Replacing a rack and pinion on a 2004 Porsche requires the correct part number to ensure proper fit and performance. Using the wrong unit can lead to alignment issues, steering problems, and wasted time. This guide helps you identify the exact OEM part number for your specific 2004 Porsche model, whether you have a 911 (996), Boxster (986), or Cayenne (955). We'll cover how to locate your VIN to confirm compatibility, list the most common rack and pinion part numbers for each model, and offer practical advice for choosing between OEM and aftermarket options.
Identifying Your 2004 Porsche Model
Before ordering a replacement, you need to know which generation and platform your Porsche uses. For 2004, the lineup includes:
- Porsche 911 (996.2) – The 996.2 facelift ran from 2002 to 2005. It uses a hydraulic rack and pinion system.
- Porsche Boxster (986) – The first-generation Boxster (1997–2004) also uses a hydraulic rack, similar to the 911 but with different mounting points.
- Porsche Cayenne (955) – The first-generation Cayenne (2004–2006) uses a hydraulic rack designed for the SUV platform.
Each model has unique part numbers due to differences in steering geometry, fluid lines, and sensor attachments.
Rack and Pinion Replacement Part Numbers by Model
For 2004 Porsche 911 (996)
The 996.2 rack and pinion is shared between the Carrera and Carrera S, except for minor variations depending on the steering rack supplier (ZF vs. TRW). The most common OEM part number for a standard 2004 911 is:
- 996-347-012-03 – Complete hydraulic rack assembly (left-hand drive).
- 996-347-012-04 – Right-hand drive version.
Some late 2004 models may use the updated part 996-347-012-05, which includes improved seals. Always verify by checking the original part sticker on your current rack. If your car has the optional “Porsche Stability Management” (PSM), the rack includes an additional sensor port, but the part number remains the same.
For 2004 Porsche Boxster (986)
The 986 Boxster rack is lighter but structurally similar to the 996. The correct OEM part number is:
- 986-347-012-02 – Standard rack for all 2004 Boxster models (left-hand drive).
- 986-347-012-03 – Right-hand drive version.
If your Boxster has the factory sport suspension, the steering ratio may differ, but the physical rack housing is the same. Always confirm with your VIN to avoid ordering a rack meant for a Boxster S (which uses a slightly different valve).
For 2004 Porsche Cayenne (955)
The Cayenne’s rack and pinion is larger and supports the vehicle’s weight and towing capability. The primary part numbers are:
- 955-347-012-01 – Standard hydraulic rack for 2004 Cayenne V6 and V8 (left-hand drive).
- 955-347-012-02 – Right-hand drive version.
- 955-347-012-03 – Heavy-duty rack for Cayenne Turbo and Turbo S (includes additional cooling lines).
Note that the 2004 Cayenne S and Turbo use different tie rod ends and inner joints compared to the base V6. The rack itself is the same for V8 models, but the part number suffix changes with the inclusion of an external fluid cooler.
How to Verify Your Part Number
The only way to guarantee the correct rack is to check your car’s VIN. The VIN is located at the base of the windshield on the driver’s side, as well as on the driver’s door jamb sticker. Write it down and contact a Porsche dealership parts department or use an online OEM parts database with your VIN. Cross-reference the original part number stamped on your leaking or damaged rack before purchasing a replacement.
Additionally, note that some 2004 models may have a metal stamp near the hydraulic fluid inlet on the rack itself. That number often matches the OEM part number exactly. If the number is worn away, measuring the length of the rack body and counting the number of tie rod thread turns can help identify it, but VIN lookup is far more reliable.
OEM vs Aftermarket Rack and Pinion Options
- OEM (Original Equipment Manufacturer) – Genuine Porsche racks offer perfect fit, factory warranty, and matched steering feel. They are more expensive, typically $800–$1,200 for the part alone. For a 2004 car, OEM is often the best choice if you plan to keep the car long-term.
- Remanufactured OEM – Many suppliers rebuild used OEM racks with new seals, bushings, and valves. These cost $300–$600 and include a core charge. Quality varies, so choose a reputable rebuilder with a warranty.
- Aftermarket (new) – Brands like ACDelco, Cardone, and TRW (licensed) offer new or reman racks at lower prices. Be cautious with cheap imitations—steering feel and durability may suffer. For a 2004 Porsche, a mid-range aftermarket rack can be a decent budget option if you replace the tie rods and flush the system.
Avoid rebuilt parts that do not come from a specialized steering rebuilder, as improper seal installation can cause premature failure.
Common Symptoms of a Failing Rack and Pinion
If you’re searching for a replacement part number, you likely already have symptoms. Typical signs include:
- Fluid leaks – Puddles of power steering fluid under the car, especially near the driver or passenger side.
- Steering wheel play – Excessive free play or a “loose” feeling when turning.
- Whining noise – Air in the system from low fluid or a worn pump, often accompanied by a groaning sound.
- Uneven tire wear – Worn internal seals cause improper fluid pressure, leading to wandering alignment.
- Stiff steering – The rack binds internally, making low-speed maneuvers difficult.
If you experience any of these, replace the rack promptly to avoid damaging the power steering pump or steering column.
Final Recommendation
For a 2004 Porsche, the safest choice is an OEM rack from a dealer or a certified parts retailer. Use your VIN to confirm the exact part number—don’t guess based on model alone. If cost is a concern, a high-quality remanufactured unit from a reputable steering specialist is acceptable, but avoid generic aftermarket brands. Always replace the tie rod ends, boots, and power steering fluid when installing a new rack. Following these steps will restore your Porsche’s steering precision and reliability for years to come.