Auto Service

1. Open the engine hood of the Audi A4 by pulling the hood-release lever located underneath the steering panel of the car on the driver side. Push the hood up all the way until it locks into place.
2. Locate the coolant tank on the driver-side of the vehicle, just in front of the wheel well. The tank is clear and has a blue screw top. Place a drain pan below the coolant tank underneath the car. This pan will catch the coolant that falls from the tank when its being removed.
3. Remove the three bolts surrounding the coolant tank with the 10 mm socket wrench.
4. Detach the three hoses that run from the radiator to the coolant tank with a clamp removal tool. Wait for the coolant to drain completely into the pan below.
5. Lift the tank out of the engine cavity. Replace it with the new tank. Reattach the hoses with the clamps and fasten the tank with the bolts. Remove the cap and pour in coolant until it reaches the MAX line. Close the hood.

1. Drive your BMW onto a set of ramps and secure the parking brake.
2. Allow sufficient time for the BMW to cool down before beginning. Releasing pressure on a hot coolant system can cause severe burns to your skin from coolant vapor.
3. Open the radiator cap to release pressure on the coolant system.
4. Place a drainage pan under the petcock on the bottom of the radiator. Open the petcock with pliers and drain the contents of the radiator into the drain pan. With older vehicles, the petcock often corrodes. Breaking the petcock when trying to open it is an issue; to help avoid this issue, place a container large enough to catch all the fluid (approximately 4 gallons), remove the lower radiator hose and drain the fluid from there. Reconnect the petcock or place the hose back onto the radiator once drained.
5. Disconnect the cross over tube from the overflow tank and drain the fluid from the overflow tank into the drainage pan.
6. Fill the radiator with 4 gallons of distilled water, close the cap and run the engine until the radiator fan turns on. Allow the engine to cool off, then drain the fluid again. Repeat this process again or until the fluid that drains from the radiator is relatively clear.
7. Place 2 gallons of antifreeze into the radiator and 2 gallons of distilled water in the radiator. Run the engine with the cap off for a period of 5 minutes to expel air from the coolant system. Turn off the engine and top off the radiator with antifreeze. Place the cap back onto the radiator.