Engine Coolant Reservoir Radiator Expansion Tank Compatible With BMW

In this review of the Engine Coolant Reservoir Radiator Expansion Tank compatible with BMW E90 E91 E92 E93 models, the bottom line is straightforward: it is a budget-friendly replacement aimed at DIY owners and independent shops who need a direct-fit coolant tank with cap and level sensor. The reviewer found the part to be a practical OEM-style swap for many 2006-2016 BMW 1, 3, X1 and Z4 variants, with the biggest reason to buy being the complete package that includes the tank, cap and sensor for a single installation.

Key Features

• Complete Replacement: Ships with the coolant reservoir, cap and level sensor so installers do not need to source parts separately.
• Wide Vehicle Fitment: Designed to fit a broad list of BMW models from 2006 to 2016, including E90/E91/E92/E93 328i and 335i variants.
• OEM-Compatible Numbers: Replaces multiple factory part numbers so it is easy to confirm compatibility with the vehicle's existing tank.
• Durable Construction: Molded from plastic materials that match OEM durability expectations for a long service life when installed correctly.
• DIY-Friendly: Straightforward installation saves shop time and lets owners replace the tank themselves to reduce repair cost.

Who It's For

This coolant reservoir is best for BMW owners and independent mechanics who need a direct replacement for damaged or leaking expansion tanks on 1 Series, 3 Series and related models from 2006 through 2016. It suits those who prefer to replace the entire assembly including the cap and sensor in one job rather than hunting individual parts.

It is less well suited to owners who require OEM branding for warranty reasons or those with vehicles outside the listed fitment. Also, if a user needs reassurance about long-term leak performance, a dealer OEM unit might offer more documented history.

Pros & Cons

Pros

• Complete kit including tank, cap and level sensor reduces installation steps.
• Good fit for many BMW E90/E91/E92/E93 and related models, so compatibility checks are straightforward.
• Customers report ease of installation and satisfactory functionality once installed.

Cons

• Some buyers reported occasional leakage or missing cap issues, so inspect the unit on arrival.
• Not an OEM-branded item, which may concern buyers wanting factory-sourced parts.

Specifications

Brand	Dtomi
Included Parts	Coolant reservoir tank, cap, level sensor
Replacement Part Numbers	603-334, 17137640514, 17137567462 and others
Other Part Numbers	376789751, EPT0028
Fitment Years	2006-2016 (varies by model)
Compatible Models	BMW 1 Series, 3 Series, X1, Z4 (select years and engines)

Our Verdict

The Dtomi coolant reservoir assembly is a sensible value choice for DIYers and independent shops that need a full replacement tank, cap and sensor for BMW E90/E91/E92/E93 and related models. It delivers good fit and functional performance when inspected before installation, but buyers should check the part on arrival for cap presence and signs of leakage to avoid installation issues.

Frequently Asked Questions

Does this include the cap and sensor?
Yes, the package includes the coolant reservoir, cap and level sensor so the assembly is ready for installation.

Will this fit my 328i or 335i from 2007?
It is listed as compatible with 2007-2013 328i and 2007-2010 335i variants; confirm the part numbers against your vehicle before ordering.

What if the part leaks or the cap is missing?
Some customers have reported leakage or missing cap issues; inspect the item on delivery and contact the seller for resolution if a problem is found.