2007 Subaru Outback Owner's Manual - Page 401

GAS STATION REFERENCE Fuel Use unleaded gasoline with an octane rating of 91 AKI or higher. Regular unleaded gasoline with an octane rating of 87 AKI or higher may be used. However for optimum engine performance and driveability, it is recommended that you use 91 AKI or higher grade unleaded gasoline. You may experience reduced output, poor accelerator response, and reduced fuel economy when using gasoline with an octane rating lower than 91 AKI, depending on your driving habits and conditions. If you experience any of these conditions while using a lower octane rated fuel, you may want to return to using 91 AKI octane rated fuel as soon as possible. Additionally, if your vehicle knocks heavily or persistently, or if you are driving with heavy loads such as when towing a trailer, the use of 91 AKI or higher grade unleaded gasoline is required. Fuel octane rating This octane rating is the average of the Research Octane and Motor Octane numbers and is commonly referred to as the Anti Knock Index (AKI). Refer to "Fuel" section in this manual. Fuel capacity 16.9 US gal (64 liters, 14.1 Imp gal) Engine oil Use only API classification SM with the words "ENERGY CONSERVING" and the ILSAC certification mark (starburst mark) displayed on the container. Engine oil capacity 5.8 US qt (5.5 liters, 4.8 Imp qt) Cold tire pressure Tire size Wheel size Pressure Front Rear Rear at trailer towing Temporary spare tire Size Pressure P255/55R18 104H 18 × 8JJ 33 psi (230 kPa, 2.3 kgf/cm2) 32 psi (220 kPa, 2.2 kgf/cm2) 32 psi (220 kPa, 2.2 kgf/cm2) T165/80R17 60 psi (420 kPa, 4.2 kgf/cm2)