OVERVIEW
Genuine M10×65 hardware for the exact assigned connection
N-102-638-01 is the Genuine VW/Audi M10×65 hexagon-head bolt. Confirmed applications below include the specified A4 crankshaft main-bearing connection and a separate Audi 200 steering-gear attachment.
The same factory number can serve different assigned assemblies. Use the application column to identify the correct purpose on your vehicle and restore the original hardware arrangement.
Technical details
- Complete factory number: N-102-638-01.
- Factory specification: M10 × 65.
- Design: external hexagon-head bolt.
- Quantity supplied: one individual bolt.
Thread diameter and length are only part of the identification. For the A4 main-bearing application, the factory separates AEB/ATW M10×65 hardware from AWM M10×80 hardware. Do not interchange them based on the vehicle badge alone.
Common reasons to replace
- Threads or the hexagon head are damaged.
- The bolt is missing during assembly work.
- The head or bearing surface is distorted.
- Incorrect hardware was installed during an earlier repair.
- The factory procedure requires a replacement for the serviced connection.
Inspect the receiving threads and mating surfaces. For main-bearing work, verify cap identity, orientation and bearing clearances according to the engine procedure. For steering work, inspect the mounting assembly and original washer or spacer arrangement separately.
Vehicle fitment
Match the engine code, body style and exact connection. The Audi 200 steering application does not imply that this bolt is its crankshaft main-bearing fastener.
| Vehicle | Model years | Engine | Configuration | Application restrictions |
|---|---|---|---|---|
| Audi A4 | 1997–2000 | 1.8L turbocharged gasoline I4; AEB or ATW | B5 sedan; front-wheel drive or quattro; Original crankshaft main-bearing cap connection | AEB/ATW engine only; original N10263801 M10×65 main-bearing bolt. Excludes AWM M10×80 positions. |
| Audi A4 | 1999–2000 | 1.8L turbocharged gasoline I4; AEB or ATW | B5 Avant; quattro; Original crankshaft main-bearing cap connection | AEB/ATW engine only; original N10263801 M10×65 main-bearing bolt. Excludes AWM M10×80 positions. |
| Audi 200 quattro | 1991 | 2.2L turbocharged 20-valve gasoline I5; 3B | Sedan or Avant; left-hand drive; Original steering-gear assembly attachment | Only original N10263801 M10×65 steering attachment. Confirm original washer and mating hardware. |
Installation guidance
Follow the factory repair procedure for the actual assembly. Main-bearing service requires the specified cap sequence, bolt preparation and tightening method. Steering attachment work requires its own supporting and tightening instructions. Do not infer either procedure from the bolt size.
Complete all factory assembly and functional checks for the serviced system before returning the vehicle to service. Restore any additional single-use hardware as required.
Ordering information
One genuine bolt is supplied. Bearings, caps, steering components, washers and other hardware are not included. Confirm the original number and required quantity.