Description:

Xspeedonline Radiator Expansion Tank Cap, Coolant Reservoir Cap Cover 17117639020, 17117521071 for BMW 335i GT xDrive 2014-2016, 335i xDrive 2009-2015, 335is 2011-2013, 335xi 2007-2008 - 1.4bar.
Replaces Part Numbers: 17117639020, 17117521071/ 17117639021, 17137516004.
Critical Pressure Regulation Function: Serves as a pressure-regulating valve, maintaining proper cooling system pressure to prevent overheating and coolant issues..
Common Cooling Problem Solution: Addresses symptoms including coolant leaks, engine overheating, abnormal system pressure, and physical cap deterioration in vehicles..
Simple Direct Replacement: Engineered as a direct fit replacement requiring no modifications; simply remove the old cap and install the new unit to restore proper cooling system function..