BMW Thermostats for BMW 3 Series E46 (1999-2005)

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BMW thermostats are known to fail, but luckily they typically fail wide open - meaning that your car can still cool. We offer thermostats from various OE suppliers we trust along with upgraded motorsport specific thermostats where applicable to make sure your BMW stays cool on track.
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Mechanical Thermostat Conversion - M52TU/M54
10X Entries Into Our F80 M3 Sweepstakes
Turner Motorsport - Corporate Logo
T#:20617634
Part#: 008785LA01T
Ships on Dec 9, 2026
Sale - Save 17% $ 376.99

This product was last offered at the strikethrough price on
06-14-2026

Starting at $ 312.37 USD
Free Shipping on orders $49 and up
Sale - Save 17%
$ 376.99

This product was last offered at the strikethrough price on
06-14-2026

Starting at $ 312.37 USD
Free Shipping on orders $49 and up

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.

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Cooling System Refresh Kit - Level 1
10X Entries Into Our F80 M3 Sweepstakes
Packaged by Turner - Corporate Logo
T#:15744012
Part#: 32411712735-KT
In Stock
Sale - Save 5% $ 670.99

This product was last offered at the strikethrough price on
09-09-2026

$ 636.66 USD
Free Shipping on orders $49 and up
Sale - Save 5%
$ 670.99

This product was last offered at the strikethrough price on
09-09-2026

$ 636.66 USD
Free Shipping on orders $49 and up
Stop the problems before they arise. If you vehicle has 60,000 miles or more, replace all of these components to ensure that your vehicle stays healthy. To keep everything in top order, continue to replace these components at 60,000 mile intervals. Water pump failure, cracked plastic housings, and expansion tank leaks will not be a concern once all these problem parts are replaced. Included in this kit are the following parts. Rein Water Pump with metal impeller FAE Fan Switch Vaico Q+ thermostat - made in Germany! New O-ring Sealing Gaskets OEM Expansion Tank & Cap 1 Gallon Coolant Rein Upper & Lower Radiator Hoses
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Bav Auto Thermostat With Aluminum Housing - M52TU M54
10X Entries Into Our F80 M3 Sweepstakes
Bavarian Autosport - Corporate Logo
T#:12544802
Part#: 11531437040
In Stock
Sale - Save 19% $ 104.99

This product was last offered at the strikethrough price on
05-03-2026

$ 84.99 USD
Free Shipping on orders $49 and up
Sale - Save 19%
$ 104.99

This product was last offered at the strikethrough price on
05-03-2026

$ 84.99 USD
Free Shipping on orders $49 and up
The plastic thermostat cover in your BMW is a known point of failure. Throughout years of repeated contact with hot coolant, the plastic can crack and cause massive coolant leaks and potential overheating. Eliminate one of the weak links in your cooling system with a replacement aluminum thermostat housing. By installing this aluminum unit, you have no worries as far as plastic housing cracks go
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Thermostat With Housing
10X Entries Into Our F80 M3 Sweepstakes
Bremmen Parts - Corporate Logo
T#:26494584
Part#: 11537509227
In Stock
Sale - Save 25% $ 60.99

This product was last offered at the strikethrough price on
05-03-2026

$ 45.99 USD
Free Shipping on orders $49 and up
Sale - Save 25%
$ 60.99

This product was last offered at the strikethrough price on
05-03-2026

$ 45.99 USD
Free Shipping on orders $49 and up

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