Editing Oil Labelling Explained (section)

==ACEA==

This is the European equivalent of API (US) and is more specific in what the performance of the oil actually is. A = Petrol, B = Diesel and C = Catalyst compatible or low SAPS (Sulphated Ash, Phosphorus and Sulphur).

Unlike API the ACEA specs are split into performance/application catagories as follows:

{| border="1" cellpadding="5" cellspacing="0"
|-
|A1||Fuel economy petrol
|-
|A2||Standard performance level (now obsolete)
|-
|A3||High performance and/or extended drain
|-
|A4||Reserved for future use in certain direct injection engines
|-
|A5||Combines A1 fuel economy with A3 performance
|- style="background:silver"
| colspan="2" |
|-
|B1||Fuel economy diesel
|-
|B2||Standard performance level (now obsolete)
|-
|B3||High performance and/or extended drain
|-
|B4||For direct injection car diesel engines
|-
|B5||Combines B1 fuel economy with B3/B4 performance
|- style="background:silver"
| colspan="2" |
|-
|C1-04||Petrol and Light duty Diesel engines, based on A5/B5-04 low SAPS, two way catalyst compatible.
|-
|C2-04||Petrol and light duty Diesel engines, based on A5/B5-04 mid SAPS, two way catalyst compatible.
|-
|C3-04||Petrol and light duty Diesel engines, based on A5/B5-04 mid SAPS, two way catalyst compatible, Higher performance levels due to higher HTHS.
|}

Note: SAPS = Sulphated Ash, Phosphorous and Sulphur.

Put simply, A3/B3, A5/B5 and C3 oils are the better quality, stay in grade performance oils.