BMW Cooling System Parts & Accessories for BMW G01 X3 xDrive30i B46 2.0L

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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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Genuine BMW - Corporate Logo
T#:48780791
Part#: 11515A74E79
In Stock
New Item
2% off MSRP $ 133.99

MSRP stands for Manufacturer's Suggested Retail Price. This is the suggested retail price provided by the manufacturer, supplier or seller.

$ 130.99 USD
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2% off MSRP
$ 133.99

MSRP stands for Manufacturer's Suggested Retail Price. This is the suggested retail price provided by the manufacturer, supplier or seller.

$ 130.99 USD
Free Shipping on orders $49 and up
Genuine BMW replacement coolant flange for back of water pump housing
Bremmen Parts - Corporate Logo
T#:27205374
Part#: 11118511205
In Stock
Sale - Save 20% $ 42.99

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

$ 34.39 USD
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Sale - Save 20%
$ 42.99

This product was last offered at the strikethrough price on
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$ 34.39 USD
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Precision Raceworks - Corporate Logo
T#:38128032
Part#: 201-0394-SIL
Ships in 8 Business Days
$ 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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Precision Raceworks - Corporate Logo
T#:38161691
Part#: 201-0393-SIL
Ships in 9 Business Days
$ 109.99 USD
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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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Precision Raceworks - Corporate Logo
T#:38161688
Part#: 201-0393-BLK
Ships in 10 Business Days
$ 109.99 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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Precision Raceworks - Corporate Logo
T#:38128029
Part#: 201-0394-BLU
Ships in 10 Business Days
$ 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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Precision Raceworks - Corporate Logo
T#:38128031
Part#: 201-0394-BLK
Ships in 10 Business Days
$ 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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Precision Raceworks - Corporate Logo
T#:47679257
Part#: 622-0291-BLAK
Ships in 10 Business Days
New Item
$ 184.99 USD
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$ 184.99 USD
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The Precision Raceworks Billet Coolant Cap Set is a functional and stunningly stylish way to add a nice touch to any engine bay! These caps come in three color options, so there is always a color that will work for you! Black with Billet Silver, Black with Blue, and the Stealth series (all black). Many people don't realize it, but the OEM caps have a pressure release valve built into them. Oftentimes, aftermarket companies don't know this either or just don't care. But our team cares about proper function just as much as we care about the appearance of every product we design. For pressure relief, our caps incorporate the OEM internals, so you get all the functionality of the original caps, ensuring a safe and reliable system in place. These caps offer superior style and performance-grade components that guarantee a reliable fit every time. Durable billet aluminum construction provides long-lasting protection and dependability that will upgrade your engine bay for years to come. PLEASE NOTE: These do require assembly and swapping the pressure relief valves from your old caps to your new billet caps.
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Coolant Cap Bundle - Silver
For model years up to 2023
Precision Raceworks - Corporate Logo
T#:47679259
Part#: 622-0291-SIL
Ships in 10 Business Days
New Item
$ 184.99 USD
Free Shipping on orders $49 and up
$ 184.99 USD
Free Shipping on orders $49 and up
The Precision Raceworks Billet Coolant Cap Set is a functional and stunningly stylish way to add a nice touch to any engine bay! These caps come in three color options, so there is always a color that will work for you! Black with Billet Silver, Black with Blue, and the Stealth series (all black). Many people don't realize it, but the OEM caps have a pressure release valve built into them. Oftentimes, aftermarket companies don't know this either or just don't care. But our team cares about proper function just as much as we care about the appearance of every product we design. For pressure relief, our caps incorporate the OEM internals, so you get all the functionality of the original caps, ensuring a safe and reliable system in place. These caps offer superior style and performance-grade components that guarantee a reliable fit every time. Durable billet aluminum construction provides long-lasting protection and dependability that will upgrade your engine bay for years to come. PLEASE NOTE: These do require assembly and swapping the pressure relief valves from your old caps to your new billet caps.
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Meyle - Corporate Logo
T#:50066859
Part#: 17135A6A030
In Stock
New Item
$ 75.99 USD
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Replaces cracked or aged coolant expansion tank.
OEM Elring Water Pump Gasket - BMW Gen1 B46/B48 2.0L
For vehicles with the earlier Gen1 B46 / B48 engine only
Elring - Corporate Logo
T#:45483624
Part#: B07.530
Ships on Sep 21, 2026
$ 7.99 USD
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$ 7.99 USD
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If your water pump has to be removed or is already leaking coolant, it is important to replace the gaskets to prevent coolant loss and overheating.
ECS - Corporate Logo
T#:33412932
Part#: 61132359999
In Stock
Sale - Save 25% $ 10.99

This product was last offered at the strikethrough price on
06-14-2026

$ 8.24 USD
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Sale - Save 25%
$ 10.99

This product was last offered at the strikethrough price on
06-14-2026

$ 8.24 USD
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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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Vemo - Corporate Logo
T#:49578587
Part#: V20-99-1310
Special Order: No Guaranteed ETA
New Item
$ 182.99 USD
Free Shipping on orders $49 and up
Modern BMW thermostats are electronically controlled, allowing the DME/ECU to directly regulate coolant flow throughout the engine and its components. This system enables the thermostat to operate based on a broader range of temperature inputs, such as coolant, cylinder head, engine block, and oil temperatures, for more refined control of engine warm-up and temperature across diverse conditions. Unlike traditional thermostats, which simply open or close to permit coolant flow, this system uses a rotary valve for more dynamic control. The rotary valve adjusts to various positions, allowing for partial or full coolant flow to designated passageways as needed. This precision control helps your BMW's engine reach optimal temperatures quickly and ensures efficient heat management under various driving conditions.
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Vargas Turbo Technologies - Corporate Logo
T#:7530033
Part#: COOLANTCAPBLK
Back Ordered
$ 79.99 USD
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$ 79.99 USD
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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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URO - Corporate Logo
T#:27372124
Part#: 11537644811
Ships in 2 Business Days
$ 265.99 USD
Free Shipping on orders $49 and up

BMW B46 B48 Thermostat With Housing And Gasket is an essential component for maintaining optimal engine performance and cooling efficiency. This high-quality thermostat comes complete with housing and gasket, ensuring a precise fit and reliable operation.

The thermostat plays a crucial role in regulating the flow of coolant based on engine temperature. By controlling this flow, it helps maintain the engine at its optimal operating temperature, preventing overheating and ensuring efficient performance.

  • Complete Assembly: Includes thermostat, housing, and gasket for easy installation.
  • Optimal Cooling: Regulates coolant flow to maintain proper engine temperature.
  • Enhanced Performance: Ensures your engine operates within its ideal temperature range.
  • Durable Construction: Made with high-quality materials for long-lasting reliability.

Ensure your BMW's cooling system is functioning correctly with this reliable thermostat assembly from Turner Motorsport.

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OEM Rein Coolant Expansion Tank Overflow Hose - BMW G01 G02 Gen1 B46/...
For early models with the Gen1 B46/B48 engine - Not for vehicles with the later TU engines
Rein - Corporate Logo
T#:45757470
Part#: 17125A022D6
Ships in 2 Business Days
$ 35.99 USD
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$ 35.99 USD
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This hose connects the expansion tank to the radiator. If your coolant expansion tank hose is cracked or leaking, replace it early to prevent further coolant loss and eventual overheating.

Schwaben - Corporate Logo
T#:384260
Part#: 015326SCH01A
In Stock
Sale - Save 29% $ 20.99

This product was last offered at the strikethrough price on
05-02-2026

$ 14.99 USD
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Sale - Save 29%
$ 20.99

This product was last offered at the strikethrough price on
05-02-2026

$ 14.99 USD
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Straighten bent fins in heat exchangers like radiators, condensers, and intercoolers obstruct air flow and reduce heat transfer. Paper-thin fins are easily bent, even by slight pressure.
Schwaben - Corporate Logo
T#:377131
Part#: 004170SCH01A
In Stock
Sale - Save 55% $ 63.99

This product was last offered at the strikethrough price on
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$ 28.79 USD
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Sale - Save 55%
$ 63.99

This product was last offered at the strikethrough price on
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$ 28.79 USD
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These pliers feature a spring loaded clamp with a 24" cable and will lock onto the clamp and hold open for easy removal. These pliers are designed to remove metal or plastic self-tightening hose clamps with diameters from 11/16" to 2-1/2" ( 18 to 54mm).
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Bav Auto Tools - Corporate Logo
T#:580395
Part#: B8800082
In Stock
Sale - Save 15% $ 32.99

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

$ 28.04 USD
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$ 32.99

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$ 28.04 USD
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Multiple adapters include to fit a variety of vehicles.
Bav Auto Tools - Corporate Logo
T#:580348
Part#: B8800019
In Stock
Sale - Save 20% $ 29.99

This product was last offered at the strikethrough price on
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$ 23.99 USD
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Sale - Save 20%
$ 29.99

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$ 23.99 USD
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Used to remove your fan clutch

Bav Auto Tools - Corporate Logo
T#:580379
Part#: B8800058
In Stock
Sale - Save 25% $ 32.99

This product was last offered at the strikethrough price on
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$ 24.74 USD
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Sale - Save 25%
$ 32.99

This product was last offered at the strikethrough price on
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$ 24.74 USD
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Angled jaws close, creating a complete seal every time you use them - the jaws are offset, making it possible to use in hard-to-reach locations. Made of glass-filled nylon for extra strength. These are perfect for use with brake lines, etc.
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Victor Reinz - Corporate Logo
T#:580584
Part#: C32348
Ships in 7 Business Days
$ 3.99

This product was last offered at the strikethrough price on
05-07-2026

$ 2.99 USD
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$ 2.99 USD
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Gear Wrench - Corporate Logo
T#:387079
Part#: KDT3977
Ships in 2 Business Days
$ 53.99 USD
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This tool is a variation of our popular 3976 Flat Band Hose Clamp Pliers and features 45º jaws with swivel tips to grip at any angle and pliers that latch securely in position.
ATD Tools - Corporate Logo
T#:3657943
Part#: ATD3601
Ships in 2 Business Days
$ 59.99 USD
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Always have extra o-rings


ATD Tools - Corporate Logo
T#:3629267
Part#: ATD3300
Ships in 7 Business Days
$ 497.99 USD
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$ 497.99 USD
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Adapters for most European and domestic vehicles
Schwaben - Corporate Logo
T#:402498
Part#: 024948SCH01A
In Stock
Sale - Save 25% $ 115.99

This product was last offered at the strikethrough price on
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$ 86.99 USD
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$ 115.99

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$ 86.99 USD
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The Schwaben Coolant Vacuum Fill Tool ensures no air pockets get into your cooling system while you're replacing your coolant - intended for use to refill your cooling system, not for removal. Can be used with Schwaben fluid extractors or with shop air - standard air compressor with a minimum rating of 90 PSI (6.2 bar). Includes all fittings and adapters necessary for use, with a molded storage case to keep your Schwaben Vacuum Fill Tool pristine for future use.
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CTA Tools - Corporate Logo
T#:641679
Part#: CTAA195
Ships on Sep 21, 2026
$ 9.98 USD
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Tests all ethylene glycol solutions with radiator hot or cold

CTA Tools - Corporate Logo
T#:641760
Part#: CTAA878
Ships on Sep 21, 2026
$ 23.57 USD
Free Shipping on orders $49 and up
Use to remove and install Fan Clutch Assemblies when replacing Water Pumps or doing other Engine Services

Schwaben - Corporate Logo
T#:362940
Part#: 003466SCH01
Ships on Sep 1, 2026
Sale - Save 20% $ 109.99

This product was last offered at the strikethrough price on
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$ 87.99 USD
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$ 109.99

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$ 87.99 USD
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When it comes to BMW's we all know the weak point is commonly in the cooling system, many models proving hard to bleed the air pockets out after the refresh. The coolant refill tool solves this problem, ensuring that you get an air pocket free fill. The entire task is as simple as draining the system like normal, reinstalling the drain plugs and hooking the tool up to your refill location. The reason this tool works so well is due to the venturi valve, it converts air pressure from the compressor to vacuum inside the cooling system, then with a twist of a valve sucks coolant right into the system using the vacuum pressure.
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Schwaben - Corporate Logo
T#:379950
Part#: 009787SCH01A
In Stock
Sale - Save 15% $ 39.99

This product was last offered at the strikethrough price on
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$ 33.99 USD
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$ 39.99

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$ 33.99 USD
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Schwaben Locking Hose Pinch-Off Pliers have adequate clamping force to effectively seal large or pressurized cooling system hoses. These pliers are ideal for clamping shut most hoses, ensuring reliability in your automotive tasks. With swivel jaws, they provide even clamping force, making them a versatile tool for various applications.

  • Adequate clamping force for large or pressurized hoses
  • Ideal for clamping shut most hoses
  • Swivel jaws ensure even clamping force
  • Versatile tool for automotive maintenance

WARNING: This product contains chemicals known to the state of California to cause cancer, birth defects, and/or reproductive harm. For more information, visit http://www.p65warnings.ca.gov.

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Bav Auto Tools - Corporate Logo
T#:580397
Part#: B8800084
In Stock
Sale - Save 15% $ 146.99

This product was last offered at the strikethrough price on
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$ 124.94 USD
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$ 146.99

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$ 124.94 USD
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Schwaben - Corporate Logo
T#:391482
Part#: 014710SCH01A
In Stock
Sale - Save 25% $ 205.99

MSRP stands for Manufacturer's Suggested Retail Price. This is the suggested retail price provided by the manufacturer, supplier or seller.

$ 154.49 USD
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Sale - Save 25%
$ 205.99

This product was last offered at the strikethrough price on
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$ 154.49 USD
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Are you refreshing your coolant system or having issues with coolant loss? An easy way to test your system for leaks and ensure you're able to maintain pressure without coolant loss is the Schwaben Cooling System Pressure Tester Kit.
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