2007 Chevrolet Impala Owner's Manual - Page 331

When the engine is cold, the coolant level should be at or above the cold fill line on the coolant recovery tank. To check the coolant level, look for the cold fill line on the side of the coolant recovery tank that faces the engine. If the level is not correct, there may be a leak at the pressure cap or in the radiator hoses, heater hoses, radiator, water pump, or somewhere else in the cooling system. If there seems to be no leak, with the engine on, check to see if the electric engine cooling fans are running. If the engine is overheating, the fans should be running. If the fans are not running, your vehicle needs service. Notice: Engine damage from running your engine without coolant is not covered by your warranty. See Overheated Engine Protection Operating Mode on page 329 for information on driving to a safe place in an emergency. Notice: Using coolant other than DEX-COOL® may cause premature engine, heater core, or radiator corrosion. In addition, the engine coolant could require changing sooner, at 30,000 miles (50 000 km) or 24 months, whichever occurs first. Any repairs would not be covered by your warranty. Always use DEX-COOL® (silicate-free) coolant in your vehicle. {CAUTION: Heater and radiator hoses, and other engine parts, can be very hot. Do not touch them. If you do, you can be burned. Do not run the engine if there is a leak. If you run the engine, it could lose all coolant. That could cause an engine fire, and you could be burned. Get any leak fixed before you drive the vehicle. 331