Overview
The ZF 0631.329.120 SPRING PIN is a precision-engineered OEM genuine component designed for the WG100, WG130, and WG131 transmission series. This small but critical fastener secures internal assemblies within the gearbox, ensuring proper alignment and load distribution during high-torque operations. As part of the Springs & Fasteners category, SKU 0631.329.120 functions as a locating pin that prevents axial movement of shafts and gears, directly impacting shift quality and drivetrain reliability. It is frequently replaced alongside the 2095101022: TRANSMISSION HOUSING or the 2095301025: TRANSMISSION HOUSING during major overhauls.
Symptoms of Failure
- Intermittent gear slipping under load: A worn spring pin can allow shift forks to drift, causing unexpected disengagement during acceleration.
- Unusual metallic rattling from the transmission housing: Loose pins create vibration and noise, especially at low RPMs.
- Hard or imprecise gear engagement: Misalignment due to a failed pin makes shifting feel notchy or requires extra force.
- Oil seepage around the pin bore: Though not a seal, a damaged pin can deform the housing bore, leading to minor leaks that require a new 0634304731: O-RING and 4475280150: SCREW PLUG to fully resolve.
Technical Specifications
| Parameter | Value |
|---|---|
| Part Number | 0631.329.120 |
| Type | Spring Pin (Slotted) |
| Material | Spring Steel (ISO 8752) |
| Diameter (Nominal) | 12 mm |
| Length | 40 mm |
| Weight | 0.035 kg |
| OEM Reference | ZF 0631.329.120 |
| Hardness | 420–520 HV |
| Surface Finish | Phosphate coated |
Compatibility
This spring pin is engineered for ZF WG-series transmissions, specifically the WG100, WG130, and WG131 models. It is also compatible with select variants of the WG180 and WG200 series where the pin bore dimensions match. Always verify fitment by cross-referencing your transmission’s parts manual. For related fasteners in the same assembly, consider the 0636011207: HEXAGON SCREW and 0636011188: HEXAGON SCREW for secure mounting.
Related Components
| Part Number | Name | Function |
|---|---|---|
| 2095101022 | TRANSMISSION HOUSING | Main structural casing for gear assembly |
| 2095301025 | TRANSMISSION HOUSING | Alternate housing variant for WG130 |
| 4475280150 | SCREW PLUG | Seals oil passages in the housing |
| 0634304731 | O-RING | Prevents fluid leaks at plug interfaces |
| 0636011207 | HEXAGON SCREW | Secures housing covers and flanges |
| 0636011188 | HEXAGON SCREW | Fastener for internal bracket mounts |
| 0730365280 | TYPE PLATE | Identification label for transmission model |
| 0501337897 | SPEED SENSOR | Monitors output shaft RPM |
| 0636101027 | CAP SCREW | High-torque fastener for bearing caps |
| 0631306155 | CYLINDRICAL PIN | Alignment dowel for housing halves |
