Cooling System Flushing

 WARNING: Always allow the engine to cool before opening the cooling system. Do not unscrew the coolant pressure relief cap when the engine is operating or the cooling system is hot. The cooling system is under pressure; steam and hot liquid can come out forcefully when the cap is loosened slightly. Failure to follow these instructions may result in serious personal injury.

NOTE: To remove rust, sludge and other foreign material from the cooling system, use cooling system flush that is safe for use with aluminum radiators. For additional information, refer to Specifications. This cleaning restores cooling system efficiency and helps prevent overheating. A pulsating or reversed direction of flushing water will loosen sediment more quickly than a steady flow in the normal coolant flow direction. In severe cases where cleaning solvents will not clean the cooling system efficiently, it will be necessary to use the pressure flushing method using cooling system flusher. Dispose of old coolant and flushing water contaminated with antifreeze and cleaning chemicals in accordance with local, state or federal laws.

1. Add Premium Cooling System Flush to the cooling system and follow the directions on the package.

2. Drain the cooling system. For additional information, refer to Cooling System Draining, Filling and Bleeding .

3. Remove the radiator. For additional information, refer to Radiator — 3.5L Ti-VCT or Radiator — 3.5L GTDI .

4. NOTICE: Radiator internal pressure must not exceed 138 kPa (20 psi). Damage to the radiator can result.

   Backflush the radiator with the radiator in an upside-down position with a high-pressure hose in the lower hose location and backflush.

5. Remove the thermostat. For additional information, refer to Thermostat — 3.5L Ti-VCT or Thermostat — 3.5L GTDI .

6. Backflush the engine. Position the high-pressure water hose into the engine through the engine return and backflush the engine.

7. Install the thermostat. For additional information, refer to Thermostat — 3.5L Ti-VCT or Thermostat — 3.5L GTDI .

8. Install the radiator. For additional information, refer to Radiator — 3.5L Ti-VCT or Radiator — 3.5L GTDI .

9. Fill the cooling system. For additional information, refer to Cooling System Draining, Filling and Bleeding .