2004 Chevrolet Avalanche Owner's Manual - Page 381

Adding Coolant If you need more coolant, add the proper DEX-COOL coolant mixture at the surge tank, but only when the engine is cool. ® Engine Overheating You will find a coolant temperature gage on your vehicle's instrument panel. See Engine Coolant Temperature Gage on page 3-41. In addition, you will find an ENGINE COOLANT HOT, ENGINE OVERHEATED and a REDUCED ENGINE POWER message in the DIC on the instrument panel. See DIC Warnings and Messages on page 3-60. {CAUTION: You can be burned if you spill coolant on hot engine parts. Coolant contains ethylene glycol, and it will burn if the engine parts are hot enough. Do not spill coolant on a hot engine. When replacing the pressure cap, make sure it is hand-tight. Overheated Engine Protection Operating Mode If an overheated engine condition exists and the REDUCED ENGINE POWER message is displayed, an overheat protection mode which alternates firing groups of cylinders helps prevent engine damage. In this mode, you will notice a loss in power and engine performance. This operating mode allows your vehicle to be driven to a safe place in an emergency. Driving extended miles (km) and/or towing a trailer in the overheat protection mode should be avoided. Notice: After driving in the overheated engine protection operating mode, to avoid engine damage, allow the engine to cool before attempting any repair. The engine oil will be severely degraded. Repair the cause of coolant loss, change the oil and reset the oil life system. See Engine Oil on page 5-16. Coolant Surge Tank Pressure Cap The coolant surge tank pressure cap must be fully installed on the coolant surge tank. See Engine Compartment Overview on page 5-12 for more information on location. Notice: If the pressure cap is not tightly installed, coolant loss and possible engine damage may occur. Be sure the cap is properly and tightly secured. 5-29