Mercedes-Benz S-Class W221 Brake Booster Servo Master Cylinder A2214304230

Mercedes-Benz S-Class W221 Brake Booster Servo Master Cylinder is a key component of the braking system, responsible for the stable transfer of force from the brake pedal to the hydraulic system. The offered servo integrated with the master brake cylinder has been designed specifically for the W221 generation S-Class, ensuring precise pressure dosing and predictable vehicle response during braking. Using an OEM component allows you to maintain the factory braking characteristics while keeping repair costs favorable.

Specifications and technical data

• SKU: A2214304230
• Mark: Mercedes (Genuine OE)
• Condition: Used
• OEM Part Number: A2214304230
• Substitutable numbers: A2214304230, A 221 430 42 30, A2214304330, A 221 430 43 30, A2214300601, A 221 430 06 01, A2214300002, A 221 430 00 02, KZ
• Category: Brake Servos

Purpose and function in the braking system

The brake servo integrated with the master cylinder in the Mercedes S-Class W221 is responsible for amplifying the pressure force on the pedal and stably supplying the brake circuits with fluid at the appropriate pressure. A properly selected component from this group guarantees:

• consistent, repeatable brake pedal feel throughout the entire operating range,
• proper assistance during emergency braking,
• maintenance of the factory operating characteristics of safety systems, such as ABS or ESP.

Thanks to a design compliant with the vehicle manufacturer's requirements, the servo with the master cylinder works with the factory electronics and hydraulics of the braking system, which reduces the risk of compatibility issues.

Technical category: Brake servos and force regulators

The presented element belongs to the Brake servos and force regulators group, i.e., components responsible for assistance and the appropriate distribution of braking force between the axles. In practice, this means that this element:

• influences vehicle stability during intensive braking,
• enables precise control of pressure in the brake circuits,
• supports the operation of brake force correction systems under various vehicle load conditions.

For a luxury limousine such as the Mercedes S-Class W221, a properly functioning servo with a master cylinder has a direct impact on driving comfort and safety, especially at higher highway speeds.

Benefits of using an original used component

Choosing a used, original component from this group is a solution that allows you to combine factory fitment for the braking system with rational service costs. Compared to low-quality replacements, the original servo with master cylinder provides:

• preservation of the brake pedal operating characteristics designed by the manufacturer,
• better compatibility with factory lines, mounts, and accessories,
• lower risk of bleeding and system tightness issues.

A used element of this class, sourced from dismantling, is particularly attractive for repairs of advanced models where new OEM parts are expensive or difficult to obtain.

Professional installation and operation

To fully utilize the potential of the offered servo with master cylinder, installation in a specialized service center is recommended, which will ensure:

• proper connection to the vacuum system and brake lines,
• thorough bleeding of the entire system,
• verification of tightness and correct brake pedal operation after installation.

During operation, it is worth regularly checking the condition of the brake fluid and reacting to any changes in pedal operation, such as excessive "sponginess" or increased braking distance. This will allow you to maintain stable and predictable braking system operation in the long term.

Mercedes brake servos and force regulators – expansion and part selection

If you are planning a comprehensive repair or upgrade of the braking zone in your Mercedes and need other elements from the same group, such as additional servos, brake force regulators, or related assistance modules, check the available parts in the Mercedes brake servos and force regulators category.

How to care for used braking system components

When using a used servo with a master cylinder, it is worth paying attention to the proper operation of the entire braking system – regular fluid replacement, inspection of flexible and rigid lines, and the condition of the calipers. Practical tips on maintenance and extending the durability of dismantled components can be found in the article How to extend the service life of used car parts?, which describes proven methods for using and servicing such subassemblies.