E46 M3 Aluminum Expansion Tank by Moroso

Prevent catastrophe by replacing your aged, fragile plastic tank with a high-quality, long-lasting aluminum tank

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Our E46 M3 Aluminum Expansion Tanks by Moroso completely solve the common problem with the factory plastic tanks that get brittle over time and fail. When this occurs, you dump a lot of coolant, and that can cause a whole list of problems.  

Most expansion tanks are as inconvenient as stock and can be costly if you aren't paying attention enough to avoid failure, which could likely result in loss of control due to the slick fluid you've dumped all over the ground. Beyond the usual mess, the E46 M3 is extra special; when the plastic tank fails, it's usually somewhat spectacular. The released pressure often takes out your hood - an impressively devastating feat.

Before it fails, replace your old plastic unit with this high-quality, durable aluminum piece from Moroso. The Moroso expansion tank for the E46 M3 is a premium, race-quality reservoir with a sight glass for easy fluid level inspection. The expansion tank drops in like an OE reservoir and includes a bracket for securing the windshield washer filler neck. Includes 2-bar reservoir cap.

To learn more about Moroso expansion caps and cooling system pressures, check out this video:

Note: Tank does not have a provision for OE level sensor - dash warning light must be turned off by shorting two wires going to the level sensor plug.

Made in USA

BMW Fitments:

E46 (99-05) > M3
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