2012 Chevrolet Corvette Owner's Manual - Page 305

Vehicle Care WARNING (Continued) Never turn the cap when the cooling system, including the coolant surge tank pressure cap, is hot. Wait for the cooling system and coolant surge tank pressure cap to cool if you ever have to turn the pressure cap. If coolant is needed, add the proper DEX-COOL coolant mixture directly to the surge tank, but be sure the cooling system is cool before this is done. 10-29 1. When the cooling system, including the coolant surge tank pressure cap and upper radiator hose, is no longer hot, remove the pressure cap. Turn the pressure cap slowly counterclockwise about one-quarter turn and then stop. If a hiss is heard, wait for that to stop. A hiss means there is still some pressure left. 2. Keep turning the pressure cap slowly, and remove it. 3. Fill the coolant surge tank with the proper DEX-COOL coolant mixture until the level inside stabilizes at the FULL COLD mark on the front of the surge tank.