Mercedes W177 W247 Brake Servo Booster Master Cylinder Braking Unit A2474300100

Brake Booster (Brake Servo with Master Cylinder) Mercedes W177 / W247 is an original brake system component designed for the latest generation A-Class and B-Class models. As part of the Brake Servos and Force Correctors group, it ensures stable transfer of pedal pressure to system pressure, resulting in predictable and safe braking performance. A used OEM component is a sensible choice for professional repairs when you prioritize factory performance characteristics and a perfect fit for the specific Mercedes platform.

Specifications and technical data

• SKU: rhd-A2474300100
• Mark: Mercedes (Genuine OE)
• Condition: Used
• OEM Part Number: A2474300100
• Substitutable numbers: A2474300100, A 247 430 01 00, A1774305600, A 177 430 56 00, A1774304400, A 177 430 44 00, BG
• Category: Brake Servos

Purpose and Function in the Braking System

The presented brake servo unit with master cylinder is a key element of the hydraulic braking system in Mercedes A-Class (W177) and B-Class (W247) models. It is responsible for:

• assisting brake pedal force by utilizing vacuum,
• precise metering of pressure in the brake lines,
• maintaining consistent braking characteristics under various vehicle loads,
• interfacing with electronic safety systems such as ABS and ESP.

Thanks to its OEM design, correct geometry, piston stroke, and operating parameters are maintained, which directly impacts braking comfort and predictability in daily use.

Benefits of Using an Original Mercedes Brake Booster

Choosing an original brake booster with master cylinder for the Mercedes A/B-Class offers a range of practical advantages:

• Factory Fitment – a component designed specifically for the W177 / W247 platform, requiring no modifications or adaptations.
• Consistent Brake Pedal Feel – maintaining the same brake "feel" as in the factory configuration.
• Full compatibility with the hydraulic system and electronic brake assist systems.
• Ability to utilize existing mounting points and connections, facilitating installation in service conditions.
• Sensible cost-to-quality ratio due to the use of a proven, used OEM part.

Installation Characteristics and Service Application

The brake servo integrated with the master cylinder in this configuration is designed for direct installation in the engine bay of the relevant Mercedes models. In service practice, it is primarily used in situations where:

• a noticeable hardening of the brake pedal or lack of assistance is felt,
• leaks are present within the servo or master cylinder,
• the braking system requires comprehensive refurbishment after a collision or prolonged use.

By maintaining the original design, it is possible to restore the full functionality of the braking system without altering its factory parameters. This solution is particularly valued in workshops specializing in the Mercedes brand, where repair result consistency is crucial.

Component Condition and Operational Aspects

The offered unit comes from the group of used original Mercedes parts, meaning it retains the factory construction and operating characteristics intended by the manufacturer. In practice, this allows for:

• maintaining a high level of braking safety at a reasonable repair cost,
• compliance with service documentation and manufacturer procedures,
• easier future diagnostics due to the use of an OEM component.

Prior to installation, the standard service procedure is recommended: system leak check, brake fluid replacement, and thorough bleeding to fully utilize the potential of the installed brake servo and master cylinder.

If you are planning a comprehensive repair or upgrade of the braking area in your Mercedes and require other components from the same group, such as master cylinders, vacuum boosters, or brake force correctors, check the available parts in the Mercedes Brake Servos and Force Correctors category.

Technical Support and Selection of Used Components

When selecting used OEM components for safety systems like brakes, it is advisable to follow proven service procedures and technical knowledge. Topics related to component selection, maintenance schedules, and the impact of individual components on driving comfort and safety are discussed in more detail in the guide Air Conditioning and Heating – Part Selection and Maintenance for Year-Round Comfort, which helps to organize the approach to operating used OEM parts in modern vehicles.