Genuine BMW Coolant Expansion Tank Cap

The Genuine BMW Coolant Expansion Tank Cap (also called a coolant reservoir cap or radiator expansion tank cap) is an original equipment part. It seals the cooling system's expansion tank and keeps system pressure at the level BMW specifies.

Key Features:

• Original BMW equipment, built to the manufacturer's standards for fit and function
• Holds cooling system pressure and releases excess pressure through a built-in valve
• Seals the expansion tank to help prevent coolant loss and leaks
• Helps the engine keep a stable operating temperature and helps protect against overheating
• Designed to work with BMW coolant expansion tanks

A worn or faulty cap can cause coolant loss, pressure problems, or overheating. Replacing it with a genuine BMW cap is a simple way to keep the cooling system working as designed. Let the engine cool completely before opening the cap.