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Rein BMW Coolant Expansion Tanks for BMW G01 X3 xDrive30i B46 2.0L

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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OEM Rein Coolant Expansion Tank Overflow Hose - BMW G01 G02 Gen1 B46/...

For early models with the Gen1 B46/B48 engine - Not for vehicles with the later TU engines

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T#:45757470

Part#: 17125A022D6

Back Ordered

$ 35.99 USD

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$ 35.99 USD

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This hose connects the expansion tank to the radiator. If your coolant expansion tank hose is cracked or leaking, replace it early to prevent further coolant loss and eventual overheating.

OEM Rein Coolant Expansion Tank - F97 F98 G01 G02 B46 B58 S58 ...

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

T#:39059266

Part#: 17135A6A030

In Stock

$ 86.99

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

$ 75.99 USD

Limited Qty Sale

Add to Wish List

Qty

$ 86.99

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

$ 75.99 USD

Limited Qty Sale

Add to Wish List

Coolant expansion tanks can crack over time, especially during services where they need to be removed. Replace your tank with a brand new tank to ensure your cooling system remains leak-free.