1998 Chevrolet Express Van Owner's Manual - Page 261

NOTICE: When adding coolant, is important thatyou it (silicate-free) coolant. use onlyDEX-COOL@ If coolant other than DEX-COOL added to is the system, premature engine, heater coreor radiator corrosion may result. In addition, the engine coolantwill require change sooner at 30,000 miles (50 000 km) or 24 months, whichever occurs first. Damage caused the by is not use of coolant other than DEX-COOL@ covered by your vehicle warranty. new What to Use Use amixture of one-half clean water (preferably distilled) and one-halfDEX-COOL@coolant which won't damage aluminum parts. If youuse this mixture, you don't need to add anything else. -- I Adding only plain water to your cooling system can be dangerous. Plainwater, or some other liquid like alcohol, can before the proper boil coolant mixture will. Your vehicle's coolant warning systemis set for the proper coolant mixture. With plain water the wrong mixture, or your engine could too hot but get you wouldn't get the overheat warning. Your engine could catch fire andyou or others could be burned. Use a 50/50 mixture of clean water and DEX-COOL@coolant. 6-22