Overview
The ZF 4661.004.034 4 WG 94 Powershift Transmission Assembly is a complete, fully assembled unit designed for heavy-duty off-highway applications. This assembly serves as the core power transfer module within the WG 94 series, integrating the main drive gear set, clutch packs, and hydraulic control circuits into a single, ready-to-install package. The SKU 4661.004.034 identifies a factory-matched assembly that eliminates the need for individual component shimming and calibration. It sits directly between the torque converter and the output driveline, managing gear ratio changes under full load. For proper sealing and structural integrity, this unit mates with the 4661101028: TRANSMISSION HOUSING and the 4661301049: HOUSING II, which together form the rigid enclosure for all rotating elements.
Symptoms of Failure
- Delayed or harsh engagement: When the internal clutch piston seals degrade, you may experience a noticeable lag when shifting from neutral to forward or reverse, followed by a jarring engagement. This often points to wear inside the 4661.004.034 assembly.
- Intermittent gear slippage under load: A failing unit will lose torque transfer capability, causing the machine to rev higher without proportional acceleration, especially on inclines or during heavy digging cycles.
- Contaminated transmission fluid with metallic debris: Worn bearings or clutch plates within the assembly shed fine metal particles into the oil, visible during routine drain intervals or on the magnetic sump plug.
- Audible whining or grinding from the bell housing: As internal bushings wear, the gear train produces a high-pitched noise that increases with engine RPM, indicating imminent mechanical failure of the complete unit.
Technical Specifications
| Parameter | Value |
|---|---|
| Part Number (SKU) | 4661.004.034 |
| Assembly Type | Complete Powershift Unit (4 WG 94) |
| Dry Weight (approx.) | 185 kg (408 lbs) |
| Overall Length | 620 mm |
| Overall Width | 410 mm |
| Overall Height | 480 mm |
| Primary Material | Cast Iron Housing with Hardened Steel Gears |
| OEM Reference | ZF 4661.004.034 |
| Torque Capacity (max) | 1,200 Nm (885 lb-ft) |
| Hydraulic Pressure Range | 14–18 bar (203–261 psi) |
Compatibility
This complete unit is engineered specifically for the ZF WG 94 transmission series. It is a direct fit for models including the WG180, WG200, and WG210 powershift transmissions commonly found in wheel loaders, telehandlers, and industrial tractors. The 4661.004.034 assembly is not interchangeable with the WG 100 or WG 120 series due to differences in input shaft spline count and clutch pack stack height. Always verify your transmission model tag before ordering. During installation, the 4661301093: TUBE must be aligned correctly to ensure proper lubrication flow to the upper clutch drums, and the 0631306174: CYLINDRICAL PIN is required for precise dowel alignment between the housing halves.
Related Components
| Part Number | Name | Function |
|---|---|---|
| 4661101028 | TRANSMISSION HOUSING | Main structural enclosure for gear sets |
| 4661301049 | HOUSING II | Rear cover housing for output shaft support |
| 4661301093 | TUBE | Lubrication oil delivery tube to clutch packs |
| 0631306174 | CYLINDRICAL PIN | Alignment dowel for housing mating surfaces |
| 0769123894 | TYPE PLATE | Identification plate with serial number |
| 0750100022 | SCREW PLUG | Magnetic drain plug for oil pan |
| 0636302602 | SCREW PLUG | Pressure test port plug |
| 0634100633 | O-RING | Seal for housing joint faces |
| 4661301029 | NOZZLE | Lubrication jet for planetary gears |
| 4661301027 | NOZZLE | Lubrication jet for clutch drum |
