Overview
The ZF 4651.003.012 3 WG 100(400) Powershift Transmission Assembly represents a complete, fully assembled unit engineered for heavy-duty off-highway applications. This assembly integrates the clutch pack, planetary gearsets, and hydraulic control elements into a single, ready-to-install module. As a core component of the WG 100 series, it manages torque distribution and gear ratio changes under load, ensuring smooth power delivery in wheel loaders, dozers, and industrial vehicles. The SKU 4651.003.012 is a direct replacement for OEM units, eliminating the need for partial rebuilds. It sits centrally within the drivetrain, connecting the torque converter to the output shaft, and is sealed by the TRANSMISSION HOUSING which provides structural integrity and oil containment.
Symptoms of Failure
- Delayed or harsh gear engagement: When the 4651.003.012 assembly wears, hydraulic pressure drops, causing noticeable lag or jarring shifts between forward and reverse.
- Internal oil leaks and low fluid pressure: Worn seals within the assembly lead to external drips or internal cross-leaks, often indicated by a burnt smell or erratic shifting.
- Torque converter shudder under load: A vibrating or shuddering sensation during acceleration signals clutch plate wear or damaged pistons inside the assembly.
- Complete loss of drive in one range: If the planetary gearset fails, the machine may move in forward but not reverse, or vice versa, requiring immediate replacement of the complete unit.
Technical Specifications
| Parameter | Value |
|---|---|
| Part Number / SKU | 4651.003.012 |
| Assembly Type | 3 WG 100(400) Powershift |
| Overall Length | ~420 mm |
| Overall Width | ~350 mm |
| Dry Weight | ~85 kg |
| Housing Material | High-strength cast iron |
| OEM Reference | ZF 4651.003.012 |
| Max Input Torque | 400 Nm |
| Seal Type | Viton O-rings (see O-RING) |
Compatibility
This complete unit is specifically designed for the ZF WG 100 series transmissions, including models WG 100, WG 101, and WG 102 used in compact wheel loaders and telehandlers. It is not directly compatible with larger WG 180 or WG 200 series without modification, as those require different clutch capacities and housing dimensions. For proper installation, ensure the HOUSING and HOUSING components are matched to this assembly. Always verify your transmission serial number before ordering.
Related Components
| Part Number | Name | Function |
|---|---|---|
| 4651101009 | TRANSMISSION HOUSING | Encloses and supports the assembly |
| 4651301025 | HOUSING | Rear cover for clutch pack access |
| 0634303928 | O-RING | Seals housing joints against leaks |
| 4651301031 | HOUSING | Front housing for pump mounting |
| 4651203002 | SCREEN SHEET | Filters debris from hydraulic oil |
| 4651303005 | SCREEN SHEET | Secondary filtration element |
| 0636101032 | CAP SCREW | Secures housing to transmission |
| 0630361028 | SEALING CAP | Closes unused ports |
| 4475280060 | SCREW PLUG | Drain or fill plug |
| 0634303312 | O-RING | Seals screw plug connections |
