Caution: To help avoid the danger of being burned, do not remove the radiator cap while the engine and the radiator are still hot. Scalding fluid and steam can be blown out under pressure if the cap is taken off too soon. Remove the radiator cap before draining the coolant so the coolant is not forced out under pressure.

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 radiator cap while the engine is hot and the pressure is high will cause the solution to boil instantaneously and possibly with explosive force, spewing the solution over the engine, fenders, and person removing the cap. Under some conditions, the engine coolant is combustible.

1. Drain the coolant from the radiator.



2. Remove the drain cock from the threaded hole in the radiator side tank.

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

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. Install the drain cock into the threaded hole in the radiator side tank.

Tighten
Tighten the drain cock to 18 N·m (13 lb ft).

2. Add the proper coolant as specified. Refer to Engine Cooling System Specifications .
3. Start the engine. Inspect for leaks.