Brake Booster
- 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 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

Fits:
Porsche 986 Boxster 1997-04
Porsche 996 1995-08
Click 'Zoom in' for large parts diagram.
Diagram ref no 16
Related reference numbers
Related, superseded, cross reference or alternative numbers for comparison.
99642330100
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 S 3.2/3.4L 2005-08/08
- 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 Cayman S 3.4L 987C 2005-08
Fits:
Porsche 986 Boxster 1997-04
Porsche 987 Boxster S 2005-08 (I450 - cars with Ceramic Brake)
Porsche 987C Cayman S / Cayman R 2005-08 (I450- cars with Ceramic Brake)
Porsche 996 Carrera 1998-05
Porsche 996 Turbo 2001-05
Click 'Zoom in' for large parts diagram
Diagram ref no 4
Related reference numbers
Related, superseded, cross reference or alternative numbers for comparison.
99635592300
The product you are viewing cross references to these numbers
High-Quality Brake Boosters for Safe, Effortless and Consistent Braking Performance
Brake boosters—also known as power brake boosters—are essential hydraulic components that amplify the force applied to the brake pedal. By using vacuum or hydraulic pressure assistance, the brake booster helps deliver strong braking performance with minimal driver effort. Whether driving a classic car or a modern performance vehicle, a properly functioning brake booster ensures predictable stopping distances, stable pedal feel and safe braking under all conditions.
A healthy booster is key to driving comfort, road safety and confidence—especially in emergency braking situations or repeated heavy braking.
What Brake Boosters Do
Brake boosters enhance braking capability by performing
several critical functions:
- Amplifying
pedal input, providing stronger braking force with less effort
- Improving
braking response for smoother, quicker stopping
- Maintaining
stable brake pressure across varying driving conditions
- Supporting ABS and advanced brake control systems
- Reducing
driver fatigue during heavy or frequent braking
- Helping maintain consistent performance in both low-speed and high-speed situations
With a properly functioning booster, brakes feel more responsive, controlled and progressive.
Why Brake Boosters Commonly Fail
Brake boosters can wear out due to age, heat, vacuum loss or
hydraulic issues. Common failure causes include:
- Vacuum
leaks from damaged hoses or internal seals
- Diaphragm
failure leading to loss of brake assistance
- Internal
corrosion caused by moisture buildup
- Faulty
check valves preventing vacuum retention
- Brake
fluid contamination damaging internal components
- Heat-related
degradation of diaphragms and seals
- Wear due to high mileage or repeated heavy braking
Symptoms often include a hard brake pedal, increased stopping distances, hissing noises, inconsistent pedal feel or warning lights.
Why You Should Replace a Faulty Brake Booster
Replacing a worn or failing brake booster with a high-quality, precision-engineered alternative designed to match original braking performance ensures your vehicle remains safe and responsive.
Key benefits include:
- Restored braking assistance and lighter pedal effort
- Improved stopping power and safety in all conditions
- Consistent pedal feel with predictable braking response
- Prevention of brake fade due to excessive pedal force
- Reliable operation of vacuum-dependent brake systems
- Peace of mind during emergency or high-load braking situations
A new brake booster significantly improves braking comfort and reliability, making it an essential maintenance replacement for any vehicle with reduced brake assist.