Brake Servo
- Porsche Boxster 986 2.5L 1997-99
- Porsche Boxster 986 2.7L 1999-02
- Porsche Boxster S 986 3.2L 1999-02
- Porsche Boxster 986 2.7L 2003-04
- Porsche Boxster S 986 3.2L 2003-04
- Porsche Boxster 987 2.7L 2005 -08/08
- Porsche Boxster 987 S 3.2/3.4L 2005-08/08
- Porsche Boxster 987 MKII 2.9L 2009-2012
- Porsche Boxster S 987 MKII 3.4L 2009-2012
- Porsche 996 C2 3.4L 1997-08/01
- Porsche 996 C4 3.4L 1997-08/01
- Porsche 996 C2 3.6L 09/01-2005
- Porsche 996 C4 3.6L 09/01-2005
- Porsche 996 C4S 3.6L 09/01-2005
- Porsche 996 TURBO 2000-05
- Porsche 996 GT2 2001-05
- Porsche 996 GT3 MKI 1999-02
- Porsche 996 GT3 MKII 2003>>
- Porsche 997 MK1 Carrera 2 3.6L 2005-08
- Porsche 997 MK1 Carrera 2S 3.8L 2005-08
- Porsche 997 MK1 GT2 2007-09
- Porsche 997 MKII Carrera C2 3.6L 2009-12
- Porsche 997 MKII Carrera C4 3.6L 2009-12
- Porsche 997 MKII Carrera C2S 3.8L 2009-12
- Porsche Cayman 2.7L 987C 2006-08
- Porsche Cayman S 3.4L 987C 2005-08
- Porsche Cayman 2.9L 987C MKII 2009-12
- Porsche Cayman S / R 3.4L 987C MKII 2009-12
The Brake Booster Bellow is a small but vital component of your braking system. This protective rubber sleeve seals the brake booster pushrod where it connects to the brake pedal assembly, keeping the booster airtight and free from contamination.
Over time, the bellow can crack or tear, leading to vacuum leaks, reduced brake assist, or even premature brake booster failure. Replacing it with this genuine OEM Porsche part restores proper sealing, protects the booster internals, and ensures safe, consistent braking performance.
Fits:
What This Product Does:
The brake booster bellow is a protective rubber sleeve that fits onto the brake booster unit. Its purpose is to seal and protect the brake booster pushrod where it connects to the brake pedal assembly.
Functions:
Symptoms Of A Faulty Or Worn Bellow:
- Hissing or vacuum leaks near the brake pedal.
- Spongy or inconsistent brake pedal feel.
- Reduced brake assist, making the pedal harder to press.
- Dirt or debris contamination around the booster rod.
- Visible cracks, splits, or deterioration in the rubber.
The bellow is a small but important part of the brake system. A damaged or missing boot allows dust and moisture into the booster, which can lead to internal corrosion, vacuum leaks, and reduced braking performance.
Diagram Ref No 22
Related reference numbers
Related, superseded, cross reference or alternative numbers for comparison.
99642326905
The product you are viewing cross references to these numbers
- Porsche 997 MK1 Carrera 4 3.6L 2005-08
- Porsche 997 MK1 Carrera 4S 3.8L 2005-08
- Porsche 997 MK1 TURBO 2007-09
- Porsche 997 MK1 GT3 2007-09
- Porsche 997 MKII Carrera C4 3.6L 2009-12
- Porsche 997 MKII Carrera C4S 3.8L 2009-12
- Porsche 997 MKII GT3 2010-11
- Porsche 997 MKII Turbo 2010-13

Fits:
Porsche 997.1 C4 / C4S 2005-08
Porsche 997.1 Turbo 2007-09 (not for GT2)
Porsche 997.2 C4 / C4S 2009-12 Cars with Ceramic brakes (option code: 450)
Porsche 997.2 Carrera GTS / 4 GTS 2009-12
Porsche 997.2 Turbo 2010-13
Porsche 997 GT3 2007-11
Click 'Zoom in' for large parts diagram.
Diagram ref no 17
Related reference numbers
Related, superseded, cross reference or alternative numbers for comparison.
99735596900
The product you are viewing cross references to these numbers
- Porsche Boxster 986 2.5L 1997-99
- Porsche Boxster 986 2.7L 1999-02
- Porsche Boxster S 986 3.2L 1999-02
- Porsche Boxster 986 2.7L 2003-04
- Porsche Boxster S 986 3.2L 2003-04
- Porsche Boxster 987 2.7L 2005 -08/08
- Porsche Boxster 987 S 3.2/3.4L 2005-08/08
- Porsche Boxster 987 MKII 2.9L 2009-2012
- Porsche Boxster S 987 MKII 3.4L 2009-2012
- Porsche 996 C2 3.4L 1997-08/01
- Porsche 996 C4 3.4L 1997-08/01
- Porsche 996 C2 3.6L 09/01-2005
- Porsche 996 C4 3.6L 09/01-2005
- Porsche 996 C4S 3.6L 09/01-2005
- Porsche 996 TURBO 2000-05
- Porsche 996 GT2 2001-05
- Porsche 996 GT3 MKI 1999-02
- Porsche 996 GT3 MKII 2003>>
- Porsche 996 GT3 RS 2003-04
- Porsche 997 MK1 Carrera 2 3.6L 2005-08
- Porsche 997 MK1 Carrera 2S 3.8L 2005-08
- Porsche 997 MK1 Carrera 4 3.6L 2005-08
- Porsche 997 MK1 Carrera 4S 3.8L 2005-08
- Porsche 997 MK1 TURBO 2007-09
- Porsche 997 MK1 GT3 2007-09
- Porsche 997 MK1 GT2 2007-09
- Porsche 997 MKII Carrera C2 3.6L 2009-12
- Porsche 997 MKII Carrera C4 3.6L 2009-12
- Porsche 997 MKII Carrera C2S 3.8L 2009-12
- Porsche 997 MKII Carrera C4S 3.8L 2009-12
- Porsche 997 MKII GT3 2010-11
- Porsche 997 MKII Turbo 2010-13
- Porsche 997 MKII GT2 RS 2011-13
- Porsche Cayman 2.7L 987C 2006-08
- Porsche Cayman S 3.4L 987C 2005-08
- Porsche Cayman 2.9L 987C MKII 2009-12
- Porsche Cayman S / R 3.4L 987C MKII 2009-12
- Porsche 970.1 Panamera V6 3.6L 2WD 2009-13
- Porsche 970.1 Panamera 4 V6 3.6L 4WD 2009-13
- Porsche 970.1 Panamera S V8 4.8L 2009-13
- Porsche 970.1 Panamera 4S V8 4.8L 2009-13
- Porsche 970.1 Panamera GTS V8 4.8L 2011-13
- Porsche 970.1 Panamera Turbo V8 4.8L 2009-13
- Porsche 970.1 Panamera Turbo S V8 4.8L 2009-13
- Porsche 970.1 Panamera Diesel V6 3.0L 2011-13
- Porsche 970.1 Panamera S Hybrid V6 3.0L 2011-13
- Porsche 970.2 Panamera V6 3.6L 2WD (310Hp) 2014-16
- Porsche 970.2 Panamera 4 V6 3.6L 4WD (310Hp) 2014-16
- Porsche 970.2 Panamera S V6 Turbo 3.0L 2WD (420Hp) 2014-16
- Porsche 970.2 Panamera S V6 Turbo 3.0L 2WD Executive 2014-16
- Porsche 970.2 Panamera 4S V6 Turbo 3.0L 4WD (420Hp) 2014-16
- Porsche 970.2 Panamera 4S V6 Turbo 3.0L 4WD Executive 2014-16
- Porsche 970.2 Panamera GTS V8 4.8L 4WD (440Hp) 2014-16
- Porsche 970.2 Panamera Turbo V8 4.8L (520Hp) 2014-16
- Porsche 970.2 Panamera Turbo V8 Executive 2014-16
- Porsche 970.2 Panamera Turbo S V8 4.8L 2014-16
- Porsche 970.2 Panamera Diesel V6 3.0L (250Hp) 2014-16
- Porsche 970.2 Panamera S E-Hybrid V6 3.0L (416Hp) 2014-16

Fits:
Porsche 996 1998-05
Porsche 997.1 2005-08
Porsche 997.2 2009-12
Porsche 986 Boxster 1997-04
Porsche 987.1 Boxster 2005-08
Porsche 987.2 Boxster 2009-12
Porsche 987C.1 Cayman 2005-08
Porsche 987C.2 Cayman 2009-12
Porsche 970 Panamera 2010-16
Click 'Zoom in' for large parts diagram.
Diagram ref no 10
Related reference numbers
Related, superseded, cross reference or alternative numbers for comparison.
99635590101
The product you are viewing cross references to these numbers
High-Quality Brake Servo Units for Strong, Consistent and Safe Braking Performance
A brake servo—also known as a brake booster—is an essential part of the vehicle’s hydraulic braking system. It uses vacuum or pressure assistance to reduce the amount of force required on the brake pedal, allowing the driver to achieve strong, controlled braking with minimal effort. Whether used in classic models or modern braking systems, a healthy servo is critical for maintaining safe braking performance, predictable stopping distances and a comfortable pedal feel.
Brake servos are vital for both everyday driving confidence and high-demand situations where maximum braking efficiency is essential.
What a Brake Servo Does
Brake servos perform several key functions:
- Amplify
braking force using vacuum or hydraulic assistance
- Reduce
pedal effort, improving comfort and responsiveness
- Ensure
consistent braking pressure across varying driving conditions
- Improve
brake modulation, allowing smoother, safer braking
- Support
ABS and advanced braking systems by stabilising hydraulic pressure
- Enhance emergency braking performance when rapid deceleration is required
Without a properly functioning brake servo, braking becomes harder, less predictable and potentially unsafe.
Why Brake Servos Commonly Fail
Brake servos can wear out or malfunction due to age, usage
conditions and environmental factors. Typical causes of failure include:
- Vacuum
leaks in seals, diaphragms or hoses
- Internal
diaphragm rupture affecting assistance levels
- Corrosion
inside the servo housing from moisture intrusion
- Check
valve failure, causing loss of vacuum retention
- Brake
fluid contamination damaging internal components
- Wear
from sustained heavy braking in performance or towing environments
- Heat and age-related degradation of rubber components
Failure symptoms often include a hard brake pedal, poor braking efficiency, hissing noises, long stopping distances or inconsistent pedal feel.
Why You Should Replace a Faulty Brake Servo
Replacing a worn or failing servo with a high-quality,
precision-built alternative engineered to match original braking performance
specifications is essential for driver safety and system integrity.
Advantages include:
- Restored braking assistance and smoother pedal operation
- Reduced stopping distances and improved safety
- Reliable vacuum or hydraulic support under all driving conditions
- Correct functioning of ABS and other brake control systems
- Prevention of brake fade caused by excessive pedal effort
- Enhanced driving comfort, especially in urban and stop-start conditions
A new servo unit dramatically improves braking consistency and ensures your vehicle remains safe and responsive