2004 Buick Regal Owner's Manual - Page 230

How to Check and Add Oil Park the vehicle on a level surface. Check oil only when the engine is cold. Allow the engine to cool two to three hours after running. Engine Air Cleaner/Filter See Engine Compartment Overview on page 5-12 for location of engine air cleaner/filter. {CAUTION: If you remove the supercharger oil fill plug while the engine is hot, pressure may cause hot oil to blow out of the oil fill hole. You may be burned. Do not remove the plug until the engine cools. 1. Clean the area around the oil fill plug before removing it. 2. Remove the oil fill plug. 3. The oil level is correct when it just reaches the bottom of the threads of the inspection hole. 4. Replace the oil plug with the O-ring in place. Tighten to 88 lb-in (10 Y). When to Inspect the Engine Air Cleaner/Filter Inspect the air cleaner/filter at every oil change and replace at the first oil change after 25,000 miles (40 000 km). How to Inspect the Engine Air Cleaner/Filter To inspect the air cleaner/filter remove it from the vehicle and lightly shake the filter to release loose dust and dirt. If the filter remains "caked" with dirt, a new filter is required. 5-22