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ECS BMW Cooling System Parts & Accessories for BMW E46 M3 S54 (1999-2005)

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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Band Hose Clamp | 12-20mm 3/8"/9mm

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T#:304266

Part#: 003402ECS06A-03

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06-13-2026

$ 3.74 USD

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Secure hoses in your BMW effortlessly with the ECS 3/8" / 9mm Band Hose Clamp (12-20mm). Specifically designed for BMW models, this clamp ensures a snug fit and reliable hold for hoses measuring between 12mm to 20mm. Crafted with durable materials, these clamps provide exceptional resistance against leaks and are ideal for various automotive applications. Upgrade your BMW's hose security with these reliable ECS hose clamps.

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3/8"/9mm Band Hose Clamp - 50-70mm

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T#:341684

Part#: 003402ECS06A-12

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06-13-2026

$ 5.24 USD

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Elevate your BMW maintenance with ECS Tuning's 304 stainless steel hose clamps, offering convenience and top-quality performance at an affordable price. Designed with various band widths and German-style T-bolts for adjustable sizing, these hose clamps ensure a secure fit for your specific diameter needs. Skip the dealership wait and excessive pricing; ECS Tuning provides reliable, dealership-quality hose clamps without the premium cost, ensuring your car receives the care it deserves.

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77-85mm - 3/4" Band Hose Clamp

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T#:377877

Part#: 003402ECS07A-05

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$ 19.49 USD

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Upgrade your BMW's hose clamps with the 77-85mm - 3/4" Band Hose Clamp from Turner Motorsport. These full 304 stainless steel clamps offer convenience and quality without the dealership price tag. German-style T-bolts allow for easy adjustment to your required diameter, ensuring a secure fit every time.

Made of durable 304 stainless steel for long-lasting performance
German-style T-bolt design for easy size adjustment
Convenient band widths for versatile applications
Quality alternative to dealership pricing

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Hose Clamp 2 5/16" - 3 1/4" - priced each

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T#:376806

Part#: 54155K23

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$ 4.99 USD

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$ 4.99 USD

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Hose Clamp 2 5/16" - 3 1/4"

Ensure secure hose connections with the Hose Clamp 2 5/16" - 3 1/4", a versatile and reliable solution for various applications. Crafted from durable materials, this clamp offers superior strength and corrosion resistance. Its adjustable design allows for a snug fit, reducing the risk of leaks and ensuring optimal performance. Upgrade your hose connections with the precision and reliability of the Hose Clamp 2 5/16" - 3 1/4".

Versatile and reliable solution for various applications
Superior strength and corrosion resistance
Adjustable design for a snug fit
Reduces risk of leaks for optimal performance

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2 Pin Connector

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T#:33412932

Part#: 61132359999

Ships on Jul 28, 2026

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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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ECS BMW Cooling System Parts & Accessories for BMW E46 M3 S54 (1999-2005)

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Band Hose Clamp | 12-20mm 3/8"/9mm

3/8"/9mm Band Hose Clamp - 50-70mm

77-85mm - 3/4" Band Hose Clamp

Hose Clamp 2 5/16" - 3 1/4" - priced each

Hose Clamp 2 5/16" - 3 1/4"

2 Pin Connector

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