2002 Chevrolet Corvette Owner's Manual - Page 259

NOTICE: When adding coolant, it is important that you use only DEX-COOLR (silicate-free) coolant. If coolant other than DEX-COOL is added to the system, premature engine, heater core or radiator corrosion may result. In addition, the engine coolant will require change sooner -- at 30,000 miles (50 000 km) or 24 months, whichever occurs first. Damage caused by the use of coolant other than DEX-COOLR is not covered by your new vehicle warranty. How to Add Coolant to the Coolant Surge Tank If you haven't found a problem yet, check to see if coolant is visible in the surge tank. If coolant is visible but the coolant level isn't at the FULL COLD mark on the coolant surge tank, add a 50/50 mixture of clean, drinkable water and DEX-COOLR coolant at the coolant surge tank, but be sure the cooling system, including the coolant surge tank pressure cap, is cool before you do it. See "Engine Coolant" in the Index for more information. 5-14