2002 GMC Sonoma Owner's Manual - Page 403

Short Trip/City Scheduled Maintenance 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 +.) 48,000 Miles (80 000 km) DATE ACTUAL MILEAGE SERVICED BY: 50,000 Miles (83 000 km) j If you haven't used your vehicle under severe service conditions listed previously and, therefore, haven't changed your automatic transmission fluid, change both the fluid and filter. Manual transmission fluid doesn't require change. DATE ACTUAL MILEAGE SERVICED BY: 7-19