BMW Cooling System Parts & Accessories for BMW E90 M3 S65 4.0L

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The cooling system is arguably the weakest point in numerous BMWs. If you drive an aging BMW or plan on taking your car to the track like we do, we recommend beefing up your cooling system before going to the track. Generally, the main components in your cooling system that are prone to failure include the following: expansion tank, factory hoses, water pump, thermostat, fan (especially if your vehicle comes factory with a clutch fan), and radiator. Factory BMW expansion tanks are plastic and prone to either breaking off at connection points or combusting. As factory rubber hoses age they either crack or break over time - we offer silicone cooling hose upgrades for most applications to avoid future failures. If you have an older vehicle, your water pump likely comes from the factory with a plastic impeller - we offer upgraded water pumps with metal impellers that are far more reliable. Newer model BMWs utilize electric water pumps - BMW spent millions of dollars engineering these water pumps, but they fail so often that we recommend replacing at 60,000 mile service intervals to avoid being stranded on the side of the road. In terms of thermostats, we offer various upgraded thermostats for racing applications. If your BMW utilizes a clutch fan from the factory, we have several options available in terms of universal electric fans - we recommend replacing these to avoid sending brittle plastic fan blades through your hood. For radiators, we recommend swapping out your radiator for one that does not use plastic connection points like your factory radiator.

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Burger Motorsports - Corporate Logo
T#:38621407
Part#: BMS-TCBS
Back Ordered
$ 25.00 USD
Free Shipping on orders $49 and up
Replace your fragile OEM plastic coolant bleeder screw, which is prone to cracking and failure, with a premium titanium upgrade built for strength and style under the hood. Factory plastic components weaken over time due to constant heat cycles, leading to brittleness and potential failure. Our titanium replacement delivers superior durability, being twice as strong as aluminum yet 45% lighter than steel, ensuring unmatched resilience and long-term reliability for your coolant system. More than an upgrade, it’s a must-have for engine longevity. CNC-machined from solid titanium, each screw features a laser-etched Burger Motorsports logo and is hand-burned to create unique color patterns—no two are alike. A heavy-duty replacement O-ring is included for a perfect fit.
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Race German - Corporate Logo
T#:6827887
Part#: RGCTSAM12
In Stock
$ 35.99 USD
Free Shipping on orders $49 and up
Race German has devoted themselves to providing quality products for late model BMWs that cover both street and track applications. Race German has now grown their catalog to a wide variety of models and products geared towards keeping your car looking and running nice. For those looking to install an aftermarket coolant temp gauge, Race German has the perfect accessory for you! This adapter is machined out of aluminum and splices into your upper radiator hose. Perfect for use with Race German's E30 temperature gauge but has compatibility with a wire variety of other cars as well! Features: Tapped for M12x1.5 sized sensor 38mm diameter outlets which fit most BMW hoses Includes 2x hose clamps **Does not include temp sensor
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Race German - Corporate Logo
T#:6827888
Part#: RGCTSA1/8NPT
In Stock
$ 35.99

This product was last offered at the strikethrough price on
10-07-2026

$ 31.99 USD
Limited Qty Sale
Free Shipping on orders $49 and up
$ 35.99

This product was last offered at the strikethrough price on
10-07-2026

$ 31.99 USD
Limited Qty Sale
Free Shipping on orders $49 and up
Race German has devoted themselves to providing quality products for late model BMWs that cover both street and track applications. Race German has now grown their catalog to a wide variety of models and products geared towards keeping your car looking and running nice. For those looking to install an aftermarket coolant temp gauge, Race German has the perfect accessory for you! This adapter is machined out of aluminum and splices into your upper radiator hose. Perfect for use with Race German's E30 temperature gauge but has compatibility with a wire variety of other cars as well! Features: Tapped for 1/8NPT sized sensor 38mm diameter outlets which fit most BMW hoses Includes 2x hose clamps **Does not include temp sensor
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Redline - Corporate Logo
T#:640437
Part#: 81205
In Stock
$ 68.99 USD
Free Shipping
$ 68.99 USD
Free Shipping
Red Line SuperCool Concentrate fortified with WaterWetter is a concentrated antifreeze/coolant designed to maximize the performance of your cooling system with superior protection against cavitation corrosion/erosion. Using SuperCool Concentrate diluted with distilled water protects the entire cooling system keeping new components like new for 5 years/150,000 miles and prevents further damage to older components. Red Line’s proprietary coolant additive formula enhances the fluid’s ability to transfer heat, reducing operating temperatures by up to 20*F and prolonging the life of the entire cooling system. Red Line's SuperCool is an OAT coolant that is a Nitrate and Silicate Free product with its own proprietary corrosion technology to offer superior protection for aluminum engines found in all European vehicles, performance vehicles, as well as other applications. SuperCool will not void the factory warranty either. It can be used to top off the existing coolant of any BMW and will not cause any ill-effects on the cooling system because it is silicate and nitrate free. It is still better to flush it out and switch completely to SuperCool to get all the full benefits of the product in performance and protection.
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Redline - Corporate Logo
T#:640436
Part#: 81215
In Stock
$ 54.99 USD
Free Shipping on orders $49 and up
Red Line SuperCool Performance Coolant fortified with WaterWetter is a 50/50 prediluted antifreeze/coolant designed to maximize the performance of your cooling system with superior protection against cavitation corrosion/erosion. Using 100% SuperCool Performance protects the entire cooling system, keeping new components like new for 5 years/150,000 miles and prevents further damage to older components. Red Line’s proprietary coolant additive formula enhances the fluid’s ability to transfer heat, reducing operating temperatures by up to 20*F and prolonging the life of the entire cooling system. Red Line's SuperCool is an OAT coolant that is a Nitrate and Silicate Free product with its own proprietary corrosion technology to offer superior protection for aluminum engines found in all European vehicles, performance vehicles, as well as other applications. SuperCool will not void the factory warranty either. It can be used to top off the existing coolant of any BMW and will not cause any ill-effects on the cooling system because it is silicate and nitrate free. It is still better to flush it out and switch completely to SuperCool to get all the full benefits of the product in performance and protection.
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Genuine BMW Motorsport - Corporate Logo
T#:5574
Part#: 11518331044
Special Order: No Guaranteed ETA
$ 999.99 USD
Free Shipping
$ 999.99 USD
Free Shipping
Upgrade from the plastic impeller on the stock water pump to this aluminum impeller pump originally developed by BMW for the M3 GT4. This aluminum water pump was designed to stand up to the abuse of racing but can be used on a standard street car.
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Redline - Corporate Logo
T#:394769
Part#: REDLINE5A
In Stock
Starting at $ 15.99 USD
Free Shipping on orders $49 and up
Starting at $ 15.99 USD
Free Shipping on orders $49 and up
Water Wetter is a unique wetting agent for cooling systems which reduces coolant temperatures by as much as 30*F. This liquid product can be used to provide rust and corrosion protection in plain water for racing engines, which provides much better heat transfer properties than glycol-based antifreeze.
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Redline - Corporate Logo
T#:3607
Part#: 1-WW-12Z
In Stock
$ 15.99 USD
Free Shipping on orders $49 and up
Water Wetter is a unique wetting agent for cooling systems which reduces coolant temperatures by as much as 30*F. This liquid product can be used to provide rust and corrosion protection in plain water for racing engines, which provides much better heat transfer properties than glycol-based antifreeze. Or it can be added to new or used antifreeze to improve the heat transfer of ethylene and propylene glycol systems. Designed for modern aluminum, cast iron, copper, brass, and bronze systems.

We have been using RedLine Oil in our street cars and race cars for years. Hands-down, it is the Number One brand of high performance lubricant for BMWs.
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Moroso - Corporate Logo
T#:29666104
Part#: 63850
In Stock at Vendor
$ 586.00 USD
Free Shipping on orders $49 and up

The coolant expansion tank provides hot coolant with a place to travel, preventing pressure buildup within your cooling system. On many BMWs, this component is constructed from plastic. While cheap to replace and manufacture, a failed cooling tank can cause costly engine damage.

With this issue in mind, Moroso designed a high-quality replacement. Featuring TIG welded, 100% aluminum construction, this tank is sure to outperform it's factory counterpart.

Features:

Key Benefits:

Direct bolt-in replacement for stock, 2 piece plastic tank Fabricated Aluminum for strength, factory tanks fail after repeated high heat situations & age Features billet aluminum mounting tab/bleeder assembly for strength and precision No cutting of factory hoses is required and accepts the factory clip-on hose Included is a Moroso (63324) racing radiator cap that operates in the same pressure range as the factory cap Moroso radiator cap mounts to a billet aluminum neck that will not strip out like plastic threaded necks Can be polished, chromed, or powder coated or left as-is

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