BMW X3 E83 E83N LCI Bracket Expansion Tank Bracket Support Mount 3403987

BMW X3 E83 E83N LCI Bracket Expansion Tank Bracket Support Mount is an original component from the Expansion tanks group, designed for stable mounting of the reservoir in the engine bay. This used OEM part ensures a factory fit, proper support, and secure positioning of the reservoir, which translates into reliable operation of the cooling system in the BMW X3 E83.

Specifications and technical data

• SKU: 3403987
• Mark: BMW (Genuine OE)
• Condition: Used
• OEM Part Number: 3403987
• Substitutable numbers: 3403987, 17133403987
• Category: Expansion & Overflow Tanks

Purpose and function of the bracket

The expansion tank bracket in the BMW X3 E83 is responsible for a secure, rigid attachment of the reservoir in its designated place, ensuring it does not transmit excessive vibrations or shift position while driving. A correctly selected mounting component reduces the risk of cracked connectors, hose leaks, and uncontrolled stress within the cooling system.

The original bracket from this reference was designed specifically for the geometry of the BMW X3 E83 engine bay, ensuring the correct distance from adjacent components and the proper position of the reservoir relative to hoses and mounting points.

Benefits of using an original BMW component

Using a factory bracket instead of a damaged or makeshift repaired part helps restore the original rigidity and stability of the system. In practice, this means:

• better support for the expansion tank in both road and off-road conditions,
• reduction of vibrations transmitted to connectors and hoses,
• preservation of the cooling hose routing geometry designed by the manufacturer,
• easier service access to the reservoir and adjacent components.

As a result, the cooling system operates under stable conditions, and the risk of failure resulting from improper reservoir support is significantly reduced.

Characteristics of the used bracket

The offered bracket comes from disassembly and is classified as a used BMW part. This type of component, while maintaining correct geometry and mounting points, retains full installation functionality, providing an economical solution compared to a new OEM part. A used element allows for maintaining the structural integrity of the engine bay without the need for aftermarket replacements with uncertain fitment.

Choosing an original, used bracket is particularly beneficial for post-accident repairs, replacing damaged plastic mounts, or restoring the factory configuration after previous mounting modifications.

Selection and compatibility within the cooling system

The bracket has been designed to work with the factory expansion tank used in the BMW X3 E83. Consequently, there is no need for interference with the bodywork or additional mounting elements – the brackets, clips, and mounting points are consistent with the vehicle's original design. This solution reduces the time required for installation and minimizes the risk of improper reservoir seating.

When selecting the part, it is worth paying attention to compatibility with the cooling system of the specific X3 E83 engine version to ensure full compatibility with the existing reservoir and hoses. The original bracket from this series was developed specifically with such fitment in mind.

System expansion – BMW Expansion tanks

If you are planning a comprehensive repair or upgrade of the engine area in your BMW and need other components from the same group, such as additional reservoirs, caps, or related brackets, check out the available parts in the BMW Expansion tanks category.

Support for sourcing used parts

For major repairs, it is often necessary to simultaneously select several mounting elements, hoses, and cooling system accessories. To plan your purchases more efficiently and avoid accidentally combining incompatible replacements, it is worth using practical tips on sourcing used components. More information can be found in the article Comprehensive supply: from the engine to the smallest clip – how to source used car parts in one place?, which discusses the advantages of a One-Stop-Shop approach and the importance of selecting original used parts.