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BMW Coolant Expansion Tanks for BMW Z4 M Roadster S54 (2003-2008)

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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Genuine BMW Expansion Tank Cap - E3X / E53 / Z4

T#:207187

Part#: 17117639022

In Stock

21% off MSRP $ 34.96

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

$ 27.67 USD

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21% off MSRP

$ 34.96

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

$ 27.67 USD

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Genuine BMW Radiator Cap - 2,0Bar
This item fits the following BMW Chassis:
E36 M3,E39 M5,E46 M3,E85 Z4M,E53 48IS,E36,E38,E39,E46,E53 X5,E65,E83 X3,E85 Z4,E86 Z4,F06,F10,F12,F13

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Genuine BMW Expansion Tank - E85 Z4 M Coupe/Roadster S54

T#:22487

Part#: 17107836448

Back Ordered

5% off MSRP $ 215.99

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

$ 205.99 USD

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5% off MSRP

$ 215.99

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

$ 205.99 USD

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Genuine BMW Expansion Tank
This item fits the following BMW Chassis:
E85 Z4M,E85 Z4,E86 Z4

Fits BMW Engines including:
S54

OEM Rein Expansion Tank Cap - BMW E32 E34 E36 E38 E39 E46 & More ...

2X Entries For Our G87 M2 Sweepstakes! We Price Match - Give Us A Call or Chat!

T#:340541

Part#: 17111742231

In Stock

$ 17.99 USD

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$ 17.99 USD

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

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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Qty

Sale - Save 15%

$ 13.99

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

$ 11.89 USD

Add to Wish List

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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BMW Coolant Expansion Tanks for BMW Z4 M Roadster S54 (2003-2008)

Genuine BMW Expansion Tank Cap - E3X / E53 / Z4

Genuine BMW Expansion Tank - E85 Z4 M Coupe/Roadster S54

OEM Rein Expansion Tank Cap - BMW E32 E34 E36 E38 E39 E46 & More ...

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

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