NOTE: These performance charts are primarily designed to demonstrate relative performance within the same industry specification. For example: European Automobile Manufacturers Association (Association des Constructeurs Européens d'Automobiles). The primary automotive standards organization in the European Union, ACEA defines performance specifications for automotive lubricants. 2012 vs ACEA 2016 or American Petroleum Institute. The primary oil and natural gas trade association in the United States. API operates a voluntary licensing and certification program that allows engine oil marketers to use the API Engine Oil Quality Marks if their products meet specific requirements. CJ-4 vs API CK-4. This tool has not been expressly designed to show relative performance between different specifications.