GM Service Manual Online
For 1990-2009 cars only

When you decide it is safe to lift the hood, here is what you will see:

3800 V6 Supercharged Engine shown, 3800 V6 Engine similar


Object Number: 1198036  Size: B3
  1. Coolant Recovery Tank

  2. Electric Engine Cooling Fan(s)

  3. Pressure Cap

5.3L V8 Engine


Object Number: 1548402  Size: B3
  1. Pressure Cap

  2. Electric Engine Cooling Fans

  3. Coolant Recovery Tank

Caution: An electric engine cooling fan under the hood can start up even when the engine is not running and can cause injury. Keep hands, clothing, and tools away from any underhood electric fan.

If the coolant inside the coolant recovery tank is boiling, do not do anything else until it cools down. The vehicle should be parked on a level surface.

The coolant recovery tank is located in the rear of the engine compartment on the passenger's side of the vehicle on the 3800 V6 engines. The coolant recovery tank on the 5.3L V8 engine is located in the rear of the engine compartment on the driver's side of the vehicle, behind the engine air cleaner/filter.

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.

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.

If there seems to be no leak, with the engine on, check to see if the electric engine cooling fan(s) are running. If the engine is overheating, the fan(s) should be running. If the fan(s) are not running, the vehicle needs service.

Notice: Engine damage from running your engine without coolant is not covered by your warranty. See Overheated Engine Protection Operating Mode for information on driving to a safe place in an emergency.

Notice: Using coolant other than DEX-COOL® can 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 the vehicle warranty. Always use DEX-COOL® (silicate-free) coolant in the vehicle.

How to Add Coolant to the Coolant Recovery Tank

Caution: Adding only plain water to the cooling system can be dangerous. Plain water, or some other liquid such as alcohol, can boil before the proper coolant mixture will. The vehicle's coolant warning system is set for the proper coolant mixture. With plain water or the wrong mixture, the engine could get too hot but you would not get the overheat warning. The engine could catch fire and you or others could be burned. Use a 50/50 mixture of clean, drinkable water and DEX-COOL® coolant.

If you have not found a problem yet, but the coolant level is not at the cold fill line, add a 50/50 mixture of clean, drinkable water and DEX-COOL® engine coolant at the coolant recovery tank. See Engine Coolant for more information.

Notice: In cold weather, water can freeze and crack the engine, radiator, heater core and other parts. Use the recommended coolant and the proper coolant mixture.

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 the coolant level in the coolant recovery tank is at the cold fill line, start the vehicle.

If the overheat warning continues, there is one more thing you can try. You can add the proper coolant mixture directly to the radiator, but be sure the system is cool before you do it.

Caution: Steam and scalding liquids from a hot cooling system can blow out and burn you badly. They are under pressure, and if you turn the pressure cap -- even a little -- they can come out at high speed. Never turn the cap when the cooling system, including the pressure cap, is hot. Wait for the cooling system and pressure cap to cool if you ever have to turn the pressure cap.

How to Add Coolant to the Radiator (3800 V6 Engines)

Notice: Your engine has a specific radiator fill procedure. Failure to follow this procedure could cause your engine to overheat and be severely damaged.

    3800 V6 Supercharged Engine shown, 3800 V6 Engine similar


    Object Number: 1334877  Size: B3
  1. You can remove the pressure cap when the cooling system, including the pressure cap and upper radiator hose, is no longer hot. Turn the cap slowly counterclockwise.
  2. If you hear a hiss, wait for that to stop. A hiss means there is still some pressure left.

  3. Then keep turning the pressure cap and remove it.
  4. 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.

  5. Remove the Series  III V6 engine cover shield to access the bleed valve.
  6. 3.1. Clean the area around the engine oil fill tube and cap before removing. Twist the oil fill tube, with cap attached, counterclockwise and remove it.

    3800 V6 Engine


    Object Number: 894188  Size: B3

    3800 V6 Supercharged Engine


    Object Number: 1198038  Size: B3
    3.2. Lift the engine cover shield at the front, slide the catch tab out of the engine bracket and remove the cover shield.
    3.3. Put the oil fill tube, with cap attached, in the valve cover oil fill hole until you are ready to replace the cover shield.

    Thermostat Housing


    Object Number: 871908  Size: A2

    After the engine cools, open the coolant air bleed valve located on the thermostat housing near the heater hose.

    3800 V6 Supercharged Engine shown, 3800 V6 Engine similar


    Object Number: 871906  Size: B3
  7. Fill the radiator with the proper DEX-COOL® coolant mixture, up to the base of the filler neck. See Engine Coolant for more information about the proper coolant mixture.
  8. If you see a stream of coolant coming from the air bleed valve, close the valve. Otherwise, close the valve after the radiator is filled.

  9. Rinse or wipe any spilled coolant from the engine and the compartment.
  10. Replace the 3800 Series III V6 engine cover shield.
  11. 7.1. Remove the oil fill tube, with cap attached, from the valve cover.
    7.2. Insert the catch tab on the cover shield under the bracket on the engine.
    7.3. Place the hole in the cover shield over the hole in the valve cover. Install oil fill tube and cap by twisting clockwise.
  12. Then fill the coolant recovery tank to the cold fill line.
  13. Put the cap back on the coolant recovery tank, but leave the pressure cap off.
  14. 3800 V6 Supercharged Engine shown, 3800 V6 Engine similar


    Object Number: 871911  Size: B3
  15. Start the engine and let it run until you can feel the upper radiator hose getting hot. Watch out for the engine cooling fan(s).
  16. By this time, the coolant level inside the radiator filler neck may be lower. If the level is lower, add more of the proper DEX-COOL® coolant mixture through the filler neck until the level reaches the base of the filler neck.
  17. Then replace the pressure cap. At any time during this procedure if coolant begins to flow out of the filler neck, reinstall the pressure cap. Be sure the pressure cap is hand-tight and fully seated.
  18. Check the coolant in the recovery tank. The level in the coolant recovery tank should be at the cold fill line when the engine is cold.

How to Add Coolant to the Cooling System (5.3L V8 Engine)

Notice: The engine has a specific cooling system drain and fill procedure. Failure to follow this procedure could cause the engine to overheat and be severely damaged. If the engine's cooling system needs to be drained and re-filled, please see the dealer/retailer.


Object Number: 809006  Size: A2

You can remove the pressure cap when the cooling system, including the pressure cap and upper radiator hose is no longer hot. Turn the pressure cap slowly counterclockwise.

  1. If you hear a hiss, wait for that to stop. A hiss means that there is still some pressure left.
  2. Then keep turning the pressure cap to remove the pressure cap.
  3. 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.

  4. Fill the cooling system with the proper DEX-COOL® coolant mixture, up to the base of the filler neck. See Engine Coolant for more information about the proper coolant mixture.
  5. Rinse or wipe any spilled coolant from the engine and the compartment.
  6. Then fill the coolant recovery tank to the cold fill line.
  7. Install the coolant recovery tank cap and the pressure cap.
  8. If the coolant in the recovery tank is constantly low, you should have a dealership service department inspect your vehicle for leaks.