BMW Coolant Expansion Tanks for BMW 3 Series G20 (2019+)

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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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ECS Tuning Aluminum Coolant Bleeder Screw
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ECS - Corporate Logo
T#:363070
Part#: 003530ECS01A
Ships on Aug 8, 2025
Sale - Save 40% $ 33.99
$ 20.39 USD
Free Shipping on orders $49 and up
Sale - Save 40% $ 33.99
$ 20.39 USD
Free Shipping on orders $49 and up

Replace the flimsy plastic bleeder screw used in the coolant expansion tank or in one of the cooling system hoses with this high quality, durable, aluminum bleeder screw. The stock plastic screw can deform over time due to heat or even regular use. We have even seen the head of the screw snap off, leaving the threaded body stuck in the expansion tank. This aluminum screw will help to prevent sudden failure of the bleeder screw, which can result in immediate overheating of the car.

ECS Tuning's Aluminum Coolant Bleeder Screw replaces Genuine BMW Part Number 17111712788

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Genuine BMW - Corporate Logo
T#:29699315
Part#: 17135A1BD89
In Stock
Sale - Save 5% $ 28.99
$ 27.41 USD
Free Shipping on orders $49 and up
Sale - Save 5% $ 28.99
$ 27.41 USD
Free Shipping on orders $49 and up


Genuine BMW Cover Lid
This item fits the following BMW Chassis:
E70 X5M,E71 X6M,E70 X5,E71 X6,F01,F02,F06,F10,F12,F13,F15,F16,F30,F80 M3,F82 M4,F83,i3i12

Vargas Turbo Technologies - Corporate Logo
T#:7530036
Part#: COOLANTCAPBLUE
In Stock
$ 78.99 USD
Free Shipping
$ 78.99 USD
Free Shipping
VTT is proud to offer their billet replacement for the factory plastic Coolant Reservoir cap. This cap does away with the weak plastic cap while adding some pop, and color to your engine bay. This coolant cap retains ALL of the factory provisions by simply allowing you to snap the factory pressure-relief into the new Billet Cap. VTT also designed these caps to complement their N5X Billet Oil caps, N5XBillet Oil filter housing caps, and Billet Power Steering cap, so all 4 will have the same design. These caps are offered in 4 colors – Red, Black, Blue, and Clear anodized Replaces Genuine BMW Reservoir Cap # 17117639020 Note: Fitment includes 99% of all BMW with a coolant Reservoir tank from the E series forward, meaning then fit even the brand New G8X M3/4 with the S58, all B58, etc. If your BMW is an E90 or newer this cap most likely will fit
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VTT Billet Coolant Reservoir Cap - Anodized Clear - Most BMWs 2006+ (...
This coolant cap retains ALL of the factory provisions by simply allowing you to snap t...
Vargas Turbo Technologies - Corporate Logo
T#:7530035
Part#: COOLANTCAPRAW
Ships in 3 Business Days
$ 78.99 USD
Free Shipping
$ 78.99 USD
Free Shipping
VTT is proud to offer their billet replacement for the factory plastic Coolant Reservoir cap. This cap does away with the weak plastic cap while adding some pop, and color to your engine bay. This coolant cap retains ALL of the factory provisions by simply allowing you to snap the factory pressure-relief into the new Billet Cap. VTT also designed these caps to complement their N5X Billet Oil caps, N5XBillet Oil filter housing caps, and Billet Power Steering cap, so all 4 will have the same design. These caps are offered in 4 colors – Red, Black, Blue, and Clear anodized Replaces Genuine BMW Reservoir Cap # 17117639020 Note: Fitment includes 99% of all BMW with a coolant Reservoir tank from the E series forward, meaning then fit even the brand New G8X M3/4 with the S58, all B58, etc. If your BMW is an E90 or newer this cap most likely will fit
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Genuine MINI - Corporate Logo
T#:28337931
Part#: 17135A1BD89
In Stock
Sale - Save 7% $ 25.99
$ 24.20 USD
Free Shipping on orders $49 and up
Sale - Save 7% $ 25.99
$ 24.20 USD
Free Shipping on orders $49 and up
Vargas Turbo Technologies - Corporate Logo
T#:7530034
Part#: COOLANTCAPRED
In Stock
$ 79.99 USD
Free Shipping
$ 79.99 USD
Free Shipping
VTT is proud to offer their billet replacement for the factory plastic Coolant Reservoir cap. This cap does away with the weak plastic cap while adding some pop, and color to your engine bay. This coolant cap retains ALL of the factory provisions by simply allowing you to snap the factory pressure-relief into the new Billet Cap. VTT also designed these caps to complement their N5X Billet Oil caps, N5XBillet Oil filter housing caps, and Billet Power Steering cap, so all 4 will have the same design. These caps are offered in 4 colors – Red, Black, Blue, and Clear anodized Replaces Genuine BMW Reservoir Cap # 17117639020 Note: Fitment includes 99% of all BMW with a coolant Reservoir tank from the E series forward, meaning then fit even the brand New G8X M3/4 with the S58, all B58, etc. If your BMW is an E90 or newer this cap most likely will fit
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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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Vargas Turbo Technologies - Corporate Logo
T#:7530033
Part#: COOLANTCAPBLK
Ships in 10 Business Days
$ 79.99 USD
Free Shipping
$ 79.99 USD
Free Shipping
VTT is proud to offer their billet replacement for the factory plastic Coolant Reservoir cap. This cap does away with the weak plastic cap while adding some pop, and color to your engine bay. This coolant cap retains ALL of the factory provisions by simply allowing you to snap the factory pressure-relief into the new Billet Cap. VTT also designed these caps to complement their N5X Billet Oil caps, N5XBillet Oil filter housing caps, and Billet Power Steering cap, so all 4 will have the same design. These caps are offered in 4 colors – Red, Black, Blue, and Clear anodized Replaces Genuine BMW Reservoir Cap # 17117639020 Note: Fitment includes 99% of all BMW with a coolant Reservoir tank from the E series forward, meaning then fit even the brand New G8X M3/4 with the S58, all B58, etc. If your BMW is an E90 or newer this cap most likely will fit
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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 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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2 Pin Connector
10X Entries For Our Spin To Win Sweepstakes!
ECS - Corporate Logo
T#:33412932
Part#: 61132359999
Ships on Aug 11, 2025
Sale - Save 35% $ 9.99
$ 6.49 USD
Free Shipping on orders $49 and up
Sale - Save 35% $ 9.99
$ 6.49 USD
Free Shipping on orders $49 and up

Includes connector housing with terminals and seals. Commonly used for the coolant level sensor.

ECS Tuning replacement harness connectors include all necessary pins and wire seals for a complete harness repair. Whether you have a broken harness connector or need a complete wiring repair, we have the components you need.

Each connector includes an additional terminal in case one becomes lost or damaged during installation.

*OEM cross reference PN# 61132359999 - Commonly used for the coolant level sensor.

Please reference the original part number from the existing connector to confirm fitment, before ordering.

Suggested tools:

Suggested crimping pliers: T#387193
Wire De-pin tools:
12pc De-Pin Tool Set - T#386379
23pc De-Pin Tool Set - T#641943

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