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

Clear BMW chassis

Please ensure your correct model is selected

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.
Sort By:

Rein - Corporate Logo
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
Free Shipping on orders $49 and up
$ 86.99

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

$ 75.99 USD
Limited Qty Sale
Free Shipping on orders $49 and up
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.
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
Rein - Corporate Logo
T#:45757470
Part#: 17125A022D6
Ships in 2 Business Days
$ 35.99 USD
Free Shipping on orders $49 and up
$ 35.99 USD
Free Shipping on orders $49 and up
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.