2006 Subaru Impreza Owner's Manual - Page 290

Maintenance and service 11-11 -30 -20 -10 0 -20 0 10 20 30 40 eas with very high temperatures, or used for heavy-duty applications such as towing a trailer, use of oil with the following grade and viscosities is recommended. API classification SM (or SL): SAE viscosity No.: 30, 40, 10W-50, 20W-40, 20W-50 20 40 60 80 100 5W-30* 10W-30, 10W-40 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. ILSAC Certification Mark (Starburst Mark) B00014 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. Use only engine oil with the recommended grade and viscosity. SAE viscosity No. and applicable temperature *: 5W-30 is recommended. B00522 You can use synthetic engine oil that meets the same requirements given for conventional engine oil. When using synthetic oil, you must use oil of the same classification, viscosity and grade shown in this owner’s manual, and must follow the oil and filter changing intervals shown in the maintenance schedule. Synthetic oil If the vehicle is used in desert areas, in ar- Recommended grade and viscosity under severe driving conditions