1999 Buick Riviera Owner's Manual - Page 331

yellowblue Long Trip/Highway Scheduled Maintenance for any damage. Replace parts as needed. An Emission Control Service. (See footnote[.) j For supercharged engines only: Check the supercharger oil level and add oil as needed (or every 36 months, whichever occurs first). See "Recommended Fluids and Lubricants" in this section. An Emission Control Service. (See footnote[.) j Rotate tires. See "Tire Inspection and Rotation" in the Index for proper rotation pattern and additional information. (See footnote +.) j Replace air cleaner filter. An Emission Control Service. j Inspect fuel tank, cap and lines for damage or leaks. Inspect fuel cap gasket 97,500 Miles (162 500 km) j Change engine oil and filter (or every 12 months, whichever occurs first). An Emission Control Service. j Lubricate chassis components (or every 12 months, whichever occurs first). (See footnote #.) j Rotate tires. See "Tire Inspection and Rotation" in the Index for proper rotation pattern and additional information. (See footnote +.) DATE ACTUAL MILEAGE SERVICED BY: 7-29