1999 GMC Safari Owner's Manual - Page 333

yellowblue Short Trip/City Scheduled Maintenance - 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. If you do not use your vehicle under any of these conditions, change the fluid and filter every 50,000 miles (83 000 km). j Inspect air cleaner filter if you are driving in dusty conditions. Replace filter if necessary. An Emission Control Service. (See footnote[.) 48,000 Miles (80 000 km) j Change engine oil and filter (or every 3 months, whichever occurs first). An Emission Control Service. j Lubricate chassis components (or every 3 months, whichever occurs first). (See footnote #.) j Check rear/front axle fluid level and add fluid as needed. Check constant velocity joints and axle seals for leaking. (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: 7-17