Audi S4 B8 S5 8T 3.0 TFSI Quattro Rear Differential 35:9 0BF500043Q WARRANTY

Listing details

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

Audi S4 B8 S5 8T 3.0 TFSI Quattro Rear Differential 35:9 is a factory-original drivetrain component from the Differentials category, designed for installation on the rear axle of the quattro drive system. It is responsible for the precise distribution of torque to the rear wheels, ensuring stable handling, predictable traction, and safe utilization of the 3.0 TFSI engine's power. This is a solution for users who expect consistent drivetrain performance in line with Audi's factory specifications.

Specifications and technical data

• SKU: 0BF500043Q
• Mark: Audi
• Condition: Used
• OEM Part Number: 0BF500043Q
• Substitutable numbers: 0BF500043Q, 0BF 500 043 Q
• Location on the vehicle: Rear
• Category: Differentials

Purpose and function in the drivetrain

The rear differential in the Audi S4 B8 S5 8T 3.0 TFSI Quattro acts as a key component of the drive axle, responsible for transferring power from the driveshaft to the rear wheels and compensating for the difference in rotational speed between them. Thanks to the properly selected 35:9 gear ratio, the system maintains the correct acceleration characteristics, flexibility, and engine RPM, which translates into consistent vehicle behavior during both highway driving and dynamic acceleration.

The component is mounted in the rear axle area, working in conjunction with the driveshaft, half-shafts, and the quattro drive control electronics. A correctly selected and functional differential reduces jerking, excessive play in the drivetrain, and unwanted noises during acceleration and deceleration.

Benefits of using an original Audi differential

Using an original differential dedicated to the Audi S4 B8 S5 8T 3.0 TFSI Quattro allows you to maintain the vehicle's factory handling characteristics. Key advantages include:

• Gear ratio consistency – maintaining the correct drive ratio between the front and rear, which is particularly important in quattro systems.
• Stable cornering – proper operation of the differential limits wheel slip and supports predictable body behavior.
• Proper cooperation with vehicle electronics – electronic stability control and traction control systems operate based on the differential's factory parameters.
• Direct fitment – allows for installation in place of a worn component without the need for structural modifications.

Characteristics of the used component

The presented rear differential is a salvaged part, meaning it is a used component that retains its factory construction and geometry. This type of component is a good choice for repairs where matching the vehicle's original specifications is key, while simultaneously optimizing service costs. A used differential allows for the restoration of proper drivetrain operation in situations where the previous unit has suffered mechanical wear or operational damage.

Before installation, standard workshop procedures are recommended: verifying play, checking for leaks, changing the differential oil, and assessing the condition of mounts and cooperating suspension components. This approach increases the durability of the entire system and reduces the risk of repeated service interventions.

Gear ratio selection and quattro drive compatibility

In the case of the Audi S4 B8 S5 8T 3.0 TFSI Quattro, it is extremely important to maintain compatibility between the rear differential gear ratio and the other drivetrain components. An incorrectly selected gear ratio can lead to overloads, electronic system errors, and accelerated component wear. Therefore, when replacing the differential, it is worth verifying the vehicle's technical parameters and comparing them with the data of the part being replaced.

To better understand the relationship between the differential gear ratio and driving characteristics, it is worth checking out our guide: Salvaged drive axles and differentials – how to choose gear ratios for your driving style. The article discusses practical examples, definitions, and the most frequently asked questions related to selecting differentials and drive axles.

Expanding the Audi drivetrain – Differentials

If you are planning a comprehensive repair or upgrade of the drivetrain in your Audi and need other components from the same group, such as additional differentials, rear axles, or parts cooperating with the drivetrain, check out the available parts in the Audi Differentials category.