BMW Coolant Expansion Tanks for BMW 5 Series G30 (2017+)

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On certain models, namely E36, E46, and E90, the factory BMW expansion tank is prone to either breaking at connection points or blowing apart altogether. If you're starting to feel like your expansion tank is on borrowed time, it's probably time to replace with either a direct OE replacement, or strengthen your cooling setup with an aluminum expansion tank - we offer numerous performance upgrades for your expansion tank. Especially if you're someone who likes to track your BMW, we recommend upgrading your expansion tank to avoid ruining your track day.
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Burger Motorsports - Corporate Logo
T#:38621407
Part#: BMS-TCBS
In Stock
New Item
$ 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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BMW Black Engine Coolant Reservoir Cap
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Precision Raceworks - Corporate Logo
T#:38161688
Part#: 201-0393-BLK
Ships Jul 10, 2025
New Item
$ 115.99 USD
Free Shipping on orders $49 and up

BMW Black Engine Coolant Reservoir Cap is a premium upgrade designed to enhance both the functionality and aesthetics of your BMW’s engine bay. Unlike flimsy plastic OEM caps, this high-performance cap is CNC-machined from durable billet aluminum, providing long-lasting strength and a sleek, motorsport-inspired look.

Built with precision, this cap retains the essential OEM pressure release function, ensuring proper cooling system operation without compromise. Unlike inferior adhesive covers that may detach over time, this cap fully replaces the factory component, delivering a secure and reliable fit. With a corrosion-resistant black anodized finish, it withstands extreme temperatures and harsh conditions while elevating your BMW’s under-hood appearance.

  • OEM pressure regulation – Maintains factory-designed pressure release for optimal cooling performance
  • CNC-machined billet aluminum – Provides exceptional durability and long-term reliability
  • Direct replacement – Fully replaces the stock cap, ensuring a perfect fit without modifications
  • Corrosion-resistant anodized finish – Prevents wear and adds a stealthy, high-performance look
  • Heat and fluid-resistant design – Built to withstand extreme temperatures and coolant exposure
  • Enhanced engine bay styling – Offers a sleek, motorsport-inspired upgrade

Upgrade your BMW’s cooling system with the BMW Black Engine Coolant Reservoir Cap, designed for superior performance and long-lasting durability.

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BMW Blue Engine Coolant Reservoir Cap
2X Entries For Our Spin To Win Sweepstakes!
Precision Raceworks - Corporate Logo
T#:38161689
Part#: 201-0393-BLU
Ships Jul 1, 2025
New Item
$ 115.99 USD
Free Shipping on orders $49 and up

BMW Blue Engine Coolant Reservoir Cap is the perfect upgrade for BMW owners looking to enhance both the performance and appearance of their engine bay. Constructed from high-quality billet aluminum, this cap replaces the flimsy plastic factory cap, offering improved durability and a sleek, high-performance aesthetic.

Designed with precision, this coolant reservoir cap incorporates the OEM pressure relief function to maintain proper cooling system operation. Unlike inferior stick-on covers that may loosen over time, this cap is a complete replacement, ensuring a secure, leak-free fit. The blue anodized finish provides superior corrosion resistance, making it a reliable upgrade for daily drivers and track enthusiasts alike.

  • OEM pressure relief function – Ensures proper cooling system performance and safety
  • Billet aluminum construction – Provides enhanced durability and strength over factory plastic caps
  • Direct-fit replacement – Fully replaces the stock cap for a precise, secure fit
  • Blue anodized finish – Resists corrosion, heat, and wear for long-lasting performance
  • Motorsport-inspired design – Adds a sleek, professional look to the engine bay
  • Built for longevity – Engineered to withstand extreme temperatures and coolant exposure

Upgrade your BMW’s cooling system with the BMW Blue Engine Coolant Reservoir Cap, designed for superior reliability and style.

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BMW Black Auxiliary Coolant Reservoir Cap
2X Entries For Our Spin To Win Sweepstakes!
Precision Raceworks - Corporate Logo
T#:38128031
Part#: 201-0394-BLK
Ships Jul 10, 2025
New Item
$ 99.99 USD
$ 99.99 USD

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
2X Entries For Our Spin To Win Sweepstakes!
Precision Raceworks - Corporate Logo
T#:38128029
Part#: 201-0394-BLU
Ships Jul 10, 2025
New Item
$ 99.99 USD
$ 99.99 USD

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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Silver Auxiliary Coolant Reservoir Cap
2X Entries For Our Spin To Win Sweepstakes!
Precision Raceworks - Corporate Logo
T#:38128032
Part#: 201-0394-SIL
Ships Jul 10, 2025
New Item
$ 99.99 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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BMW Silver Engine Coolant Reservoir Cap
2X Entries For Our Spin To Win Sweepstakes!
Precision Raceworks - Corporate Logo
T#:38161691
Part#: 201-0393-SIL
Ships Jul 10, 2025
New Item
$ 115.99 USD
Free Shipping on orders $49 and up

BMW Silver Engine Coolant Reservoir Cap is a premium upgrade for BMW owners looking to enhance both the performance and appearance of their engine bay. Crafted from high-strength billet aluminum, this cap replaces the factory plastic version, offering superior durability and a refined, professional look.

Designed with functionality in mind, it integrates the OEM pressure relief system to ensure your engine's cooling system remains safe and efficient. Unlike adhesive covers, which can peel or wear over time, this cap is a direct-fit replacement, providing a secure and leak-proof seal. The silver anodized finish not only enhances the visual appeal but also ensures resistance to corrosion, high temperatures, and wear, making it perfect for daily driving and track use.

  • OEM pressure relief integration – Maintains proper cooling system performance and reliability
  • Durable billet aluminum – Outperforms factory plastic caps in longevity and strength
  • Precision-machined for perfect fitment – Replaces the stock cap securely, not just a cover
  • Anodized silver finish – Offers corrosion, heat, and wear resistance
  • Elevates engine bay aesthetics – Adds a clean, professional appearance
  • Built for both street and track use – Designed to withstand extreme conditions

Enhance your BMW’s cooling system with the BMW Silver Engine Coolant Reservoir Cap, providing both style and functionality for years to come.

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Bremmen Parts - Corporate Logo
T#:36032339
Part#: 17117639020
Ships on Aug 11, 2025
New Item
$ 13.99 USD
Free Shipping on orders $49 and up

Expansion Tank
2X Entries For Our Spin To Win Sweepstakes! We Price Match - Give Us A Call or Chat!
Meyle - Corporate Logo
T#:36201637
Part#: 17139846642
Special Order: No Guaranteed ETA
New Item
$ 149.99 USD
$ 149.99 USD
The Expansion Tank plays a crucial role in your vehicle’s cooling system, managing coolant expansion and contraction caused by temperature changes. It provides additional space for the coolant, preventing overheating and maintaining the cooling system's efficiency. **Key Benefits:** - **Prevents Overheating:** Regulates coolant expansion and pressure to maintain stable engine temperatures. - **Durable Construction:** Built with heat-resistant materials to endure extreme engine conditions. - **OEM Compatibility:** Precisely designed to meet or exceed original equipment standards for an easy, seamless replacement. - **Leak-Proof Design:** Features a secure seal to prevent leaks and ensure optimal system performance. - **Enhanced Engine Longevity:** Promotes proper coolant circulation, reducing engine wear and tear. The Expansion Tank is an essential component for sustaining your vehicle's cooling system and ensuring reliable engine performance over time.
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