Select Vehicle
BMW
Mini
Create an account to be able to build Wish Lists.
Please ensure your correct model is selected
This product was last offered at the strikethrough price on
06-14-2026
This product was last offered at the strikethrough price on
06-14-2026
Replace the Achilles heel of your factory cooling system with a stout and reliable mechanical thermostat setup.
The factory E46 thermostat housing is a combined unit featuring a plastic housing and a built in thermostat that you cannot replace separately. These plastic all-in-one units are commonly know to crack or fail causing a headache, a trip on the tow truck and possible damage to your engine.
Taking cues from the reliable M50 thermostat setup we designed a an assembly that not only converts your plastic housing into a billet aluminum unit but also swaps out the integrated thermostat for a separate replaceable thermostat. The ability to swap out thermostats separately from the whole housing opens up doors to changing thermostats to different temperature ratings based on your application while also providing lower maintenance costs. No longer do you have to replace the whole housing but just the thermostat itself.
The billet housing is designed to be utilized with E46 M3 upper and lower radiator hoses and also features -16 ORB connections for custom radiator hoses. A major upgrade from the factory and aftermarket plastic units. Our thermostat housing kit can be used by the savvy daily driver or the track hero who wants to ensure the durability of their cooling system.
Key benefits:
Uses M50/S50 mechanical thermostat for increased reliability
Option to use aftermarket colder thermostats if desired
Thermostat can be replaced separately for lower maintenance cost
Barbed hose connections for use with E46 M3 hoses or built in -16 ORB connections for custom radiator hoses
Design:
Machined out of a single piece of billet 6061 aluminum, this thermostat housing will withstand higher prolonged temperatures and abuse for performance applications
Black anodized with engraved Turner logo on the front to match the Turner Motorsports Power Steering Reservoir
Viton gasket for superior sealing performance
For use with E46 M3 radiator hoses 11537830715 and 11537830716
Kit contents:
6061 Billet Aluminum Thermostat Housing
Mechanical Thermostat
Thermostat Housing Gasket
Thermostat Harness
Optional Silicone or Rubber E46 M3 coolant hoses
Product Development:
Our Billet Thermostat Housing upgrade was designed, engineered, tested and quality inspected by our Research and Development team at Turner. Nothing but the highest level of precision and quality through leading-edge product development technology including FARO laser scanning for reverse engineering and quality inspection, SolidWorks 3D CAD modeling, rapid prototyping utilizing our in-house 3D printer and rigorous long term product testing.
This product was last offered at the strikethrough price on
05-03-2026
This product was last offered at the strikethrough price on
05-03-2026
The thermostat regulates the temperature of your coolant. At a predetermined temperature the thermostat will open to let coolant flow to the radiator and be cooled by airflow or the fan. Over time the thermostat will become stuck open or closed, leading to a variety of issues. A closed thermostat will never allow the coolant to reach the radiator and be cooled. Hot coolant will continue to circulate through the engine and absorb even more heat until boiling and the system overheats. An open thermostat is not as bad but is still not ideal - the coolant is always cool, with the temp needle always reading in the cool range. This tells the ECU to richen the fuel mixture to bring the car up to normal operating temp. So your fuel mileage decreases and the car runs rich.
Replacing the thermostat is an easy but messy job. This thermostat includes the main o-ring (but a housing gasket may be required). Consider replacing the housing and any associated temp sensors while you're in there. The cooling system will need to be bled after.
Most of the engines from the mid-1980s through the 1990s use the same thermostat design and they are interchangeable among the different temperatures. This is the 68*C thermostat, at the bottom of the temperature range. It should only be used in racing situations such as when deleting the engine fan. However, keep in mind that BMW spent a lot of time engineering the cooling system to work in all kinds of conditions and changing thermostat temperature is not recommended to fix any failures in the cooling system.
Mishimoto makes coolant tanks, radiators and much more for your Mini/BMW. Established in 2003 their commitment to absolute quality in the aftermarket world is evident through the quality and performance enhancing products they offer.
This thermostat fits the following BMWs:
1977-1983 E21 BMW 323i
1986-1991 E30 BMW 318is 318ic 325e 325es 325i 325ic 325is 325ix
1992-1999 E36 BMW 318i 318is 318ti 318ic 323is 323ic 325i 325is 325ic 328i 328is 328ic M3
1982-1988 E28 BMW 528e
1986-1988 E28 BMW 535i
1989-1995 E34 BMW 525i 535i
1997-1998 E39 BMW 528i
1986-1989 E24 BMW 635csi
1988-1994 E32 BMW 735i 735il
1997-2000 Z3 BMW Z3 2.8 M Roadster M Coupe
BMW E46 M54 AAF Low Temp Thermostat Kit - Partial is an essential upgrade for enthusiasts looking to optimize engine performance and reliability. Developed by Advanced Auto Fabrication (AAF), this kit addresses the limitations of the factory M54 thermostat, which maintains a temperature range of 80-103°C and opens the mechanical failsafe at 110°C. For race conditions where maintaining a lower temperature is crucial, this kit replaces the stock electronic thermostat with a manual unit, allowing the engine to run at a safer and more efficient temperature. This upgrade not only enhances engine longevity but also reduces stress from high-temperature operation, minimizes heat soak, and increases power.
Partial Kit Contents:
