Overview
The ZF 0501.315.787 SCREW PLUG is a precision-engineered sealing component designed for the WG100, WG130, and WG131 transmission series. This OEM genuine part functions as a threaded closure within the valve body or housing assembly, preventing fluid bypass and maintaining critical hydraulic pressure. The SKU 0501.315.787 is manufactured to exact ZF tolerances, ensuring a leak-proof seal at the interface between the 4108101140 HOUSING and the internal oil galleries. Without this plug, the transmission cannot sustain the necessary lubrication flow for planetary gear sets and clutch packs.
Symptoms of Failure
- External oil seepage around the housing: A worn or cross-threaded 0501.315.787 screw plug allows ATF to weep past the threads, leaving visible drips under the bell housing.
- Erratic shift timing or gear slipping: When the plug fails to seal, hydraulic pressure drops in the control circuit, causing delayed engagement or clutch chatter during acceleration.
- Contaminated transmission fluid: A loose plug can allow debris ingress into the valve body, leading to premature wear of the 0501211694 MOTOR and associated solenoids.
- Audible hissing or whining from the transmission: Air ingestion through a compromised screw plug creates cavitation noise, particularly under load in WG100 series units.
Technical Specifications
| Parameter | Value |
|---|---|
| Part Number | 0501.315.787 |
| Thread Size | M14 x 1.5 (estimated) |
| Overall Length | 18 mm |
| Head Diameter | 19 mm hex |
| Material | Steel, zinc-plated |
| Sealing Type | Copper washer / O-ring |
| Weight | 12 g |
| OEM Reference | ZF 0501.315.787 |
Compatibility
This screw plug is specifically validated for the following ZF transmission models: WG100, WG130, and WG131. It is also compatible with the WG180 and WG200 series when used in the same housing bore. The plug mates directly with the 0501314793 COVER and the 0501314799 BUSH in the lower valve body section. Always verify thread pitch before installation to avoid cross-threading in the housing.
Related Components
| Part Number | Name | Function |
|---|---|---|
| 4108101140 | HOUSING | Main transmission casing |
| 0501211694 | MOTOR | Electric shift actuator |
| 0501314793 | COVER | Valve body access cover |
| 0501314799 | BUSH | Guide bushing for shaft |
| 0735370299 | TAPERED ROLLER BEARING | Radial/axial load support |
| 0501317874 | HOUSING | Secondary housing section |
| 0501317875 | ROLLER | Needle roller for clutch |
| 0501209497 | PISTON | Clutch apply piston |
| 0501317876 | COMPRESSION SPRING | Return spring for piston |
| 0501314823 | BUSH | Wear sleeve bushing |
