Rein BMW Coolant Expansion Tanks for BMW 3 Series E46 (1999-2005)

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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 Coolant Expansion Tank - E46, E53, E83
2X Entries Into Our F80 M3 Sweepstakes
Rein - Corporate Logo
T#:402141
Part#: 17117573781
In Stock
$ 76.39 USD
Free Shipping
$ 76.39 USD
Free Shipping
Includes cap and level sensor
Expansion Tank Mounting Plate
2X Entries Into Our F80 M3 Sweepstakes
Rein - Corporate Logo
T#:402140
Part#: 17111436250
In Stock
$ 70.99 USD
Free Shipping
$ 70.99 USD
Free Shipping
Rein Expansion Tank Mounting Plate - E46, Z4
For vehicles with automatic transmission only
2X Entries Into Our F80 M3 Sweepstakes
Rein - Corporate Logo
T#:402139
Part#: 17111436251
Ships in 2 Business Days
$ 80.99 USD
Free Shipping
$ 80.99 USD
Free Shipping
Mounts to the side of the radiator for retaining the expansion tank

Rein - Corporate Logo
T#:340541
Part#: 17111742231
Ships in 2 Business Days
$ 17.99 USD
Free Shipping on orders $49 and up
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.
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