High-quality hydraulic power steering pump designed for Citroën C5 first and second generation. This pump restores precise, reliable steering feel and reduces steering effort at low speeds. Ideal for professional workshops and experienced DIY mechanics looking for a direct-fit replacement with OE cross-reference numbers. The unit is compatible with multiple OEM references (see Technical Information below), making it easy to find by part number during diagnostics or ordering.

Benefits And Application

This power steering pump delivers stable pressure up to 110 bar and a flow of approximately 7 l/min, ensuring responsive steering input and consistent hydraulic support under varied driving conditions. The 126 mm diameter, 6-groove pulley is designed for belt-driven installations common to Citroën C5 I and II vehicles. Fits vehicles equipped with hydraulic power steering systems where listed OE numbers match.

Technical Information

• Manufacturer: Stellantis (Citroën / Peugeot)
• Model: Citroën C5 I, Citroën C5 II
• Product Codes: 9636086680, 9632876780, 9633817680
• Other Numbers: 9640906480, 9640830987, 40077A, 4007X9

Installation Recommendations

• Always Work Safely: Support the vehicle securely on jack stands and follow the vehicle manufacturer’s safety procedures.
• Battery: Disconnect the vehicle battery before starting work to avoid electrical faults and ensure personal safety.
• System Depressurisation: Relieve hydraulic pressure according to service manual. Catch spilled fluid in a suitable container and avoid contamination of the hydraulic circuit.
• Line Handling: Cap or plug hydraulic lines immediately after disconnection to prevent air and dirt ingress. Replace any damaged hoses or seals.
• Seals And Fasteners: Fit new O-rings/seals where applicable and tighten mounting bolts to the manufacturer’s torque specifications.
• Belt And Pulley: Check drive belt condition and pulley alignment. Replace the belt if worn and ensure the pulley grooves match the belt profile.
• Fluid And Bleeding: Refill with the manufacturer-recommended hydraulic fluid. Bleed the steering system by turning the wheel lock-to-lock several times with the engine running (follow the workshop manual procedure) until no air remains and steering operates smoothly.
• Final Check: Inspect for leaks, verify pulley runout, and perform a test drive to confirm normal steering response.

How Replacement Is Performed

Replacement typically involves removing the accessory drive belt, disconnecting and capping hydraulic lines, unbolting the pump from its bracket, and installing the new pump with new seals. Reconnection, fluid refill and thorough bleeding of the system are essential. Depending on vehicle layout, expect the job to take between 1.5 and 3 hours in a professional workshop.

Why This Part Fails Most Often

• Seal And Hose Leakage: Ageing seals and deteriorated hoses are the most common causes of external leaks that lead to pump failure.
• Contamination: Dirt or degraded fluid causes accelerated wear of internal components (vanes, rotor), reducing pump efficiency.
• Overheating And Fluid Degradation: Excessive heat and old fluid reduce lubrication and increase wear.
• Belt Or Pulley Issues: Worn belts or misaligned pulleys place extra load on the pump bearings, causing premature failure.
• High Mileage Wear: Normal wear over long service life (commonly observed after 100,000–200,000 km depending on use and maintenance) can reduce performance and cause noise or leaks.

Recommendations For Buyers

Match the OE or product code listed in the Technical Information to your existing part before ordering. Replace associated seals, hoses and fluid during service to maximise the service life of the new pump. If you are not confident with hydraulic systems, have the replacement performed or checked by a qualified technician.