Overview
The ZF 0631.313.056 CYLINDRICAL PIN is a precision-engineered locating and retaining component designed for the planetary gearset and differential assemblies within ZF WG100, WG130, and WG131 heavy-duty transmissions. This OEM genuine part, identified by SKU 0631.313.056, functions as a critical alignment dowel, securing internal shafts and gear clusters to prevent rotational displacement under extreme torque loads. It is typically press-fitted into the differential housing or planet carrier, ensuring that mating components such as the 2095109012 DIFFERENTIAL remain correctly indexed during operation. Without this cylindrical pin, the entire gear train would lose its positional integrity, leading to catastrophic internal contact.
Symptoms of Failure
- Intermittent gear slipping under load: When the 0631.313.056 pin shears or wears, the 2095209037 DIFFERENTIAL can shift axially, causing momentary loss of drive torque during acceleration.
- Metallic grinding noise from the differential area: A worn cylindrical pin allows the 0750117075 TAPER ROLLER BEARING to misalign, producing a rhythmic scraping sound that intensifies in lower gears.
- Excessive backlash in the driveline: As the pin degrades, the 2095309059 DIFF.HOUSING experiences micro-movement, resulting in a noticeable clunk when shifting between forward and reverse.
- Oil contamination with metallic debris: A fractured pin sheds steel particles into the transmission fluid, often visible during routine drain intervals.
Technical Specifications
| Parameter | Value |
|---|---|
| Part Number | 0631.313.056 |
| Type | Cylindrical Pin (Dowel Pin) |
| Material | Case-hardened alloy steel (DIN 1.7131) |
| Diameter | 12 mm (nominal) |
| Length | 38 mm |
| Surface Hardness | 58-62 HRC |
| Weight | ~0.034 kg |
| OEM Reference | ZF 0631.313.056 |
Compatibility
This cylindrical pin is engineered for ZF’s WG-series powershift transmissions, specifically the WG100, WG130, and WG131 models. It is also commonly used in the differential carrier assemblies of WG180 and WG200 variants where the 2095309059 DIFF.HOUSING requires precise alignment. For WG250 and WG300 applications, verify the pin bore diameter before installation, as later revisions may use a larger dowel. The 0631.313.056 pin is not interchangeable with the shorter 0631329086 SPRING PIN used in valve body assemblies.
Related Components
| Part Number | Name | Function |
|---|---|---|
| 2095109012 | DIFFERENTIAL | Distributes torque to axle shafts |
| 0750117075 | TAPER ROLLER BEARING | Supports differential carrier rotation |
| 2095209037 | DIFFERENTIAL | Secondary differential unit for multi-axle |
| 2095309059 | DIFF.HOUSING | Encloses differential gears |
| 0631329086 | SPRING PIN | Retains shift fork components |
| 0730300820 | THRUST WASHER | Reduces axial friction in gear stack |
| 4482360002 | AXLE BEVEL GEAR | Transfers power to wheel ends |
| 2095309081 | DIFFERENTIAL AXLE | Cross-shaft for differential spider gears |
| 5838300811 | THRUST WASHER | Spacer for bevel gear clearance |
| 4482360001 | DIFFERENTIAL BEVEL GEAR | Side gear for differential action |
