BMW Cooling System Parts & Accessories for BMW F86 X6 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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AutoTecknic Dry Carbon Charge Cooler Tank Cap Cover - Gloss Finish ...
affirm Starting At 0% APR - Subject To Eligibility. See Lending Terms
AUTOTECKNIC - Corporate Logo
T#:39971051
Part#: BM-0032
In Stock
$ 64.99 USD
Free Shipping on orders $49 and up
A premium dry carbon fiber engine bay upgrade that enhances the performance styling of compatible BMW models with a sleek, UV-resistant finish and easy OEM-style installation.
Silver Auxiliary Coolant Reservoir Cap
affirm Starting At 0% APR - Subject To Eligibility. See Lending Terms
Precision Raceworks - Corporate Logo
T#:38128032
Part#: 201-0394-SIL
Ships in 7 Business Days
$ 99.99

This product was last offered at the strikethrough price on
01-22-2026

$ 94.99 USD
Free Shipping on orders $49 and up
$ 94.99 USD
Free Shipping on orders $49 and up

BMW Silver Auxiliary Coolant Reservoir Cap is the perfect upgrade for BMW owners looking to enhance both the aesthetics and functionality of their engine bay. Unlike generic aftermarket caps that overlook critical pressure regulation, this precision-engineered cap retains the OEM pressure release functionality, ensuring safe and reliable coolant system performance.

Crafted from high-quality billet aluminum, this reservoir cap offers superior durability and resistance to heat and fluids, preventing warping or degradation over time. Unlike adhesive-based cap covers that can loosen or fall off, this cap is a direct replacement for the factory component, providing a secure, high-performance solution.

  • OEM pressure release functionality – Maintains proper system regulation for optimal coolant performance
  • Premium billet aluminum construction – Offers enhanced durability and longevity
  • Direct replacement design – Secure fit without adhesives or modifications
  • Resistant to heat and fluids – Ensures long-lasting reliability in extreme conditions
  • Performance-inspired look – Adds a sleek, high-end appearance to your engine bay
  • Upgraded durability – Prevents cracking, leaks, and premature wear

Upgrade your BMW’s cooling system with the BMW Silver Auxiliary Coolant Reservoir Cap, blending performance, reliability, and premium styling.

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AutoTecknic Dry Carbon Coolant Expansion Tank Cap Cover - Gloss Carbo...
affirm Starting At 0% APR - Subject To Eligibility. See Lending Terms
AUTOTECKNIC - Corporate Logo
T#:39497984
Part#: BM-0803-GC
Ships in 7 Business Days
$ 74.99 USD
Free Shipping on orders $49 and up
Turner Motorsport offers the AutoTecknic Dry Carbon Coolant Expansion Tank Cap Cover - Gloss Carbon as the perfect addition for BMW owners looking to elevate their engine bay’s appearance with premium materials and precision engineering.
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BMW Black Auxiliary Coolant Reservoir Cap
affirm Starting At 0% APR - Subject To Eligibility. See Lending Terms
Precision Raceworks - Corporate Logo
T#:38128031
Part#: 201-0394-BLK
Ships in 9 Business Days
$ 99.99

This product was last offered at the strikethrough price on
01-22-2026

$ 94.99 USD
Free Shipping on orders $49 and up
$ 94.99 USD
Free Shipping on orders $49 and up

BMW Black Auxiliary Coolant Reservoir Cap is the perfect upgrade for BMW owners looking to enhance both the aesthetics and functionality of their engine bay. Unlike generic aftermarket caps that overlook critical pressure regulation, this precision-engineered cap retains the OEM pressure release functionality, ensuring safe and reliable coolant system performance.

Crafted from high-quality billet aluminum, this reservoir cap offers superior durability and resistance to heat and fluids, preventing warping or degradation over time. Unlike adhesive-based cap covers that can loosen or fall off, this cap is a direct replacement for the factory component, providing a secure, high-performance solution.

  • OEM pressure release functionality – Maintains proper system regulation for optimal coolant performance
  • Premium billet aluminum construction – Offers enhanced durability and longevity
  • Direct replacement design – Secure fit without adhesives or modifications
  • Resistant to heat and fluids – Ensures long-lasting reliability in extreme conditions
  • Performance-inspired look – Adds a sleek, high-end appearance to your engine bay
  • Upgraded durability – Prevents cracking, leaks, and premature wear

Upgrade your BMW’s cooling system with the BMW Black Auxiliary Coolant Reservoir Cap, blending performance, reliability, and premium styling.

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BMW Blue Auxiliary Coolant Reservoir Cap
affirm Starting At 0% APR - Subject To Eligibility. See Lending Terms
Precision Raceworks - Corporate Logo
T#:38128029
Part#: 201-0394-BLU
Ships in 9 Business Days
$ 99.99

This product was last offered at the strikethrough price on
01-22-2026

$ 94.99 USD
Free Shipping on orders $49 and up
$ 94.99 USD
Free Shipping on orders $49 and up

BMW Blue Auxiliary Coolant Reservoir Cap is the perfect upgrade for BMW owners looking to enhance both the aesthetics and functionality of their engine bay. Unlike generic aftermarket caps that overlook critical pressure regulation, this precision-engineered cap retains the OEM pressure release functionality, ensuring safe and reliable coolant system performance.

Crafted from high-quality billet aluminum, this reservoir cap offers superior durability and resistance to heat and fluids, preventing warping or degradation over time. Unlike adhesive-based cap covers that can loosen or fall off, this cap is a direct replacement for the factory component, providing a secure, high-performance solution.

  • OEM pressure release functionality – Maintains proper system regulation for optimal coolant performance
  • Premium billet aluminum construction – Offers enhanced durability and longevity
  • Direct replacement design – Secure fit without adhesives or modifications
  • Resistant to heat and fluids – Ensures long-lasting reliability in extreme conditions
  • Performance-inspired look – Adds a sleek, high-end appearance to your engine bay
  • Upgraded durability – Prevents cracking, leaks, and premature wear

Upgrade your BMW’s cooling system with the BMW Blue Auxiliary Coolant Reservoir Cap, blending performance, reliability, and premium styling.

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