Thermostat, Genuine BMW - F06/F13 640i, F02 740i
Genuine BMW thermostat. Replaces BMW part #11538671514.
This is a direct replacement thermostat for the N55 engine in the F06/F12/F13 640i and F01/F02 740i/740Li (N55 engine). 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 a Genuine BMW N55 thermostat with a two year warranty. Buying a Genuine part will usually be more expensive than an OEM or aftermarket brand but you are assured that it meets BMW's designs for fitment, performance, and longevity. It will also be the very latest design, incorporating any updates or revisions that an aftermarket brand typically will ignore.
Supersedes BMW Part # 11537605431 (11-53-7-605-431)
F12 / F13 (12-18) > 640i
F01 / F02 (2009+) > 740Li
F01 / F02 (2009+) > 740i