Overview
The ZF 0631.607.023 SET SCREW is a precision-engineered OEM fastening component specifically designed for the WG100, WG130, and WG131 transmission series. This set screw functions as a critical locking element within the valve body or housing assembly, securing internal passages and preventing unwanted fluid bypass. As a genuine ZF part, SKU 0631.607.023 ensures exact thread pitch and material hardness to maintain hydraulic pressure integrity. When installed alongside the 4108101031: HOUSING or the 4108303155: HOUSING, this set screw provides the necessary clamping force to keep the transmission’s internal architecture stable under high-torque conditions.
Symptoms of Failure
When the 0631.607.023 set screw wears or loosens, operators may notice several distinct failure modes. Transmission fluid seepage around the valve body is a primary indicator, as the compromised seal allows oil to escape past the threads. Erratic gear engagement or delayed shifting often follows, since hydraulic pressure drops when the screw no longer holds its mating component firmly. Another common symptom is audible rattling from the transmission housing during idle or low-speed operation, caused by vibration of loose internal parts. Finally, intermittent loss of drive in specific gears can occur if the set screw backs out and obstructs a shift valve, a condition frequently searched as “ZF transmission slipping after repair.”
Technical Specifications
| Part Number | 0631.607.023 |
| Type | Set Screw (Hex Socket) |
| Thread Size | M8 x 1.25 (estimated) |
| Length | 16 mm (estimated) |
| Material | Case-hardened steel, zinc-plated |
| Weight | ~8 g |
| OEM Reference | ZF 0631.607.023 |
| Torque Spec | 12 N·m (dry, estimated) |
Compatibility
This set screw is factory-specified for ZF WG100, WG130, and WG131 series transmissions. It is also commonly used in WG180 and WG200 variants where the same valve body architecture is employed. The part interfaces directly with the 0636302015: SCREW PLUG and the 0630361037: SEALING CAP to create a complete fluid containment system. For rebuilds involving the 4108108019: INTERM.GEARBOX, always verify that the 0631.607.023 set screw is torqued to factory specifications to avoid cross-threading.
Related Components
| Part Number | Name | Function |
|---|---|---|
| 4108101031 | HOUSING | Main transmission housing for WG series |
| 4108303155 | HOUSING | Secondary housing for valve body assembly |
| 0636302015 | SCREW PLUG | Seals hydraulic passages in valve body |
| 0630361037 | SEALING CAP | Protects threaded bores from debris |
| 0730361010 | SEALING CAP | Alternate cap for larger diameter ports |
| 0736305007 | SCREW PLUG | High-pressure plug for accumulator circuits |
| 0634801165 | SEALING RING | Copper washer for leak-proof sealing |
| 0730365280 | TYPE PLATE | Identification plate for transmission model |
| 0631311009 | GROOVED STUD | Alignment stud for housing positioning |
| 4108108019 | INTERM.GEARBOX | Intermediate gearbox assembly for WG series |
