1998 GMC Suburban Owner's Manual - Page 395

1 Long Tripklighway Maintenance Schedule '-- Gasoline Engines 1 0 Check rear/front axle fluid level and add fluid as needed. Check constant velocity joints and axle seals for leaking. (See footnote':">.) 0 Vehicles With GVWR Above 8,500 Ibs. Only: Inspect shields and underhood insulation for damage or looseness. Adjust or replace as required. This isLL Noise Emission Contrvl Service. AppliccrblcJ only to vehicles sold irl the United States. 0 Rotate tires. See "Tire Inspection and Rotation" i n the Index for proper rotation pattern and additional information. (See footnote +.) 50,000 Miles (83 000 km) 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. - I n hilly or mountainous terrain. - When doing frequent trailer towing DATE 7-31