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BMW Coolant Expansion Tanks for BMW 3 Series F34 (2014+)

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 Coolant Expansion Tanks Kit - F22/23 F3X B48 B58

10X Entries Into Our F80 M3 Sweepstakes

T#:27605427

Part#: 17138677649TKT

Ships in 2 Business Days

Sale - Save 3% $ 208.99

This product was last offered at the strikethrough price on
05-03-2026

$ 202.62 USD

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Sale - Save 3%

$ 208.99

This product was last offered at the strikethrough price on
05-03-2026

$ 202.62 USD

Add to Wish List

Genuine BMW expansion tanks have a bad habit of failing after a few years. This has primarily been caused by the plastic construction of the expansion tanks. After enough heat cycles, the plastic becomes brittle and can crack, causing coolant to leak out and air to enter the coolant system. If a failing expansion tank is not addressed soon enough, the coolant loss can lead to an overheating engine. This kit includes two brand new high quality expansion tanks and caps

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MTC Charge Air Cooler Expansion Tank - BMW F22/23 F3X B48/B46 B58 ...

T#:27405534

Part#: 17138617045

Ships in 9 Business Days

$ 64.46 USD

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$ 64.46 USD

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Your charge air cooler's coolant expansion tank acts as a reservoir, housing extra coolant, and gives fluid a place to go after expansion and contraction from temperature change. Because the plastic tank is subjected to regular temperature changes, the plastic can become brittle over time and will often crack or break. If your tank is leaking and you lose too much coolant, your charge air cooler will not function properly and your air intake temperatures will begin to rise, reducing horsepower and efficiency. If your tank has experienced damage such as cracking, nipples breaking off, or mounting point damage, you will need to replace it.

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