Replacing your E38 Coolant Expansion Tank

[BimmerMan]

As your E38 is starting to get older, the plastic items in the engine will start to break down. One of the culprits is the expansion tank that lives on the side of the radiator cowl. Replacment often solves the problem of the mystery coolant leak as they tend to crack on the side that is hidden away from view aswell as the area where the level sensor plugs in...

Here is the guide for replacment...
E38 Coolant Expansion Bottle Replacment