Overview
The ZF 0636.100.630 HEXAGON SCREW is a critical OEM genuine fastener engineered for secure clamping within the differential assembly of WG100, WG130, and WG131 transmissions. This hexagon screw directly retains the 2098309011: CROWN WHEEL to the differential housing, ensuring precise torque transfer under high-load conditions. As a factory-spec component, SKU 0636.100.630 eliminates the risk of fastener fatigue that can compromise the entire drivetrain assembly. It is commonly replaced during overhauls involving the 2098109042: DIFFERENTIAL or when resealing the 2098309010: DIFFERENTIAL HOUSING.
Symptoms of Failure
- Oil seepage at differential housing bolt holes: A worn or stretched hexagon screw 0636.100.630 can lose clamping force, allowing transmission fluid to weep past the 2099209001: DIFFERENTIAL mating surfaces.
- Audible clunking during gear engagement: Loosened fasteners permit micro-movement between the crown wheel and housing, producing a metallic knock under load.
- Increased backlash in the driveline: When this screw fails to maintain preload, rotational play develops between the differential and axle bevel gears, causing delayed power delivery.
- Vibration at highway speeds: Uneven torque distribution from a compromised hexagon screw leads to harmonic imbalance in the final drive assembly.
Technical Specifications
| Specification | Value |
|---|---|
| Part Number | 0636.100.630 |
| Type | Hexagon Screw (Socket Head Cap Screw) |
| Thread Size | M10 x 1.5 (estimated) |
| Length | 30 mm (estimated) |
| Material | High-tensile alloy steel, zinc-plated |
| Weight | 0.035 kg (approx.) |
| OEM Reference | ZF 0636.100.630 |
| Torque Specification | 45 Nm + 90° (factory spec) |
Compatibility
This hexagon screw is specifically validated for ZF WG100, WG130, and WG131 transmission models. It is also commonly used in the differential sub-assemblies of WG180 and WG200 series when paired with the 2098309031: AXLE BEVEL GEAR or 2098309030: AXLE BEVEL GEAR. Always verify thread pitch and length against your existing hardware; this screw is not interchangeable with standard metric bolts due to its specific shank design.
Related Components
| Part Number | Name | Function |
|---|---|---|
| 2098109042 | DIFFERENTIAL | Distributes torque to axle shafts |
| 2098309011 | CROWN WHEEL | Transfers power from pinion to differential |
| 2099209001 | DIFFERENTIAL | Complete differential assembly variant |
| 2098309010 | DIFFERENTIAL HOUSING | Encloses differential gears and bearings |
| 2098309009 | DIFFERENTIAL HOUSING | Alternate housing casting for WG series |
| 2098309031 | AXLE BEVEL GEAR | Drives axle shaft rotation |
| 2098309030 | AXLE BEVEL GEAR | Matching bevel gear for differential |
| 2098309032 | DIFFERENTIAL BEVEL GEAR | Planetary gear within differential |
| 12883200682 | THRUST WASHER | Reduces axial friction in differential |
| 0635332059 | BALL BEARING | Supports differential shaft rotation |
