Rein BMW Coolant Expansion Tanks for BMW 3 Series E90 (2006-2011)

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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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Rein Expansion Tank Cap
2X Entries Into Our F80 M3 Sweepstakes
Rein - Corporate Logo
T#:384807
Part#: 17117639021
In Stock
$ 16.99 USD
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Cap for plastic expansion tank
BMW Expansion Tank With Cap - 17138570079
2X Entries Into Our F80 M3 Sweepstakes
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T#:46616019
Part#: EPK0146
Ships in 3 Business Days
$ 93.99 USD
Free Shipping on orders $49 and up
The coolant expansion tank serves as a reservoir for excess coolant as it expands and contracts with changing temperatures. Since it’s constantly exposed to extreme heat cycles, it can eventually crack, split, or suffer broken nipples or mounting points. To keep your cooling system sealed and operating properly, any damaged tank should be replaced.
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BMW Coolant Expansion Tank With Cap
2X Entries Into Our F80 M3 Sweepstakes
Rein - Corporate Logo
T#:46616007
Part#: EPK0131
Back Ordered
$ 104.99 USD
Free Shipping on orders $49 and up
The coolant expansion tank provides a place for excess coolant to flow as temperatures rise and fall. Because it constantly endures extreme temperature changes, it’s prone to cracking or breaking over time. Keeping coolant contained within the system is essential, so if your tank shows signs of damage—such as cracks, broken nipples, or compromised mounting points—it’s time for a replacement.
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