Audi R8 4S bj2017 front axle gear 0D4409505B

Part Number: 0D4409505B (0D4 409 505 B)

Differential Codes: QQL / RZS

Application: Audi R8 4S 5.2 FSI V10 (Quattro)

Model Year: 2015–2018 (Pre-Facelift / Early Gen 2)

The 0D4409505B is the front axle drive (Vorderachsgetriebe) for the second-generation Audi R8 (Type 4S). Unlike the first-generation R8, which used a purely mechanical viscous coupling, the 4S generation utilizes an electronically controlled multi-plate clutch system. This allows for fully variable torque distribution between the front and rear axles, significantly improving traction and cornering dynamics.

Technical Specifications

• Drive System: Quattro AWD with electronic regulation.

• Transmission Compatibility: 7-Speed S-tronic (DL800 / 0BZ).

• Gear Ratio: Commonly matched with final drive ratios for the $5.2\text{ FSI}$ V10 and V10 Plus (approx. $3.59$ or $3.58$ depending on the specific gearbox pairing).

• Cooling: Passive heat-sink cooling integrated into the aluminum housing.

• Integration: Mounted at the front axle, receiving power from the longitudinal cardan shaft.

Key Performance Features

• Variable Torque Split: The mechatronic unit inside this differential can shift from 0% to 100% of available torque to the front wheels in milliseconds.

• Electronic Clutch Management: Instead of a mechanical diff lock, it uses active pressure to engage the internal clutch plates, allowing for “predictive” AWD engagement based on throttle position and steering angle.

• Lightweight Design: Compact housing designed to fit within the R8’s tight front-end packaging while maintaining high structural rigidity for the $610\text{ PS}$ drivetrain.

Professional Installation & Cataloging Notes

1. Haldex/Clutch Service: This unit contains a specific multi-plate clutch assembly (often colloquially referred to as the Haldex portion, though it is a specialized Audi Sport unit). If buying a used unit, verify that the internal clutches are not “burned” (blackened fluid or friction smell).

2. Fluid Requirements: This unit uses High-Performance Clutch Oil (G 060 175 A2) for the electronic coupling and standard High-Performance Axle Oil (G 052 145 S2) for the gear section. Ensure these two distinct reservoirs are correctly filled.

3. Calibration: After installation, the AWD Control Module (J492) must be calibrated to the new differential. A “Basic Setting” must be performed via Audi ODIS or VCDS to ensure the pump pressure and clutch kiss-points are accurate.

4. Pinion/Seals: Inspect the input flange (where the driveshaft connects) for any radial play. Leaking seals on the input or output stubs should be replaced with genuine Audi seals (0D4 409 189) before the differential is mounted in the car.

Inventory Note: This part number (0D4409505B) is specifically for the Quattro (AWD) models. It is not used on the RWS (Rear Wheel Series) models, which omit the front axle gear entirely to save weight.