Thermostat, Behr - 228i/328i/428i/528i, X1/X3/X4 28i, Z4 28i

This is a direct replacement thermostat for the N20/N26 engine in the F22 228i, F30 328i, F32 428i, F10 528i, X1/X3/X4 28i, and Z4 28i (including xDrive models). Your engine's thermostat regulates coolant flow and temperature in the cooling system. When open it allows hot coolant to flow into the radiator to be cooled. When closed the coolant circulates through the engine, where it stays warm. A failed thermostat will either be open or closed with the engine running too cold (poor fuel economy and performance) or too hot (overheating). It can also impact your cabin heating/cooling since that system is drawn from your heater core. On the modern cars like above the car's electronics control the thermostat to regulate various temperature systems in the car.

This is an OEM N20 thermostat manufactured by Mahle-Behr - the original supplier to BMW for this part, as well as many other cooling parts. As the OEM it meets all of BMW's original design, fitment, and performance requirements and is TUV approved. OEM parts are the best alternative to more expensive Original BMW parts because they are virtually identical without the inflated price tag. This part has a two year warranty.

Supersedes the following BMW part numbers:
11538648791 (11-53-8-648-791)
11538636594 (11-53-8-636-594)
11538636595 (11-53-8-636-595)
11537633476 (11-53-7-633-476)
11537588257 (11-53-7-588-257)
11537633477 (11-53-7-633-477)

BMW Fitments:

2 Series
F22 / F23 (2014+) > 228i
F22 / F23 (2014+) > 228i xDrive
3 Series
F30 / F31 / F34 (2012-2019) > 320i
F30 / F31 / F34 (2012-2019) > 320i xDrive
F30 / F31 / F34 (2012-2019) > 328i
F30 / F31 / F34 (2012-2019) > 328i xDrive
4 Series
F32 / F33 / F36 (14-20) > 428i
F32 / F33 / F36 (14-20) > 428i xDrive
5 Series
F10 / F11 (11-16) > 528i N20 (2012-2016)
F10 / F11 (11-16) > 528i xDrive N20 (2012-2016)
X1 Series
E84 X1 (2013-2015) > X1 28i
E84 X1 (2013-2015) > X1 28i xDrive
X3 Series
F25 X3 (2011-2017) > X3 sDrive28i
F25 X3 (2011-2017) > X3 xDrive28i
X4 Series
F26 X4 (2015-2018) > X4 28i xDrive
Z Series
E89 Z4 (2009-2016) > Z4 sDrive28i