Overview
The ZF 4108.303.263 PIN is a precision-machined locating and retention component engineered for the WG100, WG130, and WG131 transmission series. This OEM genuine part functions as a critical alignment dowel within the valve body and housing interface, ensuring that mating surfaces remain perfectly indexed under high-torque loads and thermal cycling. The SKU 4108.303.263 is often replaced during a full transmission rebuild to prevent misalignment that can lead to premature wear of adjacent assemblies. This pin works in concert with the 4108101112: HOUSING and the 4108201177: HOUSING to maintain structural integrity within the gear train.
Symptoms of Failure
- Intermittent gear engagement hesitation – A worn or sheared pin allows the housing to shift slightly, causing delayed clutch pack engagement during upshifts.
- Persistent oil seepage at housing seams – When the pin loses its interference fit, the 0636302056: SCREW PLUG and gasket surfaces can no longer seal properly, leading to external fluid leaks.
- Abnormal metallic rattling from the bell housing – Loose pin fit permits micro-movement of the 4108301304: BEARING COVER, generating a distinct chatter at idle.
- Hard shifting between 2nd and 3rd gear – Misalignment caused by a degraded pin alters the shift valve timing, producing harsh engagement under load.
Technical Specifications
| Parameter | Value |
|---|---|
| OEM Part Number | 4108.303.263 |
| Material | Case-hardened alloy steel (SAE 8620 equivalent) |
| Overall Length | 32.5 mm |
| Outer Diameter | 10.0 mm (ground finish) |
| Weight | 18 grams |
| Surface Treatment | Black oxide with phosphate undercoat |
| Hardness | 58-62 HRC (case depth 0.8 mm) |
Compatibility
This pin is specifically validated for the ZF WG100, WG130, and WG131 series transmissions used in medium-duty commercial vehicles and off-highway equipment. It also fits select variants of the WG180 and WG200 when used in conjunction with the correct 4108306173: GASKET and 0750110040: SHAFT SEAL. Always verify housing bore condition before installation; the pin must be paired with a matching 4108102042: INPUT shaft assembly to ensure concentricity.
Related Components
| Part Number | Name | Function |
|---|---|---|
| 4108101112 | HOUSING | Main transmission case that houses the gear sets |
| 4108201177 | HOUSING | Rear housing section supporting output shaft bearings |
| 0636302056 | SCREW PLUG | Seals hydraulic passages in the valve body |
| 4108301304 | BEARING COVER | Retains the main shaft bearing in the housing bore |
| 4108306173 | GASKET | Prevents oil migration between housing flanges |
| 0750110040 | SHAFT SEAL | Dynamic seal for the input shaft |
| 4108102042 | INPUT | Input shaft assembly transferring engine torque |
| 4108302099 | PLANET CARRIER | Supports planetary gear sets for torque multiplication |
| 4108302007 | BEARINGSHEET | Thrust washer sheet for axial load distribution |
| 0635332196 | BALL BEARING | Radial support for rotating shafts |
