1998 GMC Sonoma Owner's Manual - Page 345

Short Trip/City Maintenance Schedule I 0 Change automatic transmission fluid and filter if the vehicle is mainly driven under one or more of these conditions: - 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 crny of these coditions, clmnge tlze.flr.tid andfilter every 50,000 miles (83 000 km). 0 Inspect air cleaner filterif you are driving in dusty conditions. Replace filter if necessary. An Emission Control Service. (See footnote?.) 0 Check readfront axle fluid level and add fluid as needed. Check constant velocity joints and axle seals forleaking. (See footnote **.) 78,000 Miles (130 000 knz) 0 Change engine oil and filter (or every 3 months, whichever occurs first). An Ernissiorz Control Service. 0 Lubricate chassis components (or every 3 months, whichever occurs first). (See footnote#.) DATE (Continued) 7-23