Replace-expansion-tank

From MyE46

Replacing the Coolant Expansion Tank

1. Drain system of coolant by removing radiator drain plug
2. Remove the large silver connector that goes to the transmission from the radiator. It has a clip just like the rest of the coolant hoses. Coolant will come out after you disconnect!
3. Remove the upper radiator hose, it is connected in three spots, the engine, radiator, and expansion tank. If you are having a hard time getting it loose, use a screwdriver and rubber mallet to tap it out gently.