How to Change Antifreeze on a 2003 Chevrolet 4.8L Engine
- 1). Disconnect the ground cable from the negative battery terminal. Loosen the retaining bolt using a wrench. Then pull the clamp off the terminal
- 2). Unscrew the radiator cap from the radiator. Press down on the cap with your hand and rotate it counterclockwise. Then lift the cap off the radiator.
- 3). Locate the petcock valve on the lower right corner of the radiator. Place a waste oil collection pan underneath it.
- 4). Open the petcock valve by rotating it counterclockwise with a needle nose pliers. Allow the radiator to drain completely.
- 5). Close the petcock by rotating it counterclockwise with a needle nose pliers.
- 1). Fill the radiator with a 50/50 mix of antifreeze and water.
- 2). Reconnect the ground cable to the negative battery terminal. Slide the clamp over the terminal. Then tighten the retaining bolt with a wrench.
- 3). Run the engine with the radiator cap off the radiator for three to five minutes. This will bleed air from the cooling system.
- 4). Add more coolant to the radiator if necessary. You should fill the radiator to just below the radiator cap.
- 5). Screw the radiator cap onto the radiator.
Draining the Antifreeze
Refilling the Antifreeze
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