How to Flush the Radiator in a Chevy Avalanche

The radiator is the heart of the coolant system for an automobile. If the radiator does not work correctly, the engine can overheat and cause it to fail. To keep the radiator in a Chevy Avalanche healthy, you must perform routine maintenance such as flushing the radiator. You don't need to have an in-depth knowledge of mechanics to do this task, just follow a few easy steps.

Things You'll Need

  • Mineral water
  • Coolant
  • Drain bucket
  • Sealable container
  • Park the Chevy Avalanche on a level surface and set the parking brake. Be sure that the underneath of the car is easily accessible.

  • Open the hood and verify the outer temperature of the radiator. If it's not cool to the touch, wait until the temperature drops before you proceed.

  • Turn the radiator cap one full turn, pause for a few seconds to relieve any internal pressure and then remove the cap entirely.

  • Place a 2-gallon bucket or tray underneath the radiator and directly below the drain plug or petcock valve.

  • Loosen the drain plug to begin removing the old coolant. The drain plug on the Chevy Avalanche doesn't require any tools for removal. It should be on the back of the radiator a couple of inches from the radiator nipple.

  • Dispose of the old coolant in a sealable container, once you fully drain your radiator. Be sure to take the old coolant to a liquid water disposal site or your local auto repair shop, as this liquid is very toxic to pets and people.

  • Close the drain plug, fill the radiator with distilled water and then reopen the drain to flush the water. Repeat this process until the water runs debris-free into the drain container. You can use ordinary tap water, but it can leave sediment deposits behind, which can damage the radiator.

  • Make sure to tighten the drain plug on the radiator. Then, pour fresh coolant into the radiator until it is within an inch of overflowing from the top. You will need roughly 5 gallons of coolant to fill the radiator of a Chevy Avalanche.

  • Start the Chevy Avalanche's engine and allow it to run until the cooling fan turns on twice. Then, shut the engine off and check the coolant level. If it is lower than before, pour more coolant into the radiator. Put the cap on the freshly flushed radiator and close the hood.