VW Volkswagen Phaeton 3D Additional Expansion Reservoir Tank Bottle 3D2122407A

VW Volkswagen Phaeton 3D Additional Expansion Reservoir Tank Bottle is an original cooling system component designed for the luxury 3D generation Phaeton sedan. This used, factory-made component from the Expansion tanks group allows for maintaining stable engine operating parameters, ensuring an adequate coolant reserve and safe discharge of excess pressure.

Specifications and technical data

• SKU: RHD-3D2122407A
• Mark: Volkswagen
• Condition: Used
• OEM Part Number: 3D2122407A
• Substitutable numbers: 3D2122407A, 3D2 122 407 A
• Category: Expansion & Overflow Tanks

Purpose and function in the cooling system

The additional expansion reservoir in the Volkswagen Phaeton plays a key role in stabilizing the pressure and volume of coolant during engine operation. It is responsible for:

• compensating for changes in fluid volume as the engine heats up and cools down,
• safely collecting excess fluid from the main circuit,
• maintaining the proper fluid level in the system under various load conditions,
• reducing the risk of overheating and local air pockets.

The original design, tailored to the Phaeton 3D, guarantees proper hose connection and correct operation of the entire cooling system without the need for modifications.

Original Volkswagen part – fitment and compatibility

The presented expansion reservoir comes from the Volkswagen line, which means maintaining factory quality and geometry standards. Thanks to this:

• it fits the factory mounts in the Phaeton 3D engine bay,
• it ensures compatibility with original connectors and hose diameters,
• it maintains the operating capacity intended by the manufacturer,
• it does not require installation adaptations or additional mounting hardware.

Choosing an original expansion reservoir is a solution that facilitates service, reduces the risk of leaks, and supports the long-term, stable operation of the cooling system.

Characteristics of the used expansion reservoir

As a used item, the reservoir represents an attractive cost alternative to new parts while maintaining the factory design. It is a good solution in situations where:

• the existing reservoir has cracked or deformed,
• there are coolant leaks in the vicinity of the reservoir,
• it is necessary to replace the component after a collision or bodywork intervention,
• you are planning a preventive replacement of cooling system components in an older Phaeton model.

By using an original, used expansion reservoir, you maintain compliance with the manufacturer's design while optimizing repair or upgrade costs.

Benefits of using an original expansion reservoir

Using a factory expansion reservoir in a Volkswagen Phaeton translates into a number of practical benefits:

• Stable cooling system operation – properly selected capacity and reservoir geometry support the maintenance of correct pressure and fluid levels.
• Hassle-free installation – original mounts and connectors allow for efficient replacement in workshop conditions.
• Consistency with other components – maintaining the factory cooling system configuration facilitates further diagnostics and service.
• Reasonable operating cost – a used OEM component allows for lower repair costs without sacrificing the fitment intended by the manufacturer.

Related Volkswagen expansion reservoirs and technical materials

If you are planning a comprehensive repair or upgrade of the cooling system area in your Volkswagen and need other elements from the same group, such as additional expansion bottles, auxiliary fluid reservoirs, or cooling system reserve components, check the available parts in the Volkswagen expansion reservoirs category.

For users interested in a broader look at the construction of VW models and the selection of used parts in modernization projects, the article describing the development of sporty Golf versions may be helpful – Hot-hatch legend: the evolution of the VW Golf GTI from Mk1 to Mk8 – design changes and VW car parts, which discusses, among other things, areas where the use of original components is of the greatest importance for the durability and characteristics of the car.