Genuine BMW Engine Coolant Expansion Tank Reservoir

The Genuine BMW Engine Coolant Expansion Tank Reservoir (also called a coolant overflow tank, coolant reservoir or radiator expansion tank) is an original equipment cooling system component. It holds the engine coolant that expands as the engine heats up. It also keeps the right coolant level in the system and gives the coolant room to expand and contract during normal operation.

Key Features:

• Original equipment design from BMW, built to the manufacturer's standards for fit and function
• Holds excess coolant as it expands with heat and returns it to the system as the engine cools
• Helps keep the cooling system at the correct pressure and coolant level
• Molded from durable, heat-resistant and coolant-resistant material for long service life
• Includes the factory-style filler neck and connection points so it integrates with the cooling system

A cracked, leaking or discolored expansion tank can cause coolant loss, low coolant warnings and overheating. Replacing it with a genuine BMW part restores proper cooling system operation and helps protect the engine. Select the correct part number for your application from the available options.