1997 GMC Sonoma Owner's Manual - Page 339

I Short TripKity Maintenance Schedule I 78,000 Miles (130 000 km) 0Change engine oil and filter (or every 3 months, whichever occurs first). An Emission Control Service. 0Inspect air cleaner filter if you are driving in dusty conditions. Replace filter if necessary. An Emission Control Service. (See footnote?.) Check readfront axle fluid level and add fluid as needed. Check constant velocity joints and axle seals for leaking. (See footnote **.) 0Lubricate chassis components (or every 3 months, whichever occurs first). (See footnote #.) i ACTUAL MILEAGE 1- 1 (Continued) 7-29