GM Service Manual Online
For 1990-2009 cars only

Draining Procedure

Caution: With a pressurized cooling system, the coolant temperature in the radiator can be considerably higher than the boiling point of the solution at atmospheric pressure. Removal of the surge tank cap, while the cooling system is hot and under high pressure, causes the solution to boil instantaneously with explosive force. This will cause the solution to spew out over the engine, the fenders, and the person removing the cap. Serious bodily injury may result.

  1. Park the vehicle on a level surface.
  2. Remove the coolant pressure cap.
  3. Raise and support the vehicle. Refer to Lifting and Jacking the Vehicle in General Information.
  4. Place a drain pan under the drain cock.
  5. Open the radiator drain cock.
  6. Drain the cooling system.
  7. If a complete engine block drain is required, remove the engine block drain plug.
  8. Inspect the coolant.
  9. Follow the appropriate procedure based on the condition of the coolant.
  10. • Normal in appearance -- follow the filling procedure.
    • Discolored -- follow the flush procedure. Refer to Flushing .

Filling Procedure

Tools Required

J 23688 Coolant and Battery Fluid Tester

    Notice: Use the correct fastener in the correct location. Replacement fasteners must be the correct part number for that application. Fasteners requiring replacement or fasteners requiring the use of thread locking compound or sealant are identified in the service procedure. Do not use paints, lubricants, or corrosion inhibitors on fasteners or fastener joint surfaces unless specified. These coatings affect fastener torque and joint clamping force and may damage the fastener. Use the correct tightening sequence and specifications when installing fasteners in order to avoid damage to parts and systems.

  1. Close the radiator drain cock.
  2. Tighten
    Tighten the radiator drain cock to 2 N·m (18 lb in).

  3. If the engine block drain plug was removed, perform the following:
  4. • Apply pipe sealer to the drain plug.
    • Install the drain plug.

    Tighten
    Tighten the drain plug to 22 N·m (16 lb ft).

  5. Lower the vehicle.
  6. Open the cooling system bleeder screws.
  7. Important: Use a 50/50 mixture of DEX-COOL antifreeze and deionized water.

  8. Slowly fill the cooling system with a 50/50 coolant mixture.
  9. Close the cooling system bleeder screws.
  10. Install the coolant pressure cap.
  11. Start the engine.
  12. Run the engine at 2,000-2,500 RPM until the engine reaches normal operating temperature.
  13. Allow the engine to idle for 3 minutes.
  14. Shut the engine off.
  15. Allow the engine to cool.
  16. Top off the coolant as necessary.
  17. Inspect the concentration of the engine coolant using the J 23688 .
  18. Rinse away any excess coolant from the engine and the engine compartment.
  19. Inspect the cooling system for leaks.