Expansion Tank with Sensor and Cap for BMW E90

E90

$34.99

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Key Features

Replacement expansion tank for BMW E90 applications
Includes coolant level sensor and cap
Good fit for aging cracked original tanks
Best paired with a full cooling system inspection
Verify engine-specific fitment before ordering
Budget-friendly option at $34.99

Product Details

Category: Expansion Tanks
ASIN: B0C5LJPCV1

Check if it fits your BMW

Expansion Tank with Sensor and Cap for BMW E90 — Overview

This is a replacement coolant expansion tank for E90-era BMWs, sold with the level sensor and cap already included. On cars in this range, the tank is a known failure point once the plastic gets heat-cycled enough times, and when it goes, it usually does not give you much warning beyond a small seep or low coolant message. If your original tank is stained, cracked around the seams, or the sensor has gotten flaky, this is the straightforward fix.

I would pick this when you want to replace the whole assembly in one shot instead of reusing an old cap or questionable sensor. It makes the most sense on a driver-grade E90 where you are handling a cooling system refresh and want the wear items done together. Just make sure your exact model fitment lines up before ordering, because BMW used a few different tank setups depending on engine and production range.