Overview
The ZF 4661.004.007 4 WG 94 Powershift Transmission Assembly is a complete, factory-grade unit designed for heavy-duty off-highway machinery. This assembly integrates the core hydraulic and mechanical components of the WG 94 series, serving as the primary power distribution hub within the transmission system. The SKU 4661.004.007 replaces the need for piecemeal repairs by providing a fully assembled unit, ensuring precise alignment of internal clutches, shafts, and valve bodies. It is typically mounted between the engine bell housing and the final drive, converting torque into controlled forward and reverse motion for wheel loaders and graders.
Symptoms of Failure
- Delayed or harsh gear engagement: When the 4661.004.007 assembly wears, operators often experience a noticeable lag between shifting and actual gear engagement, followed by a jarring clunk. This indicates internal clutch pack wear or hydraulic pressure loss within the unit.
- Chronic transmission overheating: A failing assembly can cause excessive friction, leading to fluid temperatures exceeding 120°C (248°F). This is a common long-tail search query for “ZF WG94 overheating causes” and often points to worn seals or damaged valve bodies inside the unit.
- Intermittent power loss under load: Operators may notice the machine losing traction or speed when pushing heavy loads, even with the engine at full RPM. This symptom, searched as “transmission slipping under load ZF,” suggests internal leakage past the piston rings or a compromised torque converter section within the assembly.
- External fluid seepage near the bell housing: Oil leaks originating from the joint between the transmission and engine are a direct sign of a failing gasket or cracked housing within the 4661.004.007 unit.
Technical Specifications
| Specification | Detail |
|---|---|
| Part Number | 4661.004.007 |
| Assembly Type | Complete Powershift Unit (4 WG 94) |
| Dry Weight (approx.) | 185 kg (408 lbs) |
| Overall Length | 620 mm |
| Overall Width | 480 mm |
| Overall Height | 510 mm |
| Primary Material | High-tensile cast iron housing with hardened steel gears |
| OEM Reference | ZF Friedrichshafen AG |
| Fluid Capacity (assembly) | 14.5 liters (SAE 10W or Dexron III) |
Compatibility
This 4661.004.007 assembly is engineered for the ZF WG 94 series of powershift transmissions. It is directly compatible with the following models: WG94, WG180, and WG200 (when configured with the 4-speed forward/3-speed reverse layout). It also fits select variants of the WG120 and WG150 series used in compact loaders. Always verify the serial number plate on your existing unit before installation, as minor variations exist between early and late production runs.
During installation, this assembly integrates directly with the TRANSMISSION HOUSING (4661101019) and the HOUSING II (4661301051) to form the main structural shell. The internal lubrication circuit relies on the TUBE (4661301093) for oil distribution, while the CYLINDRICAL PIN (0631306174) ensures precise alignment of the shift fork assembly during reassembly.
Related Components
| Part Number | Name | Function |
|---|---|---|
| 4661101019 | TRANSMISSION HOUSING | Main structural casing for the gear train |
| 4661301051 | HOUSING II | Secondary housing covering the clutch pack area |
| 4661301093 | TUBE | Oil delivery tube for internal lubrication |
| 0631306174 | CYLINDRICAL PIN | Alignment pin for shift mechanism |
| 0769123894 | TYPE PLATE | Identification plate with serial number |
| 0750100022 | SCREW PLUG | Sealing plug for fluid drain port |
| 0636302602 | SCREW PLUG | Magnetic plug for debris collection |
| 0634100633 | O-RING | Hydraulic seal for pressure lines |
| 4661301029 | NOZZLE | Lubrication jet for planetary gears |
| 4661301027 | NOZZLE | Secondary lubrication jet for clutch cooling |
