Overview
The ZF 0636.102.885 CAP SCREW is a critical fastening component engineered specifically for the WG100, WG130, and WG131 transmission series. This OEM genuine part secures internal housing assemblies and pressure plates within the transmission casing, ensuring that high-torque loads are distributed evenly without fastener fatigue. The SKU 0636.102.885 is precision-machined to maintain clamping force under extreme thermal cycling and vibration. It is commonly installed alongside the 2094101017: TRANSMISSION HOUSING and the 2094301069: HOUSING, where it anchors structural components that guide gear alignment and fluid flow.
Symptoms of Failure
- Transmission oil seepage around bolt heads: A loose or fatigued cap screw can compromise the seal between the 2094298054: HOUSING and the main case, leading to visible fluid weeping.
- Abnormal gear rattle or clunking during shifts: When the cap screw loses preload, internal clearances increase, causing misalignment and audible metallic contact.
- Intermittent loss of hydraulic pressure: A fractured cap screw can allow the valve body or accumulator housing to shift, resulting in delayed engagement or slipping.
- Vibration at specific RPM ranges: Worn threads or a stretched shank reduce rigidity, transmitting driveline harmonics into the cab or chassis.
Technical Specifications
| Parameter | Value |
|---|---|
| Part Number | 0636.102.885 |
| Thread Size | M10 x 1.5 (estimated) |
| Overall Length | 35 mm |
| Head Type | Hexagon socket (Allen) |
| Material | High-tensile alloy steel, zinc-plated |
| Weight | ~18 g |
| OEM Reference | ZF 0636.102.885 |
| Grade | 10.9 (estimated) |
Compatibility
This cap screw is factory-specified for the ZF WG100, WG130, and WG131 off-highway transmissions. It is also used in select WG180 and WG200 variants where the housing bolt pattern matches the M10 thread pitch. Always verify thread engagement depth when replacing fasteners in the 0636302008: SCREW PLUG port area, as cross-threading can damage the housing bore. For complete assembly integrity, pair this screw with a new 0634801165: SEALING RING and inspect the 0635460022: BALL check valve if present in the same circuit.
Related Components
| Part Number | Name | Function |
|---|---|---|
| 2094101017 | TRANSMISSION HOUSING | Main structural casing for gear sets |
| 2094301069 | HOUSING | Intermediate support housing for shafts |
| 2094298054 | HOUSING | Rear housing with bearing bores |
| 0636302008 | SCREW PLUG | Seals oil passages and inspection ports |
| 0634801165 | SEALING RING | Prevents fluid bypass at fastener joints |
| 0635460022 | BALL | Check valve ball for pressure regulation |
| 2094301071 | COVER | Access cover for clutch pack service |
| 2094301030 | GASKET | Compression seal between housing faces |
| 0750111371 | SHAFT SEAL | Dynamic seal for output shaft |
| 0634303085 | O-RING | Static seal for hydraulic ports |
