1998 Buick Regal Owner's Manual - Page 284

How to Check and Add Oil Automatic Transaxle Fluid When to Check and Change A good time to check your automatic transaxle fluid level is when the engine oil is changed. ~ ~ A CAUTION: Check oil only when the engine is cold. Allow the engine to cool two to three hours after running. If you remove the supercharger oil plug while fill the engine is hot, pressure may cause hot oil to blow outof the oil fill hole. You may be burned. Do not remove the plug until the engine cools. 1. Clean the area around the oilfill plug before removing it. Change both the fluid and filter every 50,000 miles (83 000 km) if the vehicle is mainly driven under one or more of these conditions: In heavy city traffic where the outside temperature regularly reaches 90°F (32"C) or higher. 0 In hilly or mountainous terrain. When doing frequent trailer towing. Uses such as found in taxi, police or delivery service. 0 0 2. Remove the oil fill plug using a 3/ 16 inch Allen wrench. 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. Torque to 88 lb-in (10 N-m). If you do not use your vehicle under any of these conditions, the fluid and filter do not require changing. See "Scheduled Maintenance Services" in the Index. 6-20