1995 Buick Riviera Owner's Manual - Page 285

I Maintenance Schedule I I 30,000 Miles (50 000 km) (Continued) 33,000 Miles (55 000 km) 0Change engine oil and filter (or every 3 months, whchever occurs first). An Emission Control Service. I Rotate tires. See "Tire Inspection and J Rotation" in the Index forproper rotation pattern and additional information. I I I DATE MILEAGE ACTUAL SERVICED BY: DATE MILEAGE ACTUAL SERVICED BY: 7-12