Mosselman Oil Thermostat N55 (F-Series)

The N54, N55 and S55 engines are no strangers to oil cooling problems, that’s why we recommend installing the MSL Oil Thermostat, especially for cars that are tuned. The standard oil temperature will reach around 120°C (250°F) with a normal driving style. The MSL Oil Thermostat will open at a lower temperature than the standard oil thermostat (at 85°C / 185°F) and will keep the temperature stable between 95 and 105°C (200 and 220°F), depending on the car model.

Installing the MSL thermostat ensures a cooler oil temperature which will result in more stable performance, but above all this improves the reliability of the engine. It is equipped with a real thermostat, not an always open solution. The oil will still reach the operating temperature at the same time as a stock thermostat.

Installation instructions come with kit.

Suitable for F87 M2 Coupe (N55), F20 M135i Hatch, F22 M235i Coupe, F23 M235i Convertible, F30 335i Sedan, F31 335i Touring, F34 335i Gran Turismo, F32 435i Coupe, F33 435i Convertible and F36 435i Gran Coupe.

Note: You will need the N54 Oil Thermostat for the E-Series 135i and 335i with the N55 engine.

A highly recommended upgrade for N54, N55 and S55 engines.

The Thermostat is plug-and-play and made out of a solid block of high-grade aluminum at Mosselman's own facility. It is equipped with a real thermostat, not an always open solution. The oil will still reach the operating temperature at the same time as a stock thermostat.

Additionally to the thermostat, Mosselman have oil cooler kits for the 1-Series E8x and the 3-Series E9x. We advise the Oil Cooler Kit for cars that use the full performance of the car during track use. The kits are available as single or twin cooler kits. The single cooler kit replaces the OEM cooler on the right side of the car, the twin kit will add an extra cooler on the left side of the car.

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"The N55 engine is no stranger to oil cooling problems, that’s why we recommend installing the MSL Oil Thermostat. The standard oil thermostat will reach around 120 degrees Celsius with a normal driving style. The MSL Oil Thermostat will open at a lower temperature than the standard oil thermostat (at 85 degrees Celsius) and will keep the temperature stable between 95 and 105 degrees Celsius, depending on the car model. Installing the MSL thermostat ensures a cooler oil temperature which will result in more stable performance, but above all this improves the reliability of the engine. It is recommended to install the thermostat, especially for cars that are tuned.

The Thermostat is plug-and-play and made out of a solid block of high-grade aluminum at our own facility. It is equipped with a real thermostat, not an always open solution. The oil will still reach the operating temperature at the same time as a stock thermostat.

Note: The Oil Thermostat Installation kit prevents the Oil Thermostat from leaking and is highly recommended when installing the MSL Oil Thermostat. The kit includes 2 x O-ring for the oil hose and 1x rubber oil filter housing gasket. We advise to add it to your order."

MARK HENDRIKX - AUTOMOTIVE ENGINEER AT MOSSELMAN

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Yes, it is equipped with a real thermostat, not an always open solution. The oil will still reach the operating temperature at the same time as a stock thermostat.

Do I need new gaskets for the installation?

Yes, we highly recommend replacing the gasket and 0-rings to prevent the thermostat from leaking. We have an installation kit available, it includes 2 x O-ring for the oil hose and 1x rubber oil filter housing gasket. We advise to add it to your order.

Installation Time

The thermostat is plug-and-play, which means that you don't have to make modifications to install the thermostat. Just remove the old one and replace it with our MLS Oil Thermostat. The installation time will be approximately 30 minutes.

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