1998 Chevrolet Astro Owner's Manual - Page 374
1998 Chevrolet Astro Manual
Page 374 highlights
Long Tripmighway Maintenance Schedule 100,000 Miles (I 66 000 km) 0 Inspect spark plug wires. I DATE I An Emission Control Service. 0 Replace spark plugs. An Emission Control Service. 0 If you haven't used your vehicle under severe service conditions listed previously and, therefore, haven't changed your automatic transmission fluid, change both the fluid and filter. 0 Inspect Positive Crankcase Ventilation (PCV) valve. An Emission Control Service. 150,000 Miles (240 000 km) 0 Drain, 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, pressure condenser, capneck.test and Pressure the cooling system and pressurecap. An Emission Control Service. DATE I I I 7-40