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BMW Coolant Expansion Tanks

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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Heavy Duty Aluminum Expansion Tank Kit - E46 M3 S54
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Turner Motorsport - Corporate Logo
T#:37014879
Part#: 008682LA02
In Stock
Sale - Save 20% $ 434.99

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

$ 347.99 USD
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Sale - Save 20%
$ 434.99

This product was last offered at the strikethrough price on
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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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Turner Heavy Duty Aluminum Expansion Tank Kit - E8X E9X N20/N52/N54 ...
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Turner Motorsport - Corporate Logo
T#:12806793
Part#: 008378LA02
In Stock
Sale - Save 20% $ 479.99

This product was last offered at the strikethrough price on
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$ 383.99 USD
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Sale - Save 20%
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$ 383.99 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 N52/N54 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
Heavy duty bleeder screw
Flared coolant pressure release line
Hardware for installation

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Silicone Expansion Tank Relocation Heater Hose
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Turner Motorsport - Corporate Logo
T#:21735881
Part#: 053082LA01
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$ 56.99 USD
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Upgraded or replacement silicone heater hose for our N54 expansion tank relocation kits.

60" silicone performance coolant hose featuring a molded 90-degree bend for installs with space constraints.

Features and benefits:

Constructed of 4-Ply reinforced silicone for improved durability over the failure-prone rubber hoses.
Reduced thermal conductivity
Improved resistance to ozone and UV degradation for improved performance and durability.
Turner branded

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Turner Motorsport Aluminum Coolant Expansion Tank Relocation Kit - E9...
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Compatible with hotside and coldside (OE location) intakes
Turner Motorsport - Corporate Logo
T#:568369
Part#: 021942TMS13
Ships on Aug 25, 2026
Sale - Save 15% $ 815.99

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$ 693.59 USD
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Hotside intakes are a very common modification for N54 powered BMWs. Here at Turner Motorsport, we found ourselves unsatisfied with all existing solutions to relocate the coolant expansion tank to the cold side of your engine bay, freeing up real estate on the hot side. We decided to make an end all be all solution for people looking to relocate your expansion tank that's compatible with both hotside intakes and factory location coldside intakes. All CAD designed in-house, our N54 aluminum expansion tank relocation kit allows you to seamlessly mount our new aluminum expansion tank on the cold side of your engine bay.
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Heavy Duty Aluminum Expansion Tank Kit - F80 M3, F82/F83 M4, F87 M2 C...
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Turner Motorsport - Corporate Logo
T#:49787642
Part#: 050595LA03
Ships on Aug 3, 2026
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BMWs are well-known for their problematic cooling systems, which are often the cause of 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 F8X 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 F80 M3, F82/F83 M4, and F87 M2 Competition owners: a heavy-duty expansion tank that is 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, our 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 S55-equipped BMW 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. Proprietary Coolant Level Sensor with Wiring Harness Adapter: Provides a plug-and-play, CEL-free functionality. Kit Includes:

Turner Motorsport Aluminum Expansion Tank Performance Silicone Coolant Overflow Hose 6mm Nipple Fitting Expansion Tank Cap Coolant Level Sensor Coolant Level Sensor Wiring Harness Adapter

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Turner Expansion Tank Wire Harness - E9X/ E8X N54
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Turner Motorsport - Corporate Logo
T#:568366
Part#: 021942TMS05
In Stock
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$ 20.24 USD
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The E9X/ E8X N54 Expansion Tank Wire harness is perfect for those running a relocated coolant reservoir tank. This harness plugs right into the factory connector allowing you to extend the position of the sensor without the need to splice any wires.
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Heavy Duty Aluminum Expansion Tank Kit - N55 E82/E88/E9X
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Turner Motorsport - Corporate Logo
T#:30031522
Part#: 050610LA02
Ships in 10 Business Days
Sale - Save 25% $ 457.99

This product was last offered at the strikethrough price on
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$ 343.49 USD
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$ 343.49 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 E9X N55 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 E82/88 and E90/92/93 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 N55-equipped BMW 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 Aluminum Coolant Bleeder Screw Ball Stud 6mm Fitting 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.

Installation:

To aid in the installation process, we've assembled a start-to-finish installation guide, including detailed instructions on removing your factory cooling expansion tank and associated components.

Click HERE for Installation Instructions

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S65 Heavy Duty Aluminum Expansion Tank Kit - E9x M3
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Turner Motorsport - Corporate Logo
T#:36981082
Part#: 054921LA02
In Stock
Sale - Save 15% $ 458.99

This product was last offered at the strikethrough price on
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$ 390.99 USD
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Sale - Save 15%
$ 458.99

This product was last offered at the strikethrough price on
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$ 390.99 USD
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BMW is well-known for its 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 E90 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 E90 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
Billet coolant bleeder screw
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.

Installation:

- Click HERE for Installation Instructions -

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Turner Motorsport HD Aluminum Coolant Expansion Tank Kit - M50/M52/S5...
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Turner Motorsport - Corporate Logo
T#:9998526
Part#: 008348LA01BKT
In Stock
Sale - Save 20% $ 423.99

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$ 339.19 USD
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This product was last offered at the strikethrough price on
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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 E36 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 E36 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.

Aluminum Coolant Expansion Tank 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
Heavy duty bleeder screw
Flared coolant pressure release line
Hardware for installation

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Turner Motorsport Aluminum Coolant Expansion Tank Relocation Kit - E8...
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Compatible with hotside and coldside (OE location) intakes
Turner Motorsport - Corporate Logo
T#:568368
Part#: 021942TMS14
Ships on Aug 25, 2026
Sale - Save 15% $ 815.99

This product was last offered at the strikethrough price on
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$ 693.59 USD
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Hotside intakes are a very common modification for N54 powered BMWs. Here at Turner Motorsport, we found ourselves unsatisfied with all existing solutions to relocate the coolant expansion tank to the cold side of your engine bay, freeing up real estate on the hot side. We decided to make an end all be all solution for people looking to relocate your expansion tank. All CAD designed in-house, our N54 aluminum expansion tank relocation kit allows you to seamlessly mount our new aluminum expansion tank on the cold side of your engine bay, featuring an integrated power steering pump reservoir mount. During the design process, we did everything possible to ensure no air pockets could develop in the cooling system even during spirited drives. The baffled tank is all TIG welded 5052 aluminum construction, featuring a carefully designed bleed passage. We also machined all of our bungs to accept OEM hose ends, to keep the fit and finish as OE+ as possible. Keeping with this same mindset, we made sure that coolant elevation matches OE exactly, and integrated a power steering pump reservoir mount. Our aluminum expansion tank accepts the OE coolant level sensor, bleeder screw, and coolant cap, but we include new ones with this kit, as we thought you should replace them during installation. See more about these features in the list below, and if you have any additional questions please feel free to call into our staff of skilled BMW enthusiasts at 1-800-280-6966. Find our Installation Guide HERE Features and benefits: TIG welded 5052 aluminum construction, wrinkle black powder coated Utilizes factory coolant capacity and expansion volume CAD designed to retain OE coolant elevation, which prevents air pockets Baffled tank ensures that air pockets will not be created under spirited driving conditions, and ensures accurate coolant level reading Meticulously designed bleed passage prevents air pockets while the engine cools All bungs machined for factory hose end compatibility (no barb fittings!) Integrated power steering reservoir mount Kit includes Turner Motorsport aluminum expansion tank, Turner Motorsport wiring harness, all necessary hoses, hardware, OE level sensor, bleeder screw, and coolant cap This product fits the following BMWs: 2008-2013 E82 135i 2007-2013 E88 135i
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Coolant Expansion Tank - E46 (non-M), X3, X5 3.0
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Packaged by Turner - Corporate Logo
T#:338020
Part#: 17117573781
In Stock at Vendor
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This coolant reservoir is for the non-M E46 3-series models from 1999-2006 (M3 takes a different expansion tank). 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. This is the most recent expansion tank design from Hella-Behr, the OEM supplier to BMW. It replaces the original BMW part number 17137787039.

Other items to consider replacing at the same time are the radiator cap, coolant level sensor, lower radiator hose, coolant temp sensor in the lower hose, and the hose clamps. If your car has an automatic transmission you should also replace the oil cooler thermostat in the radiator frame, which is a common source for leaks.

This coolant expansion tank fits:

1999-2006 E46 3 series - 323i, 323Ci, 325i, 325Ci, 325xi, 328i, 328Ci, 330i, 330Ci & 330xi (**no M)
2004-2008 X3 SAV - X3 2.5, X3 3.0, X3 3.0si
2000-2005 X5 SAV - X5 3.0
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OEM Coolant Expansion Tanks Kit - F22/23 F3X B48 B58
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Packaged by Turner - Corporate Logo
T#:27605427
Part#: 17138677649TKT
Ships on Oct 7, 2026
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Genuine BMW expansion tanks have a bad habit of failing after a few years. This has primarily been caused by the plastic construction of the expansion tanks. After enough heat cycles, the plastic becomes brittle and can crack, causing coolant to leak out and air to enter the coolant system. If a failing expansion tank is not addressed soon enough, the coolant loss can lead to an overheating engine. This kit includes two brand new high quality expansion tanks and caps
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Cooling System Refresh Kit - Level 2 - E9x, E82, E88, Z4
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Packaged by Turner - Corporate Logo
T#:42099868
Part#: 11537558523TKT
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Keep your BMW running at the proper temperature and avoid costly engine repairs with the Cooling System Refresh Kit, the complete maintenance solution trusted by enthusiasts and professionals alike.
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ECS Tuning Aluminum Coolant Bleeder Screw
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ECS - Corporate Logo
T#:363070
Part#: 003530ECS01A
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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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Bav Auto Coolant Expansion Tank - E36 E39 Z3 M50 M52 S50 S52 ...
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Bavarian Autosport - Corporate Logo
T#:638094
Part#: 17111723520
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$ 31.99 USD
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Replace your old expansion tank to prevent potential failure or leaks. Includes a brand new coolant level sensor. 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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ECS Exact-Fit Silicone Expansion Tank Hose - F-Chassis N55
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ECS - Corporate Logo
T#:37892077
Part#: 006402LA03
In Stock
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Over time, factory rubber hoses break down and eventually fail as a result of consistent exposure to chemical-rich antifreeze and hot engine bay temperatures. While all coolant hoses are prone to failure, the expansion tank hose is especially susceptible to failure. To fix this issue, ECS has created the ultimate performance hose upgrade! Crafted from heavy-duty, fiber-reinforced silicone, this ECS Exact-Fit Silicone Expansion Tank Hose withstands higher temperatures and greater pressure than the factory rubber alternative. Engineered to resist electrochemical degradation, it’s tested for continuous operation at 250°F and over 45 psi, ensuring improved reliability, enhanced flow, and reduced turbulence. To further improve upon the factory hose design, ECS engineers developed precision-machined billet aluminum "Quick Connect" hose ends. Unlike the OEM plastic counterparts, these robust components resist heat-induced failure, ensuring long-term durability and reliability. Replaces OEM Part Numbers: 17128570061, 17128507235. Installation is straightforward: begin by removing the factory overflow hose and retaining clips. Transfer the OEM metal clips from the factory connector to the new billet fittings, then press the fittings onto the expansion tank and upper coolant hose. The included silicone hose is routed through the OEM path and securely clamped onto the billet fittings. After installation, the fittings can stay in place, only the silicone needs to be removed for future maintenance. Key Benefits: Direct OEM Fitment – Retains factory hose routing while eliminating the weaknesses of rubber construction. High-Temperature Resistance – Silicone material withstands extreme heat and chemicals for long-term durability. 2-Ply, Fiber-Reinforced Fluorosilicone Construction – Provides superior resistance to glycol-based coolant and other harsh fluids. Upgraded Billet Aluminum Quick-Connect Ends – CNC-machined from 6061-T6 aluminum with integrated O-rings, ensuring a secure, leak-free connection that won’t degrade over time. Easy Installation – Includes stainless steel clamps for a hassle-free, bolt-on upgrade.
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Bav Auto Coolant Expansion Tank - E53 X5, E46, E83 X3
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Bavarian Autosport - Corporate Logo
T#:640496
Part#: 17137787039
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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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Bav Auto Expansion Tank Mounting Plate - E46 Non-M w/ Manual Trans ...
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T#:638088
Part#: 17111436250
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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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BMW N47 N55 Expansion Tank
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T#:17704781
Part#: 17137642160
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BMW N47 N55 Expansion Tank from Turner Motorsport is a high-quality replacement designed to address issues with cracked or damaged coolant expansion tanks. Engineered for durability and performance, this expansion tank ensures reliable cooling system function.

  • Durable Construction: Built to withstand high temperatures and pressure, ensuring long-term reliability.
  • Direct Replacement: Engineered as a precise fit for BMW N47 and N55 engines, making installation straightforward and hassle-free.
  • Enhanced Cooling Efficiency: Maintains optimal coolant levels and pressure for effective engine cooling.
  • High-Quality Materials: Manufactured from premium materials to resist cracking and leaks.
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Bav Auto Expansion Tank Mounting Plate - E46 Non-M w/ Auto Trans ...
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T#:638089
Part#: 17111436251
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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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Bav Auto Coolant Expansion Tank - BMW E90 335d M57 3.0L
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Bavarian Autosport - Corporate Logo
T#:640493
Part#: 17138570079
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Replace your damaged expansion tank to prevent coolant loss or potential overheating issues. 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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Coolant Expansion Tank
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T#:36032353
Part#: 17111741167
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Coolant Expansion Tank - E30 325e 325i thru 1987 528e thru 88 ...
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T#:2061
Part#: 17111707540
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This radiator expansion tank (coolant reservoir) is used on E30 325e 325es 325i 325is 325ic from 1984-1987 and E28 528e 1982-1987.

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.​

This item fits the following BMWs:
1984-1987 E30 BMW 325e 325es 325i 325is 325ic 325ix
1982-1988 E28 BMW 528e
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Engine Coolant Expansion Tank
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T#:30729009
Part#: 17138677649
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Coolant Expansion Tank - 17111436381
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T#:36303285
Part#: 17111436381
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BMW E39 Coolant Expansion Tank is an essential component designed to maintain the proper coolant level in your vehicle's cooling system. Manufactured with high-quality materials, this expansion tank ensures reliable performance and durability, preventing engine overheating by accommodating the expansion of coolant as it heats up. The kit includes a level sensor and cap, providing everything needed for a seamless installation. This expansion tank is specifically engineered to meet the exact specifications of your BMW E39, offering a perfect fit and optimal functionality.

Complete Kit: Includes level sensor and cap for easy installation. High-Quality Construction: Built with durable materials for long-lasting performance. Prevents Overheating: Helps manage coolant expansion, ensuring engine protection. Exact Fit: Designed to meet the precise specifications of your BMW E39. Enhanced Reliability: Ensures proper coolant level maintenance for optimal cooling system function.

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Bav Auto Coolant Expansion Tank - With Level Sensor - E70 X5, E71 X6 ...
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T#:638093
Part#: 17138621092
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Replace your old expansion tank to prevent potential failure or leaks. Includes a brand new coolant level sensor.
Expansion Tank - F90, F91, F92, F93
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T#:10225927
Part#: 17137889450
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Coolant Expansion Tank
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Bremmen Parts - Corporate Logo
T#:30728965
Part#: 17137823626
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Coolant Expansion Tank - E60 M5,E63 M6
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T#:22514
Part#: 17112283345
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This high quality Genuine BMW expansion tank is used on the S85 V10 engines, and is a common failure item. Be leary of competitors selling this part for less -- is it a Genuine BMW? Probably not. We only carry the Genuine BMW brand expansion tank as it is the only one we use in our own BMWs. If you are overhauling your coolant system, now is the time to consider preventative replacing this expansion tank. 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. While replacing the expansion tank we recommend replacing the level sensor (sold below) as these are also common failure items.

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.

This item fits the following BMWs:
2004-2010 E60 BMW M5
2004-2010 E63 BMW M6
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Coolant Expansion Tank W/ Cap
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T#:639188
Part#: 17137529273
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Genuine BMW Radiator Mounting Plate for Expansion Tank - Z4
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T#:45825
Part#: 17112248408
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Genuine BMW Mounting Plate -
This item fits the following BMW Chassis:
E85,E86

Fits BMW Engines including:
M54,N52

Bremmen Parts Water Pipe Connector - E83, Z4
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T#:1195932
Part#: 17112248409
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Located underneath the expansion tank

Heavy-Duty Expansion Tank With Mechanical Thermostat Conversion Kit &...
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T#:37419798
Part#: 008363LA02EB1KT
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Take your BMW’s cooling system to the next level with this Turner Motorsport Cooling Upgrade Kit. Featuring a Heavy-Duty Aluminum Expansion Tank and a Mechanical Thermostat Conversion Kit, this combo is engineered to deliver ultimate reliability and superior performance for M52TU/M54 engines. Say goodbye to the cooling system failures common in stock setups—Turner Motorsport has you covered.

Turner Motorsport M52TU/M54 Heavy-Duty Expansion Tank Kit

The Turner Motorsport Aluminum Expansion Tank is a premium upgrade designed to replace the fragile factory plastic tank, which is known to crack, leak, or even explode. Crafted for durability, this tank’s all-aluminum construction with wrinkle black powder coating ensures this is the last expansion tank you’ll ever need.

Why Upgrade? The factory plastic tanks on BMW M52TU/M54 engines are notorious for failure under heat and pressure. Avoid the risk of being stranded on the side of the road with a mess of coolant—Turner Motorsport’s aluminum expansion tank is built to withstand years of demanding use and intense heat cycles.

Key Features and Benefits:

Complete Kit: Includes Turner Aluminum Expansion Tank, coolant level sensor, expansion tank cap, and flared coolant pressure release line. OEM Fit & Capacity: Direct fit with no modifications, maintains stock coolant capacity and expansion volume. Baffled Design: Prevents air pockets during aggressive driving and ensures accurate coolant level readings. Premium Construction: TIG-welded 5052 aluminum with machined fittings for factory hose compatibility. Turner Motorsport M52TU/M54 Mechanical Thermostat Conversion Kit

Replace your problematic factory plastic thermostat housing with Turner Motorsport’s high-quality billet aluminum Thermostat Conversion Kit. This upgrade not only provides increased reliability but also allows for thermostat swaps to suit specific temperature requirements, making it ideal for daily drivers and track cars alike.

Why Make the Switch? The factory plastic thermostat housing with its built-in thermostat is prone to cracking and requires the whole unit to be replaced during maintenance. Turner’s conversion kit changes the game by providing a durable billet housing with a replaceable thermostat for flexibility and lower maintenance costs.

Key Features and Benefits:

Increased Reliability: Uses an M50/S50 mechanical thermostat, including an 80°C thermostat for enhanced cooling control. Customizable: Includes barbed hose connections for standard E46 M3 hoses and -16 ORB connections for custom hoses. Engineered to Last: CNC-machined from billet 6061 aluminum and black anodized for corrosion resistance. Enhanced Sealing: Features a Viton gasket for superior durability and sealing performance. Kit Includes:

6061 Billet Aluminum Thermostat Housing 80°C Mechanical Thermostat Thermostat Housing Gasket Thermostat Harness ECS Silicone E46 M3 Cooling Hoses Turner Motorsport Precision Engineering & Product Development

Every component in this cooling upgrade kit has been rigorously designed, engineered, and tested by Turner Motorsport’s Research and Development team. Using state-of-the-art technology such as FARO laser scanning, SolidWorks 3D modeling, and in-house rapid prototyping, Turner ensures that these products meet the highest standards of quality, precision, and durability.

Upgrade your BMW with confidence—Turner Motorsport is your partner in performance and reliability.

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Meyle Expansion Tank Cap
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T#:579357
Part#: 3148009004
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Replace worn or missing pieces.
Bremmen Coolant Bleeder Screw - BMW E30 E36 E38 E39 E46 E83 E90 Z4 ...
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T#:640140
Part#: 17111712788
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Plastic bleeder screw for cooling system is used to bleed air that would otherwise create an air pocket and lead to overheating. Includes o-ring seal.
Coolant Expansion Tank Cap
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Bremmen Parts - Corporate Logo
T#:36032339
Part#: 17117639020
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Febi Coolant level sensor - E36, E39
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T#:382276
Part#: 61318360855
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Monitors the coolant level in the expansion tank
Coolant Level Sensor
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T#:30728984
Part#: 61311378320
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Bav Auto Expansion Tank Cap - E36 E46 E34 E39 E32 E38 E65 X3 X5 Z4 ...
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T#:640208
Part#: 17117639022
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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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Bav Auto Coolant Level Sensor - BMW E36 E39 M50/52 S50/52
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T#:639793
Part#: 61318360855
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This is the sensor / sending unit that notifies the computer if your coolant level is low. When this fails, it can give a false indication of low coolant -- or worse, not inform you of a low coolant situation that could potentially cause overheating. 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 Coolant Expansion Tank - E53 X5, Z3 2.3 2.5i 2.8 3.0i ...
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Bremmen Parts - Corporate Logo
T#:640497
Part#: 17107514964
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This radiator expansion tank is used on E53 X5 4.4i and 4.6is with M62 engine, and Z3 2.3 2.5i 2.8 3.0i from 1999-2002. It is a common failure item as the plastic weakens over time and stress cracks will lead to coolant leaks. 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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Coolant Expansion Tank
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Bremmen Parts - Corporate Logo
T#:45723154
Part#: 17137642158
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2 Pin Connector
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ECS - Corporate Logo
T#:33412932
Part#: 61132359999
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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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Coolant Expansion Tank
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Bremmen Parts - Corporate Logo
T#:53044121
Part#: 17137601948
Ships on Sep 28, 2026
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Sale - Save 15% $ 72.99

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

$ 62.04 USD
Sale - Save 15%
$ 72.99

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

$ 62.04 USD

MINI F5X F6X Expansion Tank
affirm Starting At 0% APR - Subject To Eligibility. See Lending Terms
Bremmen Parts - Corporate Logo
T#:28138156
Part#: 17137617362
Special Order: No Guaranteed ETA
Sale - Save 5% $ 81.99

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

$ 77.51 USD
Free Shipping on orders $49 and up
Sale - Save 5%
$ 81.99

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

$ 77.51 USD
Free Shipping on orders $49 and up

MINI F5X F6X Expansion Tank

For Mini owners looking to maintain optimal engine performance, the MINI F5X F6X Expansion Tank is an essential component. This expansion tank ensures proper cooling system functionality, preventing overheating and potential engine damage. Crafted with high-quality materials, it guarantees durability and reliability for long-term use, providing peace of mind to Mini enthusiasts.

  • Ensures proper cooling system functionality
  • Prevents overheating and potential engine damage
  • Crafted with high-quality materials for durability
  • Provides peace of mind to Mini enthusiasts
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Bav Auto Coolant Expansion Tank - E60 E61 E63 E64 M54 N52 N62 ...
affirm Starting At 0% APR - Subject To Eligibility. See Lending Terms
Bavarian Autosport - Corporate Logo
T#:640491
Part#: 17137542986
Special Order: No Guaranteed ETA
Sale - Save 10% $ 54.99

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

$ 49.49 USD
Free Shipping on orders $49 and up
Sale - Save 10%
$ 54.99

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

$ 49.49 USD
Free Shipping on orders $49 and up
This Bav Auto cooling system expansion tank/coolant reservoir is a direct replacement for the factory unit. Replace your cracked or leaking radiator expansion tank today. 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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