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Bavarian Autosport 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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Bav Auto Coolant Expansion Tank - E36 E39 Z3 M50 M52 S50 S52 ...

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T#:638094

Part#: 17111723520

In Stock

Sale - Save 20% $ 39.99

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

$ 31.99 USD

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$ 39.99

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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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Bav Auto Coolant Expansion Tank - E53 X5, E46, E83 X3

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T#:640496

Part#: 17137787039

In Stock

Sale - Save 18% $ 61.99

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

$ 50.99 USD

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Sale - Save 18%

$ 61.99

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

$ 50.99 USD

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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

In Stock

Sale - Save 20% $ 44.99

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

$ 35.99 USD

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Sale - Save 20%

$ 44.99

This product was last offered at the strikethrough price on
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$ 35.99 USD

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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

In Stock

Sale - Save 20% $ 98.99

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

$ 79.19 USD

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$ 79.19 USD

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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

In Stock

Sale - Save 20% $ 45.99

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

$ 36.79 USD

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$ 45.99

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

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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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T#:640493

Part#: 17138570079

In Stock

Sale - Save 20% $ 78.99

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

$ 63.19 USD

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Sale - Save 20%

$ 78.99

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

$ 63.19 USD

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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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Bav Auto Coolant Expansion Tank - With Level Sensor - E70 X5, E71 X6 ...

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T#:638093

Part#: 17138621092

In Stock

Sale - Save 20% $ 60.99

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

$ 48.79 USD

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Sale - Save 20%

$ 60.99

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

$ 48.79 USD

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Replace your old expansion tank to prevent potential failure or leaks. Includes a brand new coolant level sensor.

Bav Auto Expansion Tank Cap - E36 E46 E34 E39 E32 E38 E65 X3 X5 Z4 ...

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T#:640208

Part#: 17117639022

In Stock

Sale - Save 15% $ 13.99

This product was last offered at the strikethrough price on
06-03-2026

$ 11.89 USD

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$ 13.99

This product was last offered at the strikethrough price on
06-03-2026

$ 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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Bav Auto Coolant Level Sensor - BMW E36 E39 M50/52 S50/52

affirm Starting At 0% APR - Subject To Eligibility. See Lending Terms

T#:639793

Part#: 61318360855

In Stock

Sale - Save 19% $ 20.99

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

$ 16.99 USD

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Sale - Save 19%

$ 20.99

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

$ 16.99 USD

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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 - E60 E61 E63 E64 M54 N52 N62 ...

affirm Starting At 0% APR - Subject To Eligibility. See Lending Terms

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

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Sale - Save 10%

$ 54.99

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

$ 49.49 USD

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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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Bavarian Autosport BMW Coolant Expansion Tanks

Bav Auto Coolant Expansion Tank - E36 E39 Z3 M50 M52 S50 S52 ...

Bav Auto Coolant Expansion Tank - E53 X5, E46, E83 X3

Bav Auto Expansion Tank Mounting Plate - E46 Non-M w/ Manual Trans ...

BMW N47 N55 Expansion Tank

Bav Auto Expansion Tank Mounting Plate - E46 Non-M w/ Auto Trans ...

Bav Auto Coolant Expansion Tank - BMW E90 335d M57 3.0L

Bav Auto Coolant Expansion Tank - With Level Sensor - E70 X5, E71 X6 ...

Bav Auto Expansion Tank Cap - E36 E46 E34 E39 E32 E38 E65 X3 X5 Z4 ...

Bav Auto Coolant Level Sensor - BMW E36 E39 M50/52 S50/52

Bav Auto Coolant Expansion Tank - E60 E61 E63 E64 M54 N52 N62 ...

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