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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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Turner Motorsport - Corporate Logo
T#:56327183
Part#: 060289LA02
In Stock
New Item
$ 349.99

This product was last offered at the strikethrough price on
07-23-2026

$ 329.99 USD
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$ 329.99 USD
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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 robust intercooler expansion tank that is built to last! Constructed from durable 5052 TIG-welded aluminum, this tank withstands high temperatures and pressures without deteriorating over time. Unlike the OEM molded plastic tank, this alternative is not prone to cracking, leaking, or weakening. With the Turner Motorsport Aluminum Intercooler Expansion Tank Kit, you'll never experience expansion tank failure again! Ideal for track-driven cars, this upgrade prevents catastrophic failures that cause charge-air temp spikes and limp mode due to coolant loss in a system with no level sensor. Unlike other aftermarket coolant reservoirs, this tank retains the factory coolant capacity and features a laser-cut Turner logo plate at the top of the tank to provide an exact level for filling. 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. Designed for both high-performance builds and daily drivers, the tank features a premium wrinkle black powder coat for a sleek "OEM+" look. This durable finish goes beyond style—it prevents corrosion for long-lasting reliability. Avoid the risks of the factory expansion tank—upgrade your S55-equipped BMW today and drive with confidence!
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Automatic Transmission Thermostat Kit
10X Entries Into Our F80 M3 Sweepstakes
Packaged by Turner - Corporate Logo
T#:57122955
Part#: 17111438819KT2
Ships on Dec 30, 2026
New Item
$ 93.66 USD
Free Shipping on orders $49 and up
Keeping your E53 X5 automatic transmission cool is essential for longevity and peak performance. The factory transmission thermostat circuit relies on plastic housings and o-ring seals that deteriorate over time. When the transmission thermostat fails or it's mounting assembly cracks, coolant loss follows putting your transmission at risk of overheating under load.
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Coolant Expansion Tank
2X Entries Into Our F80 M3 Sweepstakes
URO - Corporate Logo
T#:55749607
Part#: 17132284600
In Stock
New Item
$ 168.99 USD
Free Shipping on orders $49 and up
This URO Coolant Expansion Tank is a budget-conscious alternative that's designed to handle the rigorous fluid expansion and pressure demands of your M car.

Mishimoto - Corporate Logo
T#:51039948
Part#: MMB-E36-001
Ships in 4 Business Days
New Item
$ 1,150.99 USD
$ 1,150.99 USD
Each part in this bundle is selected to improve the E36's fluid dynamics and thermal stability.

ECS - Corporate Logo
T#:56327169
Part#: 059178LA01
In Stock
New Item
Sale - Save 9% $ 407.99

This product was last offered at the strikethrough price on
07-23-2026

$ 369.99 USD
Free Shipping
Sale - Save 9%
$ 407.99

This product was last offered at the strikethrough price on
07-23-2026

$ 369.99 USD
Free Shipping

Gen 2 MINI R5X models (R55, R56, R57, R58, R59, R60, and R61 chassis) utilize a closed, highly pressurized cooling system to maintain optimal engine operating temperatures. At the center of this system is the factory plastic expansion tank, which is constantly exposed to high heat cycles, vibration, and chemical-laden antifreeze. Over time, heat and pressure leach the plasticizers from the original material. This degradation causes the tank to turn brittle and yellow, eventually leading to micro-fractures, splitting along the factory blow-molded center seam, or catastrophic connection failure. Because coolant loss under pressure can occur rapidly, a failing stock tank frequently leads to severe overheating issues or unexpected roadside breakdowns.

This ECS Heavy Duty Aluminum Coolant Expansion Tank directly addresses the structural vulnerabilities of the factory unit by replacing molded plastic with a fully TIG-welded 5052 and 6061 aluminum construction. Aluminum eliminates the risk of seam separation, cracking, or heat deformation, providing a permanent solution that withstands continuous pressure and heat without expanding or fatiguing. To ensure precise fitment, the tank was engineered using 3D CAD modeling for a direct, plug-and-play installation in the factory location. No cutting, drilling, or custom bracketry is required to secure the unit.

All hose barbs, bleed points, and sensor ports are CNC-machined to precise tolerances, guaranteeing a leak-free seal with factory quick-disconnect hoses. A precision-threaded cap neck ensures smooth engagement with the expansion tank cap while maintaining an airtight seal against the internal cap O-rings. To simplify routine maintenance, an integrated external sight glass and internal level tab eliminate guesswork, allowing you to check your coolant level at a glance. Finally, the heavy-duty wrinkle black powder coat protects the exterior of the tank from oxidation and engine bay heat while providing a clean, OEM+ appearance.

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URO Coolant Expansion Tank Cap - G2x G4x G6x G7x
2X Entries Into Our F80 M3 Sweepstakes
URO - Corporate Logo
T#:56760937
Part#: 17138665638
Ships in 2 Business Days
New Item
$ 25.99 USD
$ 25.99 USD
A compromised expansion tank cap can lead to loss of pressure, fluid leaks, and dangerous engine overheating. This URO Coolant Reservoir Cap provides a dependable, cost effective solution to restore factory pressure thresholds on modern G-Chassis BMW models.
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Rein Engine Coolant Reservoir - BMW G1X, G3X
2X Entries Into Our F80 M3 Sweepstakes
Rein - Corporate Logo
T#:52516268
Part#: EPT0274
Back Ordered
New Item
Sale - Save 5% $ 114.99

This product was last offered at the strikethrough price on
08-31-2026

$ 109.24 USD
Free Shipping on orders $49 and up
Sale - Save 5%
$ 114.99

This product was last offered at the strikethrough price on
08-31-2026

$ 109.24 USD
Free Shipping on orders $49 and up
Protect your BMW investment with the Rein EPT0274 Engine Coolant Reservoir, the professional’s choice for cooling system restoration.
Rein Coolant Expansion Tank - With Cap
2X Entries Into Our F80 M3 Sweepstakes
Rein - Corporate Logo
T#:53891623
Part#: 17135A6A030C
Ships in 4 Business Days
New Item
Sale - Save 6% $ 99.99

This product was last offered at the strikethrough price on
08-31-2026

$ 94.07 USD
Sale - Save 6%
$ 99.99

This product was last offered at the strikethrough price on
08-31-2026

$ 94.07 USD
Replace your old brittle expansion tank

Rein - Corporate Logo
T#:55965843
Part#: 171386106612
Ships in 4 Business Days
New Item
Sale - Save 5% $ 49.99

This product was last offered at the strikethrough price on
08-31-2026

$ 47.49 USD
Sale - Save 5%
$ 49.99

This product was last offered at the strikethrough price on
08-31-2026

$ 47.49 USD
Keep your ultimate driving machine cool under pressure with this replacement auxiliary expansion tank from Rein. On modern turbocharged BMWs, the secondary cooling system plays a critical role in managing intake charge air temperatures, making a solid reservoir vital for both spirited street driving and track day reliability.
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Rein - Corporate Logo
T#:55965839
Part#: 17138610661
Ships in 4 Business Days
New Item
Sale - Save 5% $ 56.99

This product was last offered at the strikethrough price on
08-31-2026

$ 54.14 USD
Free Shipping on orders $49 and up
Sale - Save 5%
$ 56.99

This product was last offered at the strikethrough price on
08-31-2026

$ 54.14 USD
Free Shipping on orders $49 and up
Keep your ultimate driving machine cool under pressure with this replacement auxiliary expansion tank from Rein. On modern turbocharged BMWs, the secondary cooling system plays a critical role in managing intake charge air temperatures, making a solid reservoir vital for both spirited street driving and track day reliability.
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Coolant Expansion Tank
2X Entries Into Our F80 M3 Sweepstakes
Rein - Corporate Logo
T#:57086700
Part#: 17137642158
Ships in 4 Business Days
New Item
Sale - Save 7% $ 55.99

This product was last offered at the strikethrough price on
08-31-2026

$ 52.35 USD
Sale - Save 7%
$ 55.99

This product was last offered at the strikethrough price on
08-31-2026

$ 52.35 USD
The factory expansion tank is one of the most common failure points in modern BMW cooling systems, often failing along seam welds or developing micro-cracks around fluid quick-connect fittings. Replacing a degraded reservoir with this direct-fit Rein expansion tank restores pressure containment, ensures accurate coolant expansion volume, and prevents fluid loss before it turns into severe engine damage.
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Vargas Turbo Technologies - Corporate Logo
T#:51848504
Part#: VTT-B58-CEBLUE
Ships in 10 Business Days
New Item
$ 59.99 USD
Free Shipping
$ 59.99 USD
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Elevate your BMW's engine bay while safeguarding your cooling system with the VTT B58 Expansion Tank Hose in Blue.


Vargas Turbo Technologies - Corporate Logo
T#:52164880
Part#: N54CLVTBLKO
Ships in 10 Business Days
New Item
$ 54.99 USD
Free Shipping
$ 54.99 USD
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The VTT N54 Upper Vent Hose is a critical upgrade for any BMW enthusiast looking to eliminate the weakest links in their cooling system.
Coolant Expansion Tank
5X Entries Into Our F80 M3 Sweepstakes
Meyle - Corporate Logo
T#:54959296
Part#: 314 223 0004
Ships on Sep 22, 2026
New Item
$ 75.99 USD
Free Shipping on orders $49 and up
This Meyle original-quality expansion tank provides a durable, reliable solution to get your cooling system back to performing exactly as it should.
Coolant Expansion Tank - With Cap
10X Entries Into Our F80 M3 Sweepstakes
Bremmen Parts - Corporate Logo
T#:55497428
Part#: 17137640514
Ships on Nov 6, 2026
New Item
$ 69.99 USD
$ 69.99 USD

Coolant Expansion Tank
10X Entries Into Our F80 M3 Sweepstakes
Bremmen Parts - Corporate Logo
T#:53044121
Part#: 17137601948
In Stock
New Item
Sale - Save 15% $ 72.99

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

$ 62.04 USD
Free Shipping on orders $49 and up
Sale - Save 15%
$ 72.99

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

$ 62.04 USD
Free Shipping on orders $49 and up

Febi - Corporate Logo
T#:56001934
Part#: 46221
Special Order: No Guaranteed ETA
New Item
$ 19.99 USD
Free Shipping on orders $49 and up
This Febi Bilstein coolant expansion tank cap is designed to maintain the exact 1.4 bar pressure required to maximize your coolant's boiling point.
Febi - Corporate Logo
T#:56544005
Part#: 17139846642
Special Order: No Guaranteed ETA
New Item
$ 83.99 USD
Free Shipping on orders $49 and up
Protect your modern BMW from catastrophic thermal overload with the Febi Bilstein coolant expansion tank.

Febi - Corporate Logo
T#:56507814
Part#: 17137642160
Special Order: No Guaranteed ETA
New Item
$ 62.99 USD
Free Shipping on orders $49 and up
This Febi Bilstein coolant expansion tank offers OEM quality, engineered to withstand aggressive driving, high thermal loads, and pressurized environments.
Febi - Corporate Logo
T#:56544003
Part#: 17138677649
Special Order: No Guaranteed ETA
New Item
$ 82.99 USD
Free Shipping on orders $49 and up
Prevent catastrophic track-day or daily-driving overheating with this OEM-spec replacement Coolant Expansion Tank by Febi Bilstein.

Febi - Corporate Logo
T#:56544004
Part#: 17135A6A030
Special Order: No Guaranteed ETA
New Item
$ 82.99 USD
Free Shipping on orders $49 and up
This Febi Bilstein coolant expansion tank delivers the strength and exact fitment needed to keep your BMW's cooling system locked down.

E30 Coolant Expansion Tank
10X Entries Into Our F80 M3 Sweepstakes
Bremmen Parts - Corporate Logo
T#:57507437
Part#: 17111712641
Ships on Jan 6, 2027
New Item
$ 49.99 USD
$ 49.99 USD
Coolant Expansion Tank
5X Entries Into Our F80 M3 Sweepstakes
Meyle - Corporate Logo
T#:55569540
Part#: 17137823626
Ships on Sep 21, 2026
New Item
$ 74.99 USD
Free Shipping on orders $49 and up