1997 GMC Sonoma Owner's Manual - Page 344

I Short TripKity Maintenance Schedule CI Change engine oil and filter (or every 3 months, whichever occurs first). An Emission Control Service. I [7 Check readfront axle fluid level and add 96,000 Miles (160 000 km) fluid as needed. Check constant velocity joints and axle seals for leaking. (See footnote ** .) Rotate tires. See "Tire Inspection and Rotation" in the Index for proper rotation pattern and additional information. (See footnote +.) Lubricate chassis components (or every 3 months, whichever occurs first). (See footnote #.) DATE ACTUAL MILEAGE SERVICED B Y 7-34