Audi A4 B8 Brake Servo Booster Master Cylinder Braking Unit 1K2614105BN

Visual condition of the part

The product shows signs of use visible in the photos.

Audi A4 B8 Brake Servo Booster Master Cylinder Braking Unit is a complete braking system unit designed for the B8 generation Audi A4 models. The set combines the brake servo and the master cylinder, ensuring stable system pressure and predictable brake pedal response. It is a practical solution for users looking for a consistent, factory-spec component instead of replacing individual parts.

Specifications and technical data

• SKU: RHD-1K2614105BN-1
• Mark: Audi
• Condition: Used
• OEM Part Number: 1K2614105BN
• Substitutable numbers: 1K2614105BN, 1K2 614 105 BN, 252078499809
• Category: Master Cylinders

Purpose and function in the braking system

The described braking unit plays a key role in generating and boosting operating pressure in the Audi's braking system. The servo uses engine vacuum to increase the force applied to the master cylinder, providing the driver with a noticeably lighter yet precise pedal feel. Integrating both components into a single unit reduces the risk of leaks at connection points and simplifies the diagnostics of the entire system.

Construction of the brake servo–master cylinder unit

The unit consists of a brake servo housing and a master cylinder attached to it, forming a compact, easy-to-install module. This design:

• ensures stable force transmission from the brake pedal to the hydraulic system,
• reduces the number of connections and potential leak points,
• facilitates maintenance – removal and installation are performed as a single unit.

Thanks to the use of factory Audi solutions, the unit maintains the correct pedal operating characteristics, consistent with the vehicle manufacturer's specifications, which translates into predictable vehicle behavior during braking.

Benefits of using an original braking unit

Choosing a complete brake servo–master cylinder unit from Audi allows you to maintain the factory characteristics of the braking system without the need for aftermarket adaptations. The main advantages of this solution include:

• proper fitment to the engine bay geometry and mounting points in the Audi A4 B8,
• maintaining the correct piston length and travel relative to the brake pedal,
• seamless cooperation with other components of the vehicle's braking system.

The product belongs to the Brake master cylinders group, which means it is designed to operate under high pressure and in the variable operating conditions typical of intensive vehicle use.

Condition, selection, and compatibility verification

The item comes from our range of used Audi components, which allows for economical repair while maintaining the original design. Before installation, it is recommended to perform a standard check of the braking system for leaks, the condition of the lines, and proper bleeding to fully utilize the unit's capabilities.

To select the appropriate unit for a specific engine version and model year of the Audi A4 B8, it is worth using the OEM number and the interchangeable numbers visible in the specification section. In practice, this minimizes the risk of purchasing an incompatible part and speeds up the installation process.

Additional tips on safely selecting parts by manufacturer numbers and verifying compatibility can be found in our guide on purchasing parts online using OEM numbers, which describes proven methods for reducing errors when ordering components.

Audi braking zone – expansion of upgrades

If you are planning a comprehensive repair or upgrade of the braking zone in your Audi and need other elements from the same group, such as master cylinders, servos, or complete braking units, check out the available parts in the Audi Brake master cylinders category.

Technical support and additional knowledge

Although the described unit concerns the braking system, the principles of selection and diagnostics of components largely overlap with other vehicle systems. In the context of working with OEM numbers, interpreting manufacturer markings, and general service strategy, the article on the fuel system – injectors, pumps, and fuel tank – may be useful. A detailed discussion of diagnostics, regeneration, and part selection can be found in the entry "Fuel system – injectors, pumps, and fuel tank: maintenance and regeneration", which helps organize the approach to working with advanced vehicle systems.

Summary

Audi A4 B8 – brake servo unit with master cylinder is a practical solution for users who want to restore the proper operation of the braking system while maintaining factory performance characteristics. The complete design facilitates installation, and the use of an original Audi component promotes stable, predictable brake operation in daily use.