Overview
The ZF 4661.004.048 4 WG 94 Powershift Transmission Assembly is a complete, factory-sealed unit designed for heavy-duty off-highway machinery. This assembly integrates the main gear cluster, clutch packs, and hydraulic control elements into a single drop-in replacement package. As the core rotating assembly for the WG 94 series, it manages torque distribution across four forward and reverse speeds. The SKU 4661.004.048 is precision-balanced to OEM tolerances and replaces the need for individual component rebuilding. This unit sits directly between the torque converter and the output flange, interfacing with the TRANSMISSION HOUSING and the HOUSING II to form a sealed driveline.
Symptoms of Failure
- Delayed or harsh engagement: When the 4661.004.048 assembly loses internal seal integrity, you will notice a 2-3 second lag when shifting from neutral to forward or reverse, followed by a jarring engagement.
- Intermittent gear slipping under load: Worn clutch discs within the unit cause the transmission to momentarily lose power during uphill grading or heavy pulling, often accompanied by a burning oil smell.
- Metallic grinding noise from the bell housing: Bearing fatigue inside the assembly produces a low-frequency rumble that intensifies as the machine warms up, indicating imminent planetary gear failure.
- Hydraulic oil contamination with bronze particles: If you find glitter-like debris in the filter or sump magnet, the 4661.004.048 thrust washers are degrading, requiring immediate replacement of the complete unit.
Technical Specifications
| Parameter | Value |
|---|---|
| OEM Part Number | 4661.004.048 |
| Assembly Type | Complete Powershift Unit (4 WG 94) |
| Dry Weight | 98 kg (216 lbs) |
| Overall Length | 620 mm |
| Maximum Diameter | 380 mm |
| Housing Material | High-Grade Cast Iron (GGG-40) |
| Clutch Disc Material | Sintered Bronze on Steel |
| Max Input Torque | 1,200 Nm |
| Oil Capacity (Internal) | 4.5 liters |
| OEM Reference | ZF 4661.004.048 / 4 WG 94 |
Compatibility
This 4661.004.048 assembly is engineered exclusively for the ZF WG 94 series of powershift transmissions. It is a direct fit for the WG94, WG98, and WG100 models commonly found in telescopic handlers, wheel loaders, and rough-terrain forklifts. The unit is not compatible with the WG180 or WG200 series due to differences in input shaft spline count and clutch pack stack height. When installing, always pair this assembly with a new CYLINDRICAL PIN for alignment and a fresh TUBE for the internal lubrication circuit to prevent oil starvation.
Related Components
| Part Number | Name | Function |
|---|---|---|
| 4661101023 | TRANSMISSION HOUSING | Outer casing that encloses the 4661.004.048 assembly |
| 4661301051 | HOUSING II | Rear cover housing supporting the output shaft bearing |
| 4661301093 | TUBE | Lubrication oil feed tube for the clutch packs |
| 0631306174 | CYLINDRICAL PIN | Dowel pin for precise housing-to-assembly alignment |
| 0769123894 | TYPE PLATE | Identification plate riveted to the housing |
| 0750100022 | SCREW PLUG | Magnetic drain plug for the sump |
| 0636302602 | SCREW PLUG | Hexagonal fill plug with sealing washer |
| 0634100633 | O-RING | Seal for the tube-to-housing connection |
| 4661301029 | NOZZLE | Oil spray nozzle for planetary gear lubrication |
| 4661301027 | NOZZLE | Secondary oil nozzle for clutch cooling |
