BMW F20 F21 F22 F30 F31 F32 M Sport Brake Servo Unit Master Cylinder 6798425

BMW M Sport Brake Booster with Master Cylinder for the F20, F21, F22, F30, F31, and F32 series is an original brake system component designed for high-performance versions. This OEM solution ensures stable braking assistance, precise force modulation at the pedal, and compatibility with the factory BMW brake system configuration.

Specifications and technical data

• SKU: rhd-6851096
• Mark: BMW (Genuine OE)
• Condition: Used
• OEM Part Number: 6798425
• Substitutable numbers: 34336851096 34336851098 34337851569, 6798425, 6851096 6851098 7851569, 34336796531 34337852160, 6796531 7852160, ŁS
• Category: Brake Servos

Intended Use and Compatibility with BMW F Series

The offered brake booster integrated with the master cylinder has been designed for BMW F series models equipped with the M Sport package, such as the F20/F21 (compact), F22 (coupe), and F30/F31/F32 (mid-size segment). The construction adheres to the manufacturer's factory specifications, ensuring the component works seamlessly with the original ABS/DSC system and factory brake calipers and discs.

As part of the brake boosters and force regulators group, this component is responsible for the correct transfer of force from the brake pedal to hydraulic pressure in the circuits, which is crucial for braking effectiveness in sporty vehicles.

Construction and Technical Characteristics

The M Sport brake booster utilizes vacuum assistance, which reduces driver effort while maintaining a clear, predictable brake engagement point. The integrated master cylinder distributes pressure to the front and rear axle circuits, ensuring stable system operation under various road conditions.

The OEM BMW solution means:

• maintaining the factory brake pedal characteristics,
• correct interaction with the vehicle's electronics,
• appropriate rigidity and resistance to dynamic loads,
• compatibility with factory brake lines and mounting points.

As a result, the booster with master cylinder provides a safe foundation for maintaining original braking effectiveness in M Sport equipped vehicles, without the need for structural modifications.

Application in Service and Upgrades

This component is suitable both as a replacement part for brake system repairs and for restoring full functionality to vehicles after collisions or intensive track use. Choosing an original BMW OE component minimizes the risk of compatibility issues that can arise with aftermarket alternatives having different operating characteristics.

In workshop practice, a brake booster with a master cylinder of this type is particularly useful when:

• the brake pedal becomes too soft or has a non-linear characteristic,
• there are problems maintaining constant pressure in the system,
• the complete booster and master cylinder assembly needs replacement.

For users who are also servicing other vehicle systems, tips from the article on selecting and maintaining used OEM components in comfort systems may be useful, as it describes best practices for working with original parts.

Benefits of Choosing an Original BMW OE Brake Booster

Using an original M Sport version brake booster with master cylinder offers a range of practical benefits:

• Factory Fitment – maintaining the original geometry, mounting points, and operating parameters of the brake system.
• Compatibility with Safety Systems – correct interaction with ABS, traction control, and stability control, without the need for software adaptation.
• Predictable Vehicle Behavior – consistent braking performance, essential for dynamic driving and in higher-powered vehicles.
• Professional Service Solution – a part designed for direct installation in place of the factory assembly, simplifying the mechanic's work.

Condition, Origin, and Compatibility Verification

The offered component comes from the BMW OE line, meaning it is a part from the same group of components that the manufacturer uses for initial assembly. The product is used, which in workshop practice allows for economical restoration of brake system functionality while maintaining original specifications.

Before purchasing, it is advisable to compare the markings and type of the installed brake booster with master cylinder in your vehicle, using catalog data or reference numbers in the specifications tab. This will help you select a compatible brake booster and force regulator assembly that will work with your existing brake system configuration in your BMW F Series.