1996 Chevrolet Blazer Owner's Manual - Page 343

Short Trip/City Maintenance Schedule 100,000 Miles (166 000 km) 0Drain, flush and refill cooling system (or every 60 months since last service, whichever occurs first). See "Engine Coolant" in the Index for what to use. Inspect hoses. Clean radiator, condenser, pressure cap and neck. Pressure test cooling system and pressure cap. An Emission Control Service. - In hilly or mountainous terrain. - When doing frequent trailer towing. - Uses such as found in taxi, police or delivery service. Ifyou donot use your vehicle under anyof these conditions,the fluid andjilterdo not require changing. Manual transmission fluid doesn't require change. 3- 0Inspect spark plug wires. An Emission Control Service. 0Inspect Positive Crankcase Ventilation ( P c v ) valve. An Emission Control Service. 0Replace spark plugs. An Emission Control Service. 0Change 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 O F (32°C) or higher. 7-31