Power Steering Pumps
- 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 Boxster 981 2.7L 2012-16
- Porsche Boxster 981 S / GTS 3.4L 2012-16
- Porsche Boxster 981 Spyder 3.8L 2016
The power steering pump converts engine power into hydraulic pressure for the power assisted steering system, enabling smooth, effortless steering and consistent responsiveness. Built to OE specification.
Fits:
* M657 - for cars with power assisted steering
Porsche 986 Boxster 1997 - 2004
Porsche 987.1 Boxster 2005 - 2008
Porsche 987C.1 Cayman 2005 - 2008
Porsche 996 Carrera 1998 - 2005
Porsche 997.1 Carrera 2005 - 2008
Diagram ref no 9
• Position on Vehicle: Mounted within the engine bay on the front accessory drive system, connected to the power-steering fluid reservoir and rack/column assembly.
• Cross-Reference / Alternative Numbers: OEM number 996 314 050 03 (sometimes referenced as 99631405003); supersedes part number 996 314 050 02.
• Applications: Replacement whenever the original pump shows symptoms such as whining noise, fluid leakage, reduced steering assist or erratic steering feel - helping to restore proper steering function and driver confidence.
The power steering pump is central to the assistive steering system, providing hydraulic pressure needed for effortless steering and precise control. When the pump begins to fail - through internal wear, leakage, or loss of hydraulic efficiency - drivers may experience noisy operation, heavier steering effort, or inconsistent responsiveness. Replacing it with a fresh unit restores hydraulic integrity, ensures consistent steering feel and prevents further wear on associated steering components.
When and why to replace:
• Steering becomes notably heavier or varied in effort than expected.
• Noticeable whining or groaning noise when steering, especially at low speeds.
• Visible fluid leakage from the pump or associated lines/fittings.
• After other steering components (rack, links) have been serviced - a failing pump would compromise the rebuild.
• On high-mileage vehicles where original pump has been in service long and may be approaching end-of-life.
Related reference numbers
Related, superseded, cross reference or alternative numbers for comparison.
99631405003
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 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 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 Cayman 2.7L 987C 2006-08
- Porsche Cayman S 3.4L 987C 2005-08
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Reconditioned Power Steering Pump. 99631405002
Reconditioned units are sold on an exchange basis, A surcharge of £161.03 will be held and then refunded when the old one is returned.
Fits:
Porsche 986 Boxster 1998-04
Porsche 987 Boxster 2005-08
Porsche 987C Cayman 2005-08
Porsche 996 Carrera 1998-05
Porsche 997 Carrera 2005-08
Please note: This product is sold on an exchange the deposit we will refund after you have returned your old part.
- The surcharge for this reconditioned part will be refunded when the exchange unit is received and approved by us and the relevant manufacturer.
- Please note, surcharge refunds often take an average of 6 to 8 weeks to be approved by the manufacturer.
- Acceptance of the exchange part is at the manufacturer's discretion, based on the part being fit for reconditioning.
- All surcharges and exchanges are subject to our terms and conditions.
PLEASE NOTE:
Related reference numbers
Related, superseded, cross reference or alternative numbers for comparison.
996314050X
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 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 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 Cayman 2.7L 987C 2006-08
- Porsche Cayman S 3.4L 987C 2005-08
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12 Month Warranty
Worldwide Delivery
Free delivery
Fits:
Porsche 986 Boxster - 1997 to 2004
Porsche 987.1 Boxster - 2005 to 2008
Porsche 987.1 Cayman - 2006 - 2008
Porsche 996 Carrera 2 / 4 / 4S- 1997 to 2005
Porsche 997.1 Carrera 2 / Carrera 4- 2005 to 2008
Porsche 997.1 Carrera 2S / Carrera 4S - 2005 to 2008
Click 'Zoom in' for large parts diagram.
Diagram ref no 11
Related reference numbers
Related, superseded, cross reference or alternative numbers for comparison.
99631443105
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 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 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
Shop Securely
12 Month Warranty
Worldwide Delivery
Express Delivery
Porsche Power Steering Pumps, Hoses & Radiators | Design911 Hydraulic Components for Smooth & Precise Handling
Power steering pumps, hoses, and radiators are the key components that ensure your Porsche’s steering system operates smoothly, quietly, and efficiently. The power steering pump pressurises hydraulic fluid, while hoses transport it throughout the system, and radiators (or coolers) regulate temperature to prevent overheating. Together, these components provide effortless steering control, precise feedback, and the responsive handling that defines Porsche driving performance.
At Design911, we offer a comprehensive range of power steering pumps, hoses, and radiators engineered for precision fitment, durability, and high-pressure operation. Manufactured using premium materials, each component is designed to perform under demanding conditions — whether for daily driving, performance tuning, or restoration projects. Our range helps maintain steering precision, extend component life, and deliver long-term reliability.
⚙️ What Do Power Steering Pumps, Hoses & Radiators Do?
These interconnected components form the core of your Porsche’s hydraulic steering system, providing consistent power assist and cooling for maximum control.
Core Functions:
• The pump generates hydraulic pressure to assist steering input.
• Hoses and pipes transport pressurised fluid throughout the system.
• The radiator (cooler) regulates temperature for consistent operation.
• Maintain smooth, controlled steering effort at all speeds.
• Protect the steering rack and pump from overheating and wear.
This system ensures that steering remains light yet responsive — essential for both precision handling and driver comfort.
Why Do Power Steering Components Fail or Degrade?
Due to constant exposure to heat, pressure, and fluid flow, these components are subject to gradual wear and degradation over time.
Common Causes of Failure Include:
• Leaks from aged seals, fittings, or cracked hoses.
• Contaminated or deteriorated steering fluid reducing lubrication.
• Pump bearing or vane wear from low or dirty fluid.
• Corrosion or pitting in metal pipes and radiators.
• Blocked cooling circuits leading to overheating.
Failure in any of these parts can cause noise, fluid leaks, stiff steering, or even total system failure — making timely replacement critical for safety and reliability.
Why Replace or Upgrade Your Porsche Power Steering Pumps, Hoses & Radiators?
Replacing worn or damaged power steering components restores hydraulic pressure, cooling efficiency, and overall steering feel. Upgrading to improved materials enhances longevity and performance, particularly for high-demand or motorsport applications.
Key Benefits:
• Restores smooth, responsive steering performance.
• Eliminates leaks, whine, or vibration from failing components.
• Extends the life of steering racks and seals.
• Constructed from corrosion- and heat-resistant materials.
• Available for Porsche 911, 944, 968, Boxster, Cayman, Panamera, Cayenne, and
Macan models.
• Ideal for maintenance, restorations, or high-performance upgrades.
Design911’s Porsche power steering pumps, hoses, and radiators combine engineering precision, reliability, and superior materials — ensuring your Porsche’s steering stays sharp, responsive, and fluid.
Highlights
• Premium Porsche power steering pumps, hoses, and
radiators.
• Engineered for precision fitment and reliable performance.
• High-pressure and temperature-resistant materials.
• Reduces steering effort and enhances handling comfort.
• Suitable for both classic and modern Porsche models.
• Perfect for servicing, restoration, or performance tuning.
