharger deposit control.


Based on OEM interest Oronite expects the main conventional lubricant market will remain based on A3/B4 and in a lesser sense A5/B5.


Typical examples within the Oronite product range: OLOA ® 54100, OLOA® 54120 and OLOA 54050.

C2/C3 categories

Automotive industry trends and governmental regulations are resulting in lower SAPS levels in automotive engine oils. Over the past decades, new car models have been subjected to increasingly more stringent exhaust emission limits. Modern clean cars combine low CO2 emission with low particulate emissions to meet the latest European regulations. To achieve those goals of lower CO2 and particulate emissions, modern cars, gasoline and diesel, are equipped with aftertreatment systems to eliminate most particulate and NOX emissions. To ensure compatibility with aftertreatment devices, the SAPS limits of lubricants have been significantly reduced as they can negatively influence the performance of aftertreatment devices.


That is the main reason why, in addition to the conventional ACEA A/B categories, the ACEA European Oil Sequences also includes the C categories. ACEA C category oils are stable, stay-in-grade engine oils with mid SAPS-level, intended for use as a catalyst compatible oil in vehicles with all types of modern aftertreatment systems. The ACEA C categories were first introduced in the 2004 edition of the ACEA European Oil Sequences. An example is the ACEA C3 category. ACEA C3 oils are top tier lower SAPS lubricants designed for use in high performance gasoline and light duty diesel engines with advanced after treatment systems.


Typical examples within the Oronite product range: OLOA® 54510 and OLOA 54499.

C5 category

European Union (EU) legislation sets mandatory reduced CO2 emission targets for new cars. This legislation is the cornerstone of the EU's strategy to improve the fuel economy of cars sold on the European market.


To meet the continued demands for reduced emission and better fuel economy made by the European requirements, oil also has a significant role to play. As such, ACEA has introduced its ACEA C5 category within ACEA 2016 specifications. This ACEA C5 category involves very low viscosity (high-temperature, high-shear (HTHS) minimum 2.6 mPas) engine oils, providing improved fuel economy. These mid SAPS oils are aftertreatment compatible and intended for use in highly loaded direct-injection gasoline and diesel engines. In addition to delivering high fuel economy, this ACEA C5 specification includes additional tests, such as a test to ensure high oxidation stability and compatibility with bio-fuels


European OEMs have introduced their OEM specific, high fuel economy specifications based on this ACEA C5 claim. In most cases, they have added more requirements to protect their newest, highly loaded, engine technology needed to meet the legislative lower emissions and better fuel economy targets. These additional lubricant requirements include tests to avoid low speed pre-ignition (LSPI), such as in Daimler MB 229.71, and ensure long-drain protection and excellent deposit control as in BMW LL17FE+.


Typical examples within the Oronite product range: OLOA® 54508 and OLOA® 54720.

C6 category

With continued emphasis on CO2 and emissions reduction the OEMs are introducing ever more advanced and sophisticated engine technology. This results in increased power density and higher operating temperatures which can cause oils to degrade sooner, thicken faster, and to make them more prone to form deposits, especially in the hot running parts like the piston ring pack and turbochargers.


That means modern lubricants need to offer improved performance on cleanliness and oxidation stability.


New ACEA C6 based oils provides that additional performance needed for today’s modern engine technology. Next to fuel economy and lower viscosities from the C5 category it additionally provides LSPI protection, engine chain wear protection and turbocharger deposit control.


Typical example with ACEA C6 next to C5 within the Oronite product range: OLOA® 54720.

european oil specs in the middle east