Overview
The ZF 0636.309.009 SCREW PLUG is a critical sealing component engineered for the WG100, WG130, and WG131 transmission series. This OEM genuine part functions as a threaded closure within the transmission housing, preventing fluid loss and maintaining internal pressure integrity. Positioned strategically in the valve body or sump area, the SKU 0636.309.009 ensures that hydraulic circuits remain sealed during high-torque operations. When paired with the 4108101112: HOUSING or the 4108201177: HOUSING, this screw plug provides a secure barrier against contamination ingress, directly supporting transmission longevity.
Symptoms of Failure
When the 0636.309.009 screw plug wears or loosens, operators may notice specific failure indicators. Oil seepage around the plug threads is the most common sign, often visible as a slow drip near the transmission pan. Erratic gear engagement or delayed shifting can occur due to pressure loss in the hydraulic system. Unusual whining noises from the transmission may indicate air ingestion through a compromised seal. Low fluid levels without visible external leaks suggest internal weeping past the plug, requiring immediate replacement to avoid planetary gear damage.
Technical Specifications
| Specification | Detail |
|---|---|
| Part Number | 0636.309.009 |
| Material | Steel with zinc plating |
| Thread Size | M18 x 1.5 |
| Head Type | Hex socket (8mm) |
| Weight | 0.02 kg (0.04 lbs) |
| OEM Reference | ZF 0636.309.009 |
| Torque Spec | 25 Nm (18.4 ft-lbs) |
Compatibility
This screw plug is directly compatible with ZF WG100, WG130, and WG131 transmissions used in heavy-duty industrial vehicles. It also fits select WG180 and WG200 models where the sump plug configuration matches. For proper installation, always replace the 4108306173: GASKET simultaneously to ensure a leak-proof seal. The 0636302056: SCREW PLUG serves a similar role in adjacent assemblies, while the 4108301304: BEARING COVER protects nearby rotating elements from debris.
Related Components
| Part Number | Name | Function |
|---|---|---|
| 4108101112 | HOUSING | Main transmission casing |
| 4108201177 | HOUSING | Secondary housing section |
| 0636302056 | SCREW PLUG | Alternate plug variant |
| 4108301304 | BEARING COVER | Protects bearing assembly |
| 4108306173 | GASKET | Seals plug interface |
| 0750110040 | SHAFT SEAL | Prevents shaft leakage |
| 4108102042 | INPUT | Input shaft assembly |
| 4108302099 | PLANET CARRIER | Planetary gear support |
| 4108302007 | BEARINGSHEET | Bearing shim set |
| 0635332196 | BALL BEARING | Rotational support |
