Draining Procedure

Caution: As long as there is pressure in the cooling system, the temperature can be considerably higher than the boiling temperature of the solution in the radiator without causing the solution to boil. Removal of the pressure cap while the engine is hot and pressure is high will cause the solution to boil instantaneously- possibly with explosive force-spewing the solution over the engine, fenders and the person removing the cap.

Notice: When adding coolant, it is important that you use GM Goodwrench DEX-COOL or HAVOLINE DEX-COOL coolant. If Coolant other than DEX-COOL or HAVOLINE DEX-COOL is added to the system the engine coolant will require change sooner-at 50 000 km (30,000 mi) or 24 months.

1. Allow the engine to cool completely.
2. Place a drain pan under the radiator drain cock.
3. Install a tube on the radiator drain. Place the end of the tube in the drain pan.
4. Remove the radiator cap.
5. Completely open the radiator drain cock.
6. Allow the coolant to drain from the system until the flow stops.
7. Place a drain pan under the block drain hole plug.
8. Remove the drain hole plug from the engine block.
9. Allow the coolant to drain from the block until the flow stops. There may be more drainage from the radiator at this time.
10. Install the block drain hole plug.
11. Close the radiator drain cock.