2003 Subaru Impreza Owner's Manual - Page 340

Maintenance and service If you check the oil level just after stopping the engine, wait a few minutes for the oil to drain back into the oil pan before checking the level. Just after driving or while the engine is warm, the engine oil level reading may be in a range between the upper level and the notch mark. This is caused by thermal expansion of the engine oil. To prevent overfilling the engine oil, do not add any additional oil above the upper level when the engine is cold. J Changing the oil and oil filter Change the oil and oil filter according to the maintenance schedule in the "Warranty and Maintenance Booklet". The engine oil and oil filter must be changed more frequently than listed in the maintenance schedule when driving on dusty roads, when short trips are frequently made, or when driving in extremely cold whether. 1. Warm up the engine by letting the engine idle for about 10 minutes to ease draining the engine oil. 2. Park the vehicle on a level surface and stop the engine. 3. Remove the oil filler cap. 1) Drain plug 4. Drain out the engine oil by removing the drain plug while the engine is still warm. The used oil should be drained into an appropriate container and disposed of properly. WARNING Be careful not to burn yourself with hot engine oil. 5. Wipe the seating surface of the drain plug with a clean cloth and tighten it securely with a new seal- CONTINUED - 11-11