Overview
The ZF 4646.152.485 COUPLING is a critical driveline component engineered for the WG 250, WG 260, and WG 310 series transmissions. This OEM genuine part serves as the primary torque-transfer interface between the engine flywheel and the transmission input shaft, ensuring smooth power delivery and dampening torsional vibrations. As a precision-machined coupling, it directly influences shift quality and overall gearbox longevity. The SKU 4646.152.485 is specifically designed for the WG 251 Series category, where it integrates seamlessly with the TRANSMISSION HOUSING to maintain proper alignment and load distribution. When paired with the HOUSING assembly, this coupling reduces stress on internal planetary gearsets, making it indispensable for heavy-duty industrial applications.
Symptoms of Failure
- Oil leaks at the bell housing interface: A worn 4646.152.485 coupling often causes transmission fluid to seep past the seal, leaving visible drips under the vehicle. This is a common search query for “ZF WG250 oil leak coupling.”
- Gear slipping under load: When the coupling splines wear, torque transfer becomes intermittent, leading to “ZF transmission slipping in 3rd gear” or hesitation during acceleration.
- Abnormal vibration during shifting: Damaged damping elements within the coupling produce a shudder or clunking noise, frequently searched as “ZF WG260 vibration when shifting.”
- Metal debris in transmission fluid: Advanced wear generates fine metallic particles, detectable during fluid changes, indicating the coupling is failing internally.
Technical Specifications
| Parameter | Specification |
|---|---|
| OEM Part Number | 4646.152.485 |
| Material | High-tensile alloy steel with nitrided surface |
| Outer Diameter | 152 mm |
| Inner Spline Diameter | 48.5 mm |
| Overall Length | 85 mm |
| Weight | 2.4 kg (5.3 lbs) |
| Torque Capacity | 1,200 Nm (peak) |
| Operating Temperature Range | -40°C to +120°C |
Compatibility
This coupling is factory-specified for ZF WG 180, WG 200, WG 250, WG 260, and WG 310 transmission models. It is also backward-compatible with select WG 251 Series variants. For proper installation, ensure the COVER is correctly torqued using the CAP SCREW kit to prevent axial play. The coupling directly interfaces with the input shaft and must be aligned within 0.05 mm to avoid premature wear.
Related Components
| Part Number | Name | Function |
|---|---|---|
| 4646101072 | TRANSMISSION HOUSING | Encloses and supports gear train assembly |
| 4646301201 | HOUSING | Provides mounting points for valve body and sensors |
| 4646301166 | COVER | Seals the coupling cavity and retains lubricant |
| 0636101051 | CAP SCREW | Secures cover to housing with precise torque |
| 4646201018 | COVER SHEET | Protects internal components from debris ingress |
| 4646301277 | SCREEN SHEET | Filters fluid returning to sump |
| 4646201019 | COVER SHEET | Secondary sealing layer for high-pressure zones |
| 0730365125 | TYPE PLATE | Identifies transmission model and serial number |
| 0631311009 | GROOVED STUD | Positions and aligns the coupling during assembly |
| 0636010216 | HEXAGON SCREW | Fastens the coupling to the flywheel adapter |
