1997 Buick Riviera Owner's Manual - Page 349

Long TriplHighway Maintenance Schedule 90,000 Miles (150 000 km) 0Change engine oil and filter (or every For supercharged engines only: Check the supercharger oil level and add oil as needed 12 months, whichever occurs first). (or every 36 months, whichever occurs An Emission Control Service. first). See "Recommended Fluids and 17 Lubricate chassis components (or every Lubricants" i this section. n 12 months, whichever occurs first). An Emission Control Service. (See footnote"f.) (See footnote#.) 0Rotate tires. See "Tire Inspection and Replace air cleaner filter. Rotation" in the Index for proper rotation An Emission Control Service. 0Inspect fuel tank, cap and lines for damage pattern and additional information. (See footnote+.) or leaks. Inspect fuel cap gasket for any damage. Replace parts as needed. An Emission Control Service. (See footnote?.) 7-36