Genuine BMW 17-13-8-665-638 Coolant Expansion Tank Cap

The Genuine BMW 17-13-8-665-638 expansion tank cap is an OEM replacement coolant reservoir cap designed specifically for 2019-2025 BMW vehicles equipped with 2.0L and 3.0L engines. This screw-on pressure cap maintains the proper seal and pressure within the cooling system to prevent overheating and coolant loss.

Key Features:

• Genuine BMW OEM part ensuring perfect fit and quality
• Constructed from durable automotive-grade plastic with crack and corrosion resistance
• Maintains proper cooling system pressure for optimal engine performance
• Direct replacement for worn or damaged expansion tank caps
• Designed for G-chassis BMW models including G20 3 Series, G22 4 Series, G42 2 Series, and G29 Z4

This expansion tank cap is a critical component of your BMW's cooling system, helping coolant flow properly during thermal expansion and contraction. Compatible with numerous BMW models including 230i, 330e, 330i, 430i, 530i, 540i, 740i, 750e, M2, M240i, M340i, M440i, X4, and Z4 from 2019-2025 model years. Backed by BMW's factory warranty for reliable long-term performance.