ACEA - European Standard

Definition about quality of motor oils

European Standard for car engine oils

For European vehicles sold in the US, there is a further set of criteria, the ACEA classification. Some oil manufacturers include ACEA classification on their oils in addition to the SAE viscosity classification. Modern engines have very tight tolerances and it’s essential that the recommended grade of oil is used, especially with European vehicles. When the correct specification oil cannot be found, it should be purchased directly from the vehicle manufacturers to avoid the possibility of engine failure.

The codes look like this:

A: petrol engines

B: diesel engines of cars, light commercial vehicles

A1, B1: standard quality, normal intervals, but: *HTHS-viscosity lowered

A2, B2: standard quality, normal drain intervals

A3, B3: high performance oil, extended intervals are possible

A4: (reserved for vehicles with petrol direct-injection)

B4: similar to B3, but also for diesel direct-injection engines

A5, B5: similar to A3 or B4, but: HTHS-viscosity lowered

The A refers to petrol and the B to diesel engines. Some oil manufacturers include ACEA classification on their oils in addition to the SAE viscosity classification.

*High-Temperature-High-Shear-viscosity

C: petrol and diesel engines with exhaust after treatment

C1: is suitable for catalytic converter an diesel with particulate filter (DPF), low saps & fuel economy, HTHS viscosity is lowered

C2: is suitable for catalytic converter an diesel with particulate filter (DPF), mid saps & fuel economy, HTHS viscosity lowered

C3: is suitable for catalytic converter an diesel with particulate filter (DPF), mid saps

C4: is suitable for catalytic converter an diesel with particulate filter (DPF), low saps

E: diesel engines of heavy commercial vehicles

The value stands for different performance categories:

E2: normal use, normal drain intervals

E3: heavy use, longer drain intervals possible

E4: very heavy use, longer drain intervals possible

E5: similar to E3; also tested for American engines