DEX-COOL antifreeze is a GM-formulated antifreeze. As with all coolants, DEX-COOL must be periodically replaced. Replacement of DEX-COOL in a GM vehicle is a simple process that will require a bucket and simple hand tools. Replacing your coolant will help ensure optimum cooling system operation and help to provide anti-corrosion protection.
Park your car and make sure the engine has cooled down and is cold to the touch. For most GM models you will have enough access without lifting the front end of your car.
Remove the radiator cap (located on the top of the radiator, which is located at the front of the engine). Set the cap aside. Position a drain pan below your car and use a pair of pliers to open the petcock on the radiator, catching the coolant in your drain pan. Allow the coolant to fully drain before closing the petcock.
Fill the radiator with distilled water, then run the engine with your heater turned on high. You can also run distilled water through to catch any old dirty coolant that may still be in the system. (Note: You must use distilled water, as it is mineral free. Do not use tap water.) Coolant flows through the heater core, so turning the heat on high will make sure the distilled water runs through the entire system. Shut down the car after a few minutes and drain the water from the radiator lower petcock.
Refill your radiator with fresh DEX-COOL. Check your owner's manual to confirm your specific vehicle's coolant volume requirements. Check the instructions on your DEX-COOL to see if it is to be mixed with distilled water, and blend accordingly. You can purchase premixed DEX-COOL.
