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BMW Coolant Expansion Tanks

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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Automatic Transmission Thermostat Kit
10X Entries Into Our F80 M3 Sweepstakes
Packaged by Turner - Corporate Logo
T#:57122955
Part#: 17111438819KT2
Ships on Dec 30, 2026
New Item
$ 93.66 USD
Free Shipping on orders $49 and up
Keeping your E53 X5 automatic transmission cool is essential for longevity and peak performance. The factory transmission thermostat circuit relies on plastic housings and o-ring seals that deteriorate over time. When the transmission thermostat fails or it's mounting assembly cracks, coolant loss follows putting your transmission at risk of overheating under load.
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