BMW Cooling System Parts & Accessories for BMW X5 M S63 4.4L

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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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Red Line Supercool Performance Coolant - Concentrate - 1 Gallon ...
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Redline - Corporate Logo
T#:640437
Part#: 81205
In Stock
$ 68.99 USD
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$ 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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Bav Auto Coolant Expansion Tank - With Level Sensor - E70 X5, E71 X6 ...
affirm Starting At 0% APR - Subject To Eligibility. See Lending Terms
Bavarian Autosport - Corporate Logo
T#:638093
Part#: 17138621092
In Stock
Sale - Save 20% $ 60.99

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

$ 48.79 USD
Free Shipping on orders $49 and up
Sale - Save 20%
$ 60.99

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

$ 48.79 USD
Free Shipping on orders $49 and up
Replace your old expansion tank to prevent potential failure or leaks. Includes a brand new coolant level sensor.
Red Line SuperCool Performance Coolant - Pre-Mixed - 1 Gallon ...
affirm Starting At 0% APR - Subject To Eligibility. See Lending Terms
Redline - Corporate Logo
T#:640436
Part#: 81215
Ships on Aug 17, 2026
$ 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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Red Line Water Wetter Heat Transfer Agent
affirm Starting At 0% APR - Subject To Eligibility. See Lending Terms
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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Red Line Water Wetter Coolant Additive
affirm Starting At 0% APR - Subject To Eligibility. See Lending Terms
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.
Show More Show Less
Bav Auto Temperature Sensor - BMW E39 E46 E9X E60 F01/02
affirm Starting At 0% APR - Subject To Eligibility. See Lending Terms
Bavarian Autosport - Corporate Logo
T#:639833
Part#: 13621433076
In Stock
Sale - Save 20% $ 14.99

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

$ 11.99 USD
Free Shipping on orders $49 and up
Sale - Save 20%
$ 14.99

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

$ 11.99 USD
Free Shipping on orders $49 and up
This is the coolant temperature sensor used in many BMW models from the late-1990s to the mid-2010s. The engine computer relies on the coolant temp to set the fuel mapping for the engine. As the car warms up the computer changes the fuel mixture. If your car is running a bit rich (too much fuel) it could be because this sensor is failing and not sending the correct info to the computer. This sensor is located in a variety of places depending on the engine. But it's one of those easy replacement items 'while you're in there' when doing a water pump or thermostat replacement. From 1974 to 2019, Bavarian Autosport was one of the premier vendors for BMW and MINI auto parts. We are happy to preserve the Bav Auto legacy by continuing to carry their high-quality products into the future. All Bav Auto parts will remain unchanged in design and sourced from the same OEM suppliers to ensure long-lasting reliability. We trust these parts, accessories, and upgrades so confidently that we back every Bavarian Autosport branded component with a 2-year warranty.
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