2007 Subaru Impreza Owner's Manual - Page 303

Maintenance and service 11-11 & Recommended grade and viscosity Oil grade: ILSAC GF-4, which can be identified with the ILSAC certification mark (Starburst mark) or API classification SM with the words "ENERGY CONSERVING" capabilities These recommended oil grades can be identified by looking for either or both of the following marks displayed on the oil container. ILSAC Certification Mark (Starburst Mark) SAE viscosity No. and applicable temperature *: 5W-30 is preferred. In choosing an oil, you want the proper quality and viscosity, as well as one that will add to fuel economy. The following table lists the recommended viscosities and applicable temperatures. When adding oil, different brands may be used together as long as they are the same API classification and SAE viscosity as those recommended by SUBARU. Engine oil viscosity (thickness) affects fuel economy. Oils of lower viscosity provide better fuel economy. However, in hot weather, oil of higher viscosity is required to properly lubricate the engine. CAUTION Use only engine oil with the recommended grade and viscosity. API Service label 1) Indicates the oil quality by API designations 2) Indicates the SAE oil viscosity grade 3) Indicates that the oil has fuel saving - CONTINUED -