Overview
The ZF 0631.328.587 SLOTTED PIN is a precision-engineered locating and alignment component specifically designed for the valve body and housing assemblies within ZF WG100, WG130, and WG131 transmissions. This OEM genuine part ensures correct positioning of internal hydraulic circuits, preventing cross-leakage between channels and maintaining proper clutch pack engagement timing. The slotted design allows for secure retention and facilitates accurate assembly during rebuilds. The SKU 0631.328.587 is manufactured to ZF’s exacting tolerances, guaranteeing a direct fit without modification. When installed alongside the 4143101009: HOUSING or the 4143301025: HOUSING, this pin provides the critical mechanical stop necessary for proper shift feel and pressure regulation.
Symptoms of Failure
- Erratic shift timing and delayed engagement: A worn or sheared slotted pin allows the valve body to shift out of alignment, causing hesitation when moving from neutral to drive or reverse.
- Internal hydraulic cross-leakage and pressure loss: When the pin fails, the 0634313603: O-RING seals can no longer maintain proper compression, leading to low line pressure and slipping clutches.
- Audible metallic rattling from the transmission pan: A broken pin fragment can fall into the sump, creating noise and potentially damaging the 4475280018: SCREW PLUG or other valve body components.
- Inability to hold gear under load: Misalignment caused by a deformed pin prevents the shift valves from fully seating, resulting in gear flare or complete loss of drive.
Technical Specifications
| Specification | Detail |
|---|---|
| Part Number (OEM) | 0631.328.587 |
| Type | Slotted Alignment Pin |
| Material | Case-Hardened Steel (C10E / 1.1121) |
| Overall Length | 28.5 mm (estimated) |
| Outer Diameter | 8.0 mm (estimated) |
| Slot Width | 2.0 mm (estimated) |
| Weight | Approx. 11 grams |
| Surface Finish | Phosphate coated for corrosion resistance |
| OEM Reference | ZF 0631.328.587 |
Compatibility
This slotted pin is engineered for the following ZF transmission models: WG100, WG130, and WG131. It is also commonly found in the valve body assemblies of WG180 and WG200 series transmissions where the same housing architecture is employed. Always verify the pin location within the main control bore before installation. For complete sealing integrity, we recommend replacing the 0634313591: O-RING and the 0501342341: SUPPORT RING concurrently with this pin.
Related Components
| Part Number | Name | Function |
|---|---|---|
| 4143101009 | HOUSING | Main transmission housing casting |
| 4143301025 | HOUSING | Valve body housing section |
| 0634313603 | O-RING | Hydraulic seal for valve body bore |
| 4475280018 | SCREW PLUG | Pressure port sealing plug |
| 0501342341 | SUPPORT RING | Backup ring for O-ring extrusion |
| 4143298457 | SEAL KIT | Complete gasket and seal set |
| 0634313591 | O-RING | Secondary hydraulic seal |
| 0636101068 | CAP SCREW | Fastener for housing assembly |
| 4143221013 | THROTTLE VALVE | Pressure modulation valve |
| 0634304484 | O-RING | Throttle valve bore seal |
