Audi S8 D3 5.2 FSI Quattro Rear Differential 32:9 HNM 0AR500043B WARRANTY

Listing details

The differential is sold with a 90-day warranty! It was tested before removal and is in full working order.

Audi S8 D3 5.2 FSI Quattro Rear Differential 32:9 HNM is an original drivetrain component from the Differentials group, designed for installation on the rear axle in Audi models with quattro all-wheel drive. This used rear differential provides a functional solution for advanced drivetrain repairs, allowing for the restoration of proper rear differential operation while maintaining factory gear ratio specifications.

Specifications and technical data

• SKU: 0AR500043B
• Mark: Audi
• Condition: Used
• OEM Part Number: 0AR500043B
• Substitutable numbers: 0AR500043B, 0AR 500 043 B
• Location on the vehicle: Rear
• Category: Differentials

Purpose and function of the rear differential

The presented rear differential is dedicated to luxury Audi A8 sedans and sport S8 versions of the D3 generation with the 5.2 FSI CFSA engine and quattro drive. As a component of the rear drivetrain, it is responsible for torque distribution to the rear wheels, working in conjunction with the central quattro system and vehicle electronics. The applied 32:9 gear ratio ensures consistency with the factory drivetrain configuration, which is crucial for both dynamics and the durability of other components.

Construction and technical characteristics

The rear differential has been designed as an integral part of the rear axle, adapted to operate in the demanding conditions of premium-class vehicles. The construction is intended for installation in the rear position, maintaining factory mounting points and compatibility with the stock suspension and axle shafts. This allows for the restoration of the original drivetrain geometry without the need for modifications to the body or suspension structure.

The differential included in the assembly works with the quattro system, ensuring appropriate power distribution on the rear axle. A properly selected gear ratio translates into predictable vehicle behavior, stability at higher speeds, and correct operation of assistance systems such as traction control or electronic stability control.

Service and repair application

A used rear differential is a practical solution in situations involving mechanical damage to the differential, gear wear, or failure following a collision. Replacing the complete rear differential often reduces repair time compared to disassembling and rebuilding individual components, while simultaneously maintaining gear ratio consistency with the rest of the drivetrain.

Before installation, standard service procedures are recommended: checking for leaks, verifying operational clearances, assessing the condition of mounts, and changing the differential oil according to the vehicle manufacturer's recommendations. This approach increases the chances of long-term and stable operation of the entire drivetrain after replacement.

Gear ratio selection and quattro compatibility

For all-wheel-drive vehicles, gear ratio compatibility between the rear differential, the main transmission, and the front differential (if applicable) is critical. An incorrectly selected gear ratio can lead to excessive stress in the system, accelerated wear, or electronic system errors. Therefore, when replacing the rear differential in an Audi A8 or S8 D3, it is worth paying special attention to matching it to the specific quattro drivetrain configuration.

To better understand the relationships between gear ratios, differential characteristics, and driving style, the guide article Used drive axles and differentials – how to choose gear ratios for your driving style, which discusses practical examples and frequently asked questions related to selecting used drivetrain components, will be helpful.

AWD systems and Audi-specific solutions

The quattro system used in the Audi A8 and S8 D3 is an advanced AWD system where proper operation depends on the cooperation of many components – from the transmission and central drive distribution system to the rear differential. Using the correct rear differential allows for the preservation of the traction characteristics, cornering stability, and predictable vehicle behavior on surfaces with varying grip levels that are characteristic of quattro.

For those interested in a broader comparison of AWD solutions from various manufacturers, including the quattro system, the material xDrive, 4Matic, quattro or 4Motion – a comparison of AWD systems from BMW, Mercedes, Audi and VW, which describes the design and service differences between popular all-wheel-drive systems, may be useful.

Expanding repairs within Audi differentials

If you are planning a comprehensive repair or upgrade of the drivetrain area in your Audi and need other elements from the same group, such as additional differentials, housings, or complete axle assemblies, check the available parts in the Audi Differentials category.