Hi, Your drain plug is a push and twist type. It does not come out. I am sending instructions from GM and a second picture with info on the plug. Thanks, Bob
J 26568 Coolant and Battery Tester
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.
Notice: The procedure below must be followed. Improper coolant level could result in a low or high coolant level condition, causing engine damage.
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.
Tighten Tighten radiator drain cock to 2 N·m (18 lb in).
Tighten Tighten the water pump drain plug to 22 N·m (16 lb ft).
Important: It is necessary to maintain the coolant level at the top of the surge tank label to insure all the air has been purged from the cooling system.