BMW Cooling System Parts & Accessories for BMW 3 Series E46 (1999-2005)

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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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Wahler - Corporate Logo
T#:341054
Part#: 11537509227
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$ 70.99 USD
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$ 70.99 USD
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Stop leaks before they start with this new Thermostat With Housing from Wahler. Despite the fact that most BMW models are brilliant, most have common issues that can plague you during your ownership of the car. This part is one of those issues, as they are known to crack over time. This replacement part is perfect stop a crack and possibly a leak before it starts.
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Mahle-Behr - Corporate Logo
T#:341098
Part#: 11537509227
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$ 103.84 USD
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Replacement stock MAP thermostat with plastic housing and gasket for E46, E39, E60, X5, Z4 - M54 engine, M52TU engine. Your car may still operate fine according the instrument display but the electrically-operated thermostat may be going bad. This new thermostat includes the thermostat gasket, ready to install in your BMW.

Hailing from Stuttgart, Mahle-Behr specializes in automotive cooling systems. From air conditioning to engine cooling M-B has you covered with OE-quality replacement parts.

Applications:
1999-2003 E39 528i, 525i, 530i sedan, touring wagon (M52TU engine, M54 engine)
1999-2005 E46 323, 328, 325, 330 sedan, coupe, cabrio, touring wagon (M52TU engine, M54 engine)
2004-2005 E60 525i, 530i sedan, touring wagon (M54 engine)
2001-2006 E53 X5 3.0 (M54 engine)
2004-2006 E83 X3 2.5i X3 3.0i (M54 engine)
1999-2002 Z3 2.3. Z3 2.5i, 2.8 Z3 3.0i (M54 engine)
2003-2005 Z4 2.5i, Z4 3.0 (M54 engine)

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Turner Motorsport - Corporate Logo
T#:18003818
Part#: 008363LA02
In Stock
$ 499.99

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$ 331.02 USD
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Our Turner Motorsport's full aluminum expansion tank was designed and engineered in house to help with the weak point in your E46 cooling system. The coolant expansion tank goes through heat cycles over and over again from regular driving, it is important that your expansion tank is doing its job to retain coolant to keep your engine operating temperatures down and keep your engine bay clean. Not only is this a major upgrade but also a great maintenance item to replace. Our expansion tank was designed to fit the OEM hoses for an easy install and comes with all the upgraded items you will need for a clean install.

If your BMW needs a new expansion tank, make sure this is the last expansion tank you ever need to buy. Our coolant expansion tank has a full aluminum construction and wrinkle black powder coat for durability. Expansion tank kit comes with all the accessories you need to replace your expansion tank once, and never have to worry about it again.

Product Features:

Maintains stock coolant capacity and expansion volume
Designed to maintain OE coolant elevation, preventing air pockets
Baffled tank ensures that air pockets cannot be introduced during aggressive driving and provides accurate coolant level reading
Carefully designed bleed passage prevents the introduction of air as the engine cools
Turner engraved internal fill level
TIG welded 5052 aluminum construction
All bungs are machined to fit factory hose ends
Kit contents:

Turner Aluminum Expansion Tank
Coolant level sensor
Expansion tank cap
Flared coolant pressure release line
Hardware for installation
Product Development:

Turner expansion tanks are designed, engineered, tested and quality inspected by our Research and Development team at Turner. Nothing but the highest level of precision and quality through leading-edge product development technology including FARO laser scanning for reverse engineering and quality inspection, SolidWorks 3D CAD modeling, rapid prototyping utilizing our in-house 3D printer and rigorous long term product testing.

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Turner Motorsport - Corporate Logo
T#:37014879
Part#: 008682LA02
In Stock
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$ 347.99 USD
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BMWs are well-known for their problematic cooling systems, which are often a catalyst for irreversible engine damage and a hefty repair bill. The coolant expansion tank—a crucial component responsible for holding hot engine coolant under high pressure—is a common cause of cooling system issues. Unfortunately, BMW chose to manufacture the factory E46 M3 expansion tank out of plastic. After years of exposure to high coolant temperatures, ambient engine bay heat, and chemical-rich antifreeze, the plastic degrades, eventually weakening enough to fail catastrophically.

With this issue in mind, our team of BMW enthusiasts engineered the ultimate cooling system upgrade for E46 M3 owners: a heavy-duty expansion tank built to last! Crafted from durable 5052 TIG-welded aluminum, this tank resists high temperatures and pressures without degrading over time. Unlike the fragile OEM plastic tank, Turner’s design eliminates the risk of cracking, leaking, or failure. Upgrade to our Heavy Duty Aluminum Expansion Tank Kit and say goodbye to expansion tank issues for good!

To guarantee exact fitment, the upgraded tank was designed using advanced 3D CAD modeling. All bungs, nipples, and fittings are precision-machined to ensure a secure seal with factory hose ends. Unlike other aftermarket options, this tank maintains the factory coolant capacity and includes our laser-cut logo plate at the top, providing an accurate fill level. Internal baffles are incorporated to prevent fluid cavitation, eliminating air pockets in the cooling system and avoiding false coolant level warnings during spirited driving.

Engineered for high-performance builds and daily drivers alike, this expansion tank boasts a premium wrinkle black powder coat finish for a clean "OEM+" aesthetic. This tough coating not only enhances appearance but also protects against corrosion for long-term durability. The kit includes a silicone overflow hose, a high-quality level sensor, and an OE expansion tank cap, offering a complete cooling system upgrade. Avoid the risks of the factory expansion tank—upgrade your E46 M3 today and drive with confidence!

Features & Benefits:

Durable 5052 TIG-Welded Aluminum Construction: Ensures long-term reliability and eliminates expansion tank failure. Premium Wrinkle Black Powder Coat Finish: Offers an "OEM+" appearance while preventing corrosion. Factory Coolant Capacity Retention: Maintains the same coolant level as the original design. Laser-Cut Turner Logo Plate: Provides a clear and accurate fill level indicator. Internal Baffles: Prevent the introduction of air pockets during high-performance driving. Precision-Machined External Bungs and Fittings: Ensure a perfect fit for factory hose connections. Kit Includes:

Turner Motorsport Aluminum Expansion Tank Performance Silicone Coolant Overflow Hose Expansion Tank Cap Coolant Level Sensor Product Development:

Our Heavy Duty Aluminum Expansion Tank was designed, engineered, tested, and quality inspected by our Research & Development team. Our development process includes leading-edge product technology: FARO laser scanning for reverse engineering and quality inspection, SolidWorks 3D CAD modeling, rapid prototyping utilizing our in-house 3D printer, and rigorous long-term product testing.

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ECS - Corporate Logo
T#:363070
Part#: 003530ECS01A
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$ 26.99 USD
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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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ECS - Corporate Logo
T#:363707
Part#: 001977ECS03A
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Most of the pulleys on your BMW engine are plastic, which become brittle and frail over time and from engine bay heat. A failed pulley could leave you stranded which is why it is vital to inspect the pulleys during routine maintenance. This is an aluminum version of the stock water pump pulley used on the M50/M52/M52TU/M54 engine in the E36, E46, Z3, Z4, and other models. It uses the same hardware and the original belt as the stock plastic pulley. But the aluminum will last much longer.
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ECS - Corporate Logo
T#:638748
Part#: 006205LA09
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$ 149.24 USD
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Unlike factory rubber hoses, silicone can withstand higher temperatures and pressures with minimal wear. Rubber will wear out and weaken so don't let it bite you when it counts! Silicone has been proven during extreme racing conditions and won't be the weak link that ruins your day. This kit is specifically designed for the enthusiast that wants uprated cooling hoses, but also wants to address the heat-cycled plastic connectors and O-rings that are also prone to failure in higher mileage or older vehicles.Kit includes a brand new pair of connectors. This E46 NM ECS silicone hose set replaces two hoses - Upper Radiator Hose - 17127510952 Lower Radiator Hose - 11531436408
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ECS - Corporate Logo
T#:378149
Part#: 003631ECS01
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Unlike factory rubber hoses, silicone can withstand higher temperatures and pressures with minmal wear. Rubber will wear out and weaken so don't let it bite you when it counts! Silicone has been proven during extreme racing conditions and won't be the weak link that ruins your day.

This kit is specifically designed for the enthusiast that wants uprated cooling hoses, but also wants to address the heat-cycled plastic connectors and o-rings that are also prone to failure in higher mileage or older vehicles.

This E46 M3 ECS silicone hose set replaces two hoses - 
11537830716, upper radiator hose 
11537830715, lower radiator hose 

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ECS - Corporate Logo
T#:367060
Part#: 002778ECS01
Ships on Dec 7, 2026
Sale - Save 10% $ 100.99

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$ 90.89 USD
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Most of the pulleys on your BMW engine are plastic, which become brittle and frail over time and from engine bay heat. A failed pulley could leave you stranded which is why it is vital to inspect the pulleys during routine maintenance. This is an aluminum version of the stock water pump pulley used on the S54 engine in the E46 M3, MZ3, and Z4M. It's the same size and uses the same hardware and the original belt as the stock plastic pulley. But the aluminum will last much longer.
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ECS - Corporate Logo
T#:393542
Part#: 013178ECS
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$ 119.99 USD
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The ECS Exact-fit water line is a perfect upgrade if you're tired of dealing with brittle failure prone parts under your hood. The reinforced fluorosilicone hose has been pre-formed to route the same way your stock line did so you can maintain that clean factory installed appearance. Upgrading the line fitting with a billet aluminum piece eliminates the failure prone plastic fitting giving your cooling system strength.

Included:

Aluminum fitting

  • Material: 6061-T6 Aluminum - MIL-A-8625F Type II Class 2 black anodized for superior corrosion resistance and strength
  • Single-piece design avoiding additional interfaces that may cause leaks
  • Matches OEM style connection to upper coolant hose

Silicone hose

  • Material: Black Reinforced Fluorosilicone Lined Coolant Safe Silicone
  • Pre-formed hose to ensure OEM style routing and appearance
  • Can maintain the use of your stock retaining clips to route the hose in identical locations (due to slight variations in silicone the retainer on the expansion tank may not fit)
  • Pressure tested to ensure 2X operating pressures to ensure reliability
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ECS - Corporate Logo
T#:377877
Part#: 003402ECS07A-05
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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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ECS - Corporate Logo
T#:639004
Part#: 006205LA01
Ships on Sep 28, 2026
Sale - Save 25% $ 160.99

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Unlike factory rubber hoses, silicone can withstand higher temperatures and pressures with minimal wear. Rubber will wear out and weaken so don't let it bite you when it counts! Silicone has been proven during extreme racing conditions and won't be the weak link that ruins your day. This kit is specifically designed for the enthusiast that wants uprated cooling hoses, but also wants to address the heat-cycled plastic connectors and O-rings that are also prone to failure in higher mileage or older vehicles.Kit includes a brand new pair of connectors. This E46 NM ECS silicone hose set replaces two hoses - Need new connectors included, check out (T#638748) Upper Radiator Hose - 17127510952 Lower Radiator Hose - 11531436408
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ECS - Corporate Logo
T#:341684
Part#: 003402ECS06A-12
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$ 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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ECS - Corporate Logo
T#:341280
Part#: 003402ECS06A-08
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$ 2.99 USD
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ECS Tuning 304 Stainless Steel Hose Clamps

Revolutionize your car maintenance with ECS Tuning's premium 304 stainless steel hose clamps. Eliminate dealership delays and inflated prices! These German-style clamps utilize T-bolts for hassle-free diameter adjustment. With various band widths available, these durable clamps ensure reliability without the hefty cost. Experience dealership-quality products at affordable rates, exclusively at ECS Tuning.

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ECS - Corporate Logo
T#:304266
Part#: 003402ECS06A-03
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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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ECS - Corporate Logo
T#:363017
Part#: 003402ECS06A-11
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Upgrade your BMW with ECS Tuning's Stainless Steel Hose Clamps, designed for convenience and durability. With various band widths and German-style T-bolts, these clamps offer easy adjustment to your required diameter. Say goodbye to dealer pricing and enjoy the quality you love at ECS Tuning.

  • Full stainless steel construction
  • Various band widths available
  • German-style T-bolts for easy adjustment
  • Convenient solution for hose clamp replacement
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ECS - Corporate Logo
T#:341281
Part#: 003402ECS06A-13
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$ 4.19 USD
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ECS Tuning 304 Stainless Steel Hose Clamps

Once again, ECS Tuning has found a way to make life easier for working on your car. Need new hose clamps but don't want to wait to order it from the dealership or pay more than you should for a hose clamp? That's where we come in! These are full 304 stainless steel hose clamps with various band widths for your convenience. They are German style using T-bolts to adjust in size to your required diameter. Never pay dealer pricing again, but still get the quality you love here at ECS Tuning.

  • Made from high-quality 304 stainless steel for durability
  • German-style design with T-bolts allows for easy size adjustment
  • Various band widths for versatile use
  • Avoid dealership pricing without compromising on quality
  • Perfect for BMW enthusiasts seeking affordable yet reliable hose clamps
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ECS - Corporate Logo
T#:385425
Part#: 003402ECS05A-06
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Upgrade Your BMW Maintenance with Stainless Steel Hose Clamps from ECS Tuning

ECS Tuning introduces premium full stainless steel hose clamps, offering superior quality and convenience for your BMW maintenance. Avoid dealership delays and overpricing by choosing from a selection of band widths, ensuring you receive top-quality hose clamps without overpaying.

Key Benefits:

  • Premium full stainless steel hose clamps
  • Various band widths for enhanced convenience
  • High-quality alternative to dealership pricing
  • Readily available stock eliminates waiting time
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ECS - Corporate Logo
T#:377836
Part#: 003402ECS05A-10
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ECS Tuning Stainless Steel Hose Clamps for BMW

Upgrade your BMW's hose clamps with ECS Tuning Stainless Steel Hose Clamps, designed for convenience and durability. Say goodbye to long waits and overpriced dealership clamps. With various band widths available, these stainless steel clamps ensure a secure fit for your vehicle's hoses.

Benefits:

  • Convenient replacement for worn-out hose clamps
  • Made of durable stainless steel for long-lasting performance
  • Available in various band widths for versatile use
  • Affordable alternative to dealership pricing
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ECS - Corporate Logo
T#:380416
Part#: 003402ECS07A-03
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Ensure a tight and leak-free seal in your BMW's cooling, vacuum, or intake systems by installing a new adjustable hose clamp. Over time, clamps can deform or lose their tightness due to aging or frequent removal, potentially causing leaks in your coolant or vacuum hoses. Avoid the risk of leaks by replacing old clamps with new hardware, offering peace of mind against coolant and vacuum system issues.

Key benefits of the adjustable hose clamp include:

  • Maintaining a secure and leak-free seal in your BMW's systems.
  • Preventing coolant or vacuum leaks that can affect performance.
  • Adjustable size from 70mm to 78mm for versatile applications.

Upgrade your hose clamps to ensure optimal performance and reliability in your BMW's systems.

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Bavarian Autosport - Corporate Logo
T#:12544802
Part#: 11531437040
In Stock
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05-03-2026

$ 84.99 USD
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The plastic thermostat cover in your BMW is a known point of failure. Throughout years of repeated contact with hot coolant, the plastic can crack and cause massive coolant leaks and potential overheating. Eliminate one of the weak links in your cooling system with a replacement aluminum thermostat housing. By installing this aluminum unit, you have no worries as far as plastic housing cracks go
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Bavarian Autosport - Corporate Logo
T#:640208
Part#: 17117639022
In Stock
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$ 11.89 USD
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This radiator expansion tank cap is used most BMW's from 1991-2006. It is a common failure item. When this item fails, it cannot hold pressure which results in your BMW overheating. If you are overhauling your coolant system, now is the time to consider preventative replacing this cap. It is also referred to as the coolant reservoir cap. From 1974 to 2019, Bavarian Autosport was one of the premier vendors for BMW and MINI auto parts. We are happy to preserve the Bav Auto legacy by continuing to carry their high-quality products into the future. All Bav Auto parts will remain unchanged in design and sourced from the same OEM suppliers to ensure long-lasting reliability. We trust these parts, accessories, and upgrades so confidently that we back every Bavarian Autosport branded component with a 2-year warranty.
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Bavarian Autosport - Corporate Logo
T#:640496
Part#: 17137787039
In Stock
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We have found that the expansion tanks should be replaced based on age as well as condition. Expansion tanks seem to have a lifespan of less than six years before they show signs of fatigue and wear. Pre-emptively replacing the expansion tank as part of an overall maintenance plan can prevent you from getting stranded from a sudden failure later on. From 1974 to 2019, Bavarian Autosport was one of the premier vendors for BMW and MINI auto parts. We are happy to preserve the Bav Auto legacy by continuing to carry their high-quality products into the future. All Bav Auto parts will remain unchanged in design and sourced from the same OEM suppliers to ensure long-lasting reliability. We trust these parts, accessories, and upgrades so confidently that we back every Bavarian Autosport branded component with a 2-year warranty.
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Bremmen Auxiliary Fan Temperature Switch - E46 E39 E9X E60 E70 E53 ...
Mounted in upper radiator hose, controls operation of auxiliary fan Mounted in lower radiator hose, controls operation of auxiliary fan
Bremmen Parts - Corporate Logo
T#:640141
Part#: 13621433077
In Stock
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$ 16.79 USD
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The auxiliary fan switch activates the auxiliary cooling fan to provide additional cooling under high heat loads, and when the car is stationary


Bavarian Autosport - Corporate Logo
T#:638088
Part#: 17111436250
In Stock
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This Bav Auto part is the mounting bracket from the radiator to the expansion tank on an E46 3 series with a Manual Transmission. From 1974 to 2019, Bavarian Autosport was one of the premier vendors for BMW and MINI auto parts. We are happy to preserve the Bav Auto legacy by continuing to carry their high-quality products into the future. All Bav Auto parts will remain unchanged in design and sourced from the same OEM suppliers to ensure long-lasting reliability. We trust these parts, accessories, and upgrades so confidently that we back every Bavarian Autosport branded component with a 2-year warranty.
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Bavarian Autosport - Corporate Logo
T#:638085
Part#: 11537502525
In Stock
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$ 40.79 USD
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This plastic water pipe is positioned directly underneath your intake manifold. Due to its plastic construction, it is notorious for catastrophic failure. Rapid cooling loss and overheating are both direct results of this failure, posing permanent and lasting damage to the engine.

Replace your cracked/broken coolant pipe with this high-quality Bavarian Autosport component to ensure long-term reliability and perfect fitment.

From 1974 to 2019, Bavarian Autosport was one of the premier vendors for BMW and MINI auto parts. We are happy to preserve the Bav Auto legacy by continuing to carry their high-quality products into the future. All Bav Auto parts will remain unchanged in design and sourced from the same OEM suppliers to ensure long-lasting reliability. We trust these parts, accessories, and upgrades so confidently that we back every Bavarian Autosport branded component with a 2-year warranty.

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Bavarian Autosport - Corporate Logo
T#:638080
Part#: 11531705210
In Stock
Sale - Save 20% $ 40.99

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$ 32.79 USD
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This is the plastic heater inlet pipe that connects the cylinder head to the heater inlet on cars with the M52 or M54 engine. The plastic on this hose becomes brittle over time and eventually leads to failure. Replace yours with a brand new Bav Auto Heater inlet pipe to prevent catastrophic failure.
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Bremmen Parts - Corporate Logo
T#:640204
Part#: 17127510952
In Stock
Sale - Save 21% $ 34.99

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05-03-2026

$ 27.74 USD
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$ 34.99

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Replacement Upper Radiator Hose for E46 3 series (Non-M3). We recommend replacing the Coolant Temperature Sensor while replacing this hose as the original sensor is often damaged while trying to remove it from the old hose. From 1974 to 2019, Bavarian Autosport was one of the premier vendors for BMW and MINI auto parts. We are happy to preserve the Bav Auto legacy by continuing to carry their high-quality products into the future. All Bav Auto parts will remain unchanged in design and sourced from the same OEM suppliers to ensure long-lasting reliability. We trust these parts, accessories, and upgrades so confidently that we back every Bavarian Autosport branded component with a 2-year warranty.
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Bav Auto Expansion Tank Mounting Plate - E46 Non-M w/ Auto Trans ...
For vehicles with an automatic transmission only
Bavarian Autosport - Corporate Logo
T#:638089
Part#: 17111436251
In Stock
Sale - Save 20% $ 45.99

This product was last offered at the strikethrough price on
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$ 36.79 USD
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$ 45.99

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This Bav Auto part is the mounting bracket from the radiator to the expansion tank on E46 3 series and E85/E86 Z4 with an Automatic Transmission. From 1974 to 2019, Bavarian Autosport was one of the premier vendors for BMW and MINI auto parts. We are happy to preserve the Bav Auto legacy by continuing to carry their high-quality products into the future. All Bav Auto parts will remain unchanged in design and sourced from the same OEM suppliers to ensure long-lasting reliability. We trust these parts, accessories, and upgrades so confidently that we back every Bavarian Autosport branded component with a 2-year warranty.
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Bremmen Parts - Corporate Logo
T#:640203
Part#: 11531436408
In Stock
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$ 31.20 USD
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$ 36.99

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OEM Replacement Lower Radiator Hose for E46 3 series (Non-M3). We recommend replacing the Coolant Temperature Sensor while replacing this hose as the original sensor is often damaged while trying to remove it from the old hose. From 1974 to 2019, Bavarian Autosport was one of the premier vendors for BMW and MINI auto parts. We are happy to preserve the Bav Auto legacy by continuing to carry their high-quality products into the future. All Bav Auto parts will remain unchanged in design and sourced from the same OEM suppliers to ensure long-lasting reliability. We trust these parts, accessories, and upgrades so confidently that we back every Bavarian Autosport branded component with a 2-year warranty.
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Bremmen Parts - Corporate Logo
T#:26494584
Part#: 11537509227
In Stock
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$ 49.99 USD
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Bavarian Autosport - Corporate Logo
T#:15511839
Part#: 17111707817
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$ 15.19 USD
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Connects the radiator to the expansion tank

Bremmen Parts - Corporate Logo
T#:36913373
Part#: 17117561757
In Stock
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$ 169.99 USD
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$ 169.99 USD

The auxiliary fan in your vehicle serves an extremely important role. When your car reaches temperatures that may be hazardous to your engine, the auxiliary fan moves air through the radiator to provide better cooling. Usually activated during times of stationary vehicle operation, it supplements the air usually driven through the radiator by driving down the road.

If your vehicle is getting too hot during traffic or at stop lights, your auxiliary fans are probably faulty. Replace yours with this piece from Bremmen Parts to restore the factory cooling in your vehicle and prevent catastrophic damage to your engine. Even if your fans are still operational but the blades are damaged or cracked, replacement is the only solution.

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Bremmen Parts - Corporate Logo
T#:38655188
Part#: 11537830715
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$ 22.53 USD
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Bremmen Parts - Corporate Logo
T#:38621424
Part#: 64218363198
Ships in 6 Business Days
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$ 8.66 USD
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Bremmen Parts - Corporate Logo
T#:36981061
Part#: 11537502000
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$ 29.74 USD
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Water pipes play a crucial role in maintaining proper engine cooling. If cracked, they must be replaced immediately to prevent engine overheating. This water pipe runs from the rear of the water pump housing to the expansion tank hose. It comes complete with all necessary seals for a hassle-free installation.
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Bremmen Parts - Corporate Logo
T#:640149
Part#: 11521712058
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$ 18.76 USD
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This fan is driven by the serpentine belt, engaged by the fan clutch. If you have bad motor mounts, it's quite common for the blades of this fan to make contact with the radiator or radiator shroud, essentially self-destructing the fan into many pieces. Be sure to get a new fan clutch, while you are replacing this.
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Bremmen Parts - Corporate Logo
T#:36981065
Part#: 11517838159
Ships on Dec 2, 2026
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$ 110.97 USD
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$ 138.99

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A failing water pump is a recipe for engine overheating and costly internal damage. Keep your coolant flowing and your engine protected by replacing your aging pump with this high-quality OE unit from Bremmen Parts.

Water pump replacement is suggested at 60,000 - 80,000 miles.

This pump includes the alignment dowel, sealing gasket, and thermostat sealing o-ring. We recommend picking up a water pipe sealing o-ring (11537830712) and thermostat (11531318274) for a comprehensive service.

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Bremmen Parts - Corporate Logo
T#:36981064
Part#: 11531436406
In Stock
$ 31.99

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$ 24.99 USD
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$ 31.99

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Over time, prolonged exposure to high-temperature coolant can take a toll on your vehicle's hoses. Made from reinforced rubber, these hoses are prone to wear and failure in various ways, including splitting at hose clamps, swelling, cracking, or breaking. Any of these issues can lead to coolant loss and potentially leave you stranded. Replacing your hoses at the first sign of wear is essential to maintaining a properly functioning cooling system.

This replacement hose is designed with the correct diameter, bends, and length for a precise fit, making it an ideal solution for swelled or damaged hoses. With straightforward installation, this hose provides peace of mind, whether you're embarking on a long road trip or simply commuting to work.

When replacing your radiator hose, some coolant loss is unavoidable. Browse our website to find the exact replacement coolant and other parts for your vehicle, delivered straight to your door. Don’t forget to order a new thermostat housing as well—factory plastic units often crack or warp during removal, and replacing them ensures a complete and reliable repair.

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Genuine BMW - Corporate Logo
T#:1474
Part#: 82141467704
In Stock
6% off MSRP $ 29.97

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

$ 28.21 USD
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6% off MSRP
$ 29.97

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

$ 28.21 USD
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The use of Original BMW Anti-Freeze/Coolant will ensure sufficient cooling in summer and protection against freeze-ups in winter. BMW Antifreeze/Coolant will also guard your vehicle's various engine components against corrosion.
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Stewart Components - Corporate Logo
T#:3780
Part#: 888010330
In Stock
$ 219.99

This product was last offered at the strikethrough price on
06-15-2026

$ 204.99 USD
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This high performance water pump is a direct replacement pump designed to fit a wide range of BMW engines with no modifications. That includes accepting the Factory Fan Clutch. The front of the BMW High Performance Water Pump is stock appearing giving it that classic BMW look while the back is all business. Features up to 20% increase of water flow over stock pump, and it TWICE as efficient as factory pump, much less parasitic drag than other pumps, stainless steel impeller, heavy duty bearing, high quality water seal. Manufactured by EMP / Stewart Components. THIS PUMP COMES WITH A LIMITED LIFETIME WARRANTY

Fits all US Spec M50/52/54 and S50/52 6 cylinder engines including:
E36 chassis 1992-1999 325,328, 323 and M3
E46 chassis 1999-2005 323,325,328 &330
E34 chassis 1991-1995 525i
E39 chassis 1997-2003 525i, 528i & 530i
E53 X5 SAV 1999-2003 6 cylinder models
Z3 2.8 and 3.0 6 cylinder engines.
Z4 (Not M) including Z4 2.5 & 3.0
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Genuine BMW - Corporate Logo
T#:7436
Part#: 17111712963
In Stock
$ 1.99 USD
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The most common use for this rivet is to secure the radiator fan shroud to the radiator. This rivet can also be used on a wide variety of other applications as well.

When doing any sort of repair or maintenance there is no replacement for genuine factory parts. Turner Motorsport carries the Genuine BMW brand with pride and has the parts you need to complete your next project with confidence.
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Genuine BMW - Corporate Logo
T#:367933
Part#: 17222245358
In Stock
$ 3.99 USD
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Upgrade your BMW's oil or transmission cooling system with the Turner Motorsport Genuine O-Ring, part number 17222245358. This high-quality O-ring is designed to provide a reliable seal, ensuring optimal performance and preventing leaks in your BMW's vital systems. Additionally, it is compatible with MINI applications, where it is commonly used on the end of the parking brake cable.

  • Genuine BMW part for guaranteed quality and compatibility
  • Prevents leaks in the oil and transmission cooling systems
  • Ensures optimal performance of vital components
  • Compatible with MINI applications for versatile use
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Genuine BMW - Corporate Logo
T#:6533
Part#: 07129952104
In Stock
$ 3.99 USD
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GENUINE BMW HOSE CLAMP 07129952104

Geba - Corporate Logo
T#:341052
Part#: 11517527910
In Stock
$ 105.99

This product was last offered at the strikethrough price on
02-27-2026

$ 62.99 USD
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$ 62.99 USD
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The early M50/M52 engines had a serious weak point: the water pump. BMW originally used a plastic impeller in the waterpump. This would degrade over time and eventually break apart. Your car overheats immediately. This water pump is an updated one with a metal impeller. BMW has since released a water pump with a composte impeller that does not have the same issues and is just as reliable as the metal impeller version. But for piece of mind, the metal impeller is tough to beat.

Geba builds all of their pumps to exceed factory specifications by using a metal impeller. This offers a huge improvement over stock and a massive increase in reliability. Servicing all major European models, Geba has you covered when it comes time for a new water pump.

This waterpump fits the following BMWs:
1999-2006  E46 BMW  323i, 323Ci, 328i, 328Ci, 325i, 325Ci, 325xi, 330i, 330Ci, 330xi
1997-2003  E39 BMW  528i, 525i, 530i
2004-2010  E83 BMW  X3 2.5i & 3.0i
2000-2006  E53 BMW  X5 3.0i
1997-2002  Z3 BMW  Z3 2.8, Z3 2.5, Z3 3.0, MZ3 (S52)
2003-2005  E85 BMW  Z4 2.5i & Z4 3.0i
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URO Premium - Corporate Logo
T#:587673
Part#: 17111712788PRM
In Stock
$ 5.75

This product was last offered at the strikethrough price on
02-25-2026

$ 5.35 USD
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$ 5.35 USD
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Having an operational bleeder screw for your coolant system assures that when service is performed, all air pockets are removed. Having air pockets in your coolant system prevents your system from functioning properly. Your heat may not work as well and there is the potential for engine overheating if the air pocket is trapped behind the thermostat. Be sure that all of the air is bled out of your system with a new bleeder screw.
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Mahle-Behr - Corporate Logo
T#:2766
Part#: 17111742231
Ships in 3 Business Days
$ 20.99

This product was last offered at the strikethrough price on
08-12-2026

$ 19.99 USD
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$ 19.99 USD
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This radiator expansion tank cap is used most BMW's from 1991-2006. It is a common failure item. When this item fails, it cannot hold pressure which results in your BMW overheating. If you are overhauling your coolant system, now is the time to consider preventative replacing this cap. It is also referred to as the coolant reservoir cap.

Hailing from Stuttgart, Mahle-Behr specializes in automotive cooling systems. From air conditioning to engine cooling M-B has you covered with OE-quality replacement parts.

This item fits the following BMWs:
1990-1991 E30 BMW 318i 318is 318ic
1992-1998 E36 BMW 318i 318is 318ic 323is 323ic 325i 325is 325ic 328i 328is M3
1999-2005 E46 BMW 323i 323ci 325i 325ci 325xi 328i 328ci 330i 330ci 330xi M3
1989-1995 E34 BMW 530i 535i 540i M5
1991-1995 E34 BMW 525i
1997-2003 E39 BMW 525i 528i 530i 540i M5
1989-1994 E32 BMW 735i 735il 740i 740il 750il
1995-2001 E38 BMW 740i 740il 750il
2002-2008 E65 BMW 745i 745li 750i 750li 760i 760li
1990-1998 E31 BMW 840i 840ci 850i 850ci 850csi
2004-2011 E83 BMW X3 2.5i X3 3.0i X3 3.0si
2000-2006 E53 BMW X5 30.0i X5 4.4i X5 4.6is X5 4.8is
1996-2002 Z3 BMW Z3 1.9 Z3 2.3 Z3 2.5i Z3 2.8 Z3 3.0i M Coupe M Roadster
2003-2008 E85 BMW Z4 2.5i Z4 3.0i Z4 3.0si M Roadster M Coupe
2000-2003 E52 BMW Z8 Z8 Alpina
2007+ E90 BMW 335i & 335xi
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Turner Motorsport - Corporate Logo
T#:338927
Part#: HOSE-CLAMPS
In Stock
Sale - Save 3% $ 3.99

This product was last offered at the strikethrough price on
06-13-2026

Starting at $ 3.87 USD
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$ 3.99

This product was last offered at the strikethrough price on
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Hose clamps for radiator hoses, coolant hoses, vacuum hoses, or intake hoses. These hose clamps are the same style as your OEM hoses with a smooth inside band to prevent cutting into the hose material.
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Genuine BMW - Corporate Logo
T#:11526
Part#: 82142209769
In Stock
$ 10.60 USD
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This 1 liter bottle is perfect for topping of the coolant in your BMW. This is The use of Original BMW Anti-Freeze/Coolant will ensure sufficient cooling in summer and protection against freeze-ups in winter. BMW Antifreeze/Coolant will also guard your vehicle's various engine components against corrosion. BMW Anti-Freeze/ Coolant will prevent excessive silicate gel precipitation, which may cause plugging of the cooling system and lead to more extensive repairs.
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Redline - Corporate Logo
T#:3607
Part#: 1-WW-12Z
In Stock
$ 15.99 USD
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Water Wetter is a unique wetting agent for cooling systems which reduces coolant temperatures by as much as 30*F. This liquid product can be used to provide rust and corrosion protection in plain water for racing engines, which provides much better heat transfer properties than glycol-based antifreeze. Or it can be added to new or used antifreeze to improve the heat transfer of ethylene and propylene glycol systems. Designed for modern aluminum, cast iron, copper, brass, and bronze systems.

We have been using RedLine Oil in our street cars and race cars for years. Hands-down, it is the Number One brand of high performance lubricant for BMWs.
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