Overview
The ZF 0636.101.138 CAP SCREW is a critical fastening component engineered for the WG150, WG200, and WG201 series transmissions. This OEM genuine part secures the transmission housing assembly, ensuring that internal components remain precisely aligned under high-torque loads. The SKU 0636.101.138 is specifically designed to withstand the vibrational stresses and thermal expansion common in heavy-duty industrial applications. When installed correctly, this cap screw maintains the structural integrity of the gearbox, preventing unwanted movement between the TRANSMISSION HOUSING and adjacent subassemblies.
Symptoms of Failure
- Oil seepage at housing joints: A loose or fatigued cap screw can cause the transmission housing to separate slightly, leading to fluid migration. Search for “ZF WG200 oil leak at housing bolt” to identify this issue.
- Abnormal gear whine or vibration: When the 0636.101.138 loses clamping force, internal gear alignment shifts, producing audible noise during operation. This is a common symptom for “WG150 transmission vibration under load.”
- Intermittent gear engagement difficulty: A failing cap screw allows micro-movement in the housing, which can cause shift forks to misalign. Look for “WG201 hard shifting when warm” as a related long-tail query.
- Visible corrosion or thread galling: Exposure to transmission fluid and heat can degrade the screw’s surface, making removal difficult during service intervals.
Technical Specifications
| Specification | Value |
|---|---|
| Part Number | 0636.101.138 |
| Thread Size | M10 x 1.5 (estimated) |
| Length | 45 mm (estimated) |
| Head Type | Hexagon socket cap |
| Material | Alloy steel, 10.9 grade |
| Surface Finish | Zinc-plated, yellow passivated |
| Weight | 0.04 kg (estimated) |
| OEM Reference | ZF 0636.101.138 |
Compatibility
This cap screw is a direct OEM replacement for the following ZF transmission models: WG 150 Series, WG 200 Series, WG 201 Series, and WG 65 Series. It is commonly used in conjunction with the HEXAGON SCREW (0636011038) for securing the oil pan, the HEXAGON SCREW (0636011118) for valve body attachment, and the HEXAGON SCREW (0636016015) for clutch housing retention. Always verify thread pitch and length against your specific transmission serial number before installation.
Related Components
| Part Number | Name | Function |
|---|---|---|
| 4616101059 | TRANSMISSION HOUSING | Main structural casing for gear assembly |
| 0636011038 | HEXAGON SCREW | Fastens oil pan to housing |
| 0636011118 | HEXAGON SCREW | Secures valve body assembly |
| 0636016015 | HEXAGON SCREW | Attaches clutch housing components |
| 0631306085 | CYLINDRICAL PIN | Alignment dowel for housing mating |
| 0634313118 | O-RING | Seals fluid passages in valve body |
| 0636304019 | SCREW PLUG | Closes oil drain or fill ports |
| 0634801152 | SEALING RING | Prevents leakage at plug interfaces |
| 0732611049 | FILTER INSERT | Traps debris in hydraulic circuit |
| 0634303718 | O-RING | Seals filter housing connection |
