2003 Buick Century Owner's Manual - Page 322

100,000 Miles (166 000 km) 0 Inspect spark plug wires. An Emission Control Service. C Replace spark plugs. An Emission Control Service. l 0 Change automatic transaxle fluid and filter 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. - In hilly or mountainous terrain. - When doing frequent trailer towing. - Uses such as found in taxi, police or delivery service. U If you haven't used your vehicle under severe service conditions listed previously and, therefore, haven't changed your automatic transaxle fluid, change both the fluid and filter. 150,000 Miles (240000 km) 0 Drain, flush and refill cooling system (or every 60 months since last service, whichever occurs first). See Engine Coolant on page5-22 for what to use. Inspect hoses. Clean radiator, condenser, pressure cap and neck. Pressure test the cooling system and pressure cap. An Emission Control Service. U Inspect engine accessory drive belt. An Emission Control Service. 6-9