Overview
The ZF 4651.004.016 4 WG 100(400) Powershift Transmission Assembly is a complete, factory-matched unit engineered for heavy-duty off-highway applications. This assembly integrates the clutch pack, planetary gear sets, and hydraulic control elements into a single, ready-to-install package. As the core power transfer module within the WG 100 Series, it replaces the entire rotating assembly to restore original shift quality and torque capacity. The SKU 4651.004.016 is a direct OEM-spec replacement, ensuring seamless integration with existing driveline components. When rebuilding, always pair this assembly with a new TRANSMISSION HOUSING to guarantee correct alignment and sealing.
Symptoms of Failure
- Delayed or harsh engagement: When the internal clutch discs or seals wear, you will notice a pronounced lag when shifting from neutral to forward or reverse, followed by a jarring engagement. This is a classic sign that the 4651.004.016 assembly requires replacement.
- Intermittent gear slipping under load: A worn powershift assembly loses hydraulic clamping force, causing the transmission to slip during heavy pulling or incline operation. This symptom often escalates rapidly if ignored.
- Contaminated transmission fluid with metallic debris: Friction material shedding from the clutch packs within the assembly will produce fine metallic particles in the oil. If you find glitter or sludge during routine fluid changes, the internal assembly is failing.
- Complete loss of drive in one range: A fractured planetary carrier or broken snap ring inside the assembly will cause a total loss of power in a specific gear range, requiring immediate unit replacement.
Technical Specifications
| Parameter | Value |
|---|---|
| Assembly Weight (approx.) | 68 kg (150 lbs) |
| Overall Length | 485 mm |
| Overall Diameter | 320 mm |
| Primary Material | Heat-treated alloy steel / Sintered bronze |
| OEM Reference | ZF 4651.004.016 |
| Torque Capacity (max) | 400 Nm |
| Wet Clutch Disc Count | 6 friction / 6 steel |
Compatibility
This complete unit is specifically designed for the ZF WG 100 series powershift transmissions. It is a direct fit for the 4 WG 100(400) variant. While the internal architecture shares design principles with larger WG series models, the 4651.004.016 is not interchangeable with the WG 180 or WG 200 assemblies due to differences in shaft diameter and clutch pack stack height. Always verify your transmission model tag before ordering. For related sealing components, consider the O-RING and the HOUSING to complete your rebuild kit. Additionally, the HOUSING is a critical companion part for this assembly.
Related Components
| Part Number | Name | Function |
|---|---|---|
| 4651101009 | TRANSMISSION HOUSING | Main structural casing for the assembly |
| 4651301025 | HOUSING | Intermediate housing for clutch support |
| 0634303928 | O-RING | Static seal between housing sections |
| 4651301031 | HOUSING | Rear housing for output shaft support |
| 4651203002 | SCREEN SHEET | Fine mesh filter for hydraulic circuit |
| 4651303005 | SCREEN SHEET | Secondary filter screen for oil return |
| 0636101032 | CAP SCREW | Fastener for housing assembly |
| 0630361028 | SEALING CAP | Closure for hydraulic test ports |
| 4475280060 | SCREW PLUG | Threaded plug for drain/fill holes |
| 0634303312 | O-RING | Seal for screw plug applications |
