OVERVIEW
Clamp the original drive axle into its wheel hub
4B0-407-643 is the Genuine VW/Audi shoulder bolt for the specified axle-to-hub connections. It installs through the hub and bearing into the outer drive-axle end, using the original M14 × 1.5 × 73 mm specification.
This connection is sensitive to the correct bolt diameter and tightening procedure. The unsuffixed 4B0-407-643 is a different size from the M16 version carrying suffix A; matching only the first nine characters is insufficient.
Technical details
- Complete factory number: 4B0-407-643.
- Factory specification: M14 × 1.5 × 73 mm drive axle shoulder bolt.
- Design: black flanged bolt with internal hex drive and threaded shank.
- Quantity supplied: one individual axle bolt.
One individual bolt is supplied. Axle shaft, wheel hub, bearing and other hardware are separate. Nominal fastener dimensions describe the component and are not packaged shipping dimensions. Renew this bolt when removed as directed by the factory procedure.
Common reasons to replace
- The axle or wheel-bearing procedure requires a new outer axle bolt.
- The internal drive or threads are damaged.
- The bolt is corroded or physically damaged.
- The original fastener is missing or an incorrect size has been fitted.
Confirm the axle's thread size and original bolt before ordering. Inspect the hub, bearing and axle engagement for damage. Do not substitute the M14 bolt into an M16 axle or use it to compensate for damaged threads.
Vehicle fitment
The table retains the confirmed VIN and engine restrictions. Axle and hub changes within a model year can require a different bolt; compare the original installation.
| Vehicle | Model years | Engine | Configuration | Application restrictions |
|---|---|---|---|---|
| Volkswagen Passat | 1998–2001 | 1.8L turbocharged gasoline | B5 front-wheel-drive sedan or wagon | Original M14 axle-to-hub connection; through VIN 3B-1-049999. Later M16 applications use a different bolt. |
| Audi A4 | 1997–2000 | 1.8L turbocharged gasoline; AEB or ATW | B5 front-wheel-drive sedan | AEB/ATW engine and original M14 axle-to-hub fastener only; verify installed axle and original number. |
| Audi S4 | 2000–2001 | 2.7L twin-turbocharged gasoline V6 | B5 quattro; original M14 hub connection | Through VIN 8D-1-050000. From VIN 8D-1-050001 uses the larger M16 bolt in the specified configuration; match original axle and hub. |
Installation guidance
Follow the vehicle-specific axle and wheel-bearing procedure, including restrictions on loading or moving the vehicle with the axle connection loose. Use the correct tool, a new specified bolt and the required torque-angle sequence. Do not estimate tightening values.
Complete the prescribed hub, wheel and driveline checks and road test. Verify that there is no looseness, bearing noise or abnormal vibration.
Ordering information
One individual Genuine VW/Audi 4B0-407-643 axle shoulder bolt, M14 × 1.5 × 73 mm. Confirm original thread size and applicable VIN restriction. Other axle hardware is separate.