Overview
The ZF 4661.001.017 4 WG 90 Powershift Transmission Assembly represents a complete, factory-grade replacement unit designed for heavy-duty off-highway machinery. This fully assembled gearbox integrates the planetary gear set, clutch packs, and hydraulic control system into a single drop-in solution. Identified by SKU 4661.001.017, this unit sits at the core of the drivetrain, converting engine torque into controlled power for wheel loaders, forklifts, and industrial tractors. When rebuilding a WG 90 series transmission, this assembly is often paired with the 4661101020: TRANSMISSION HOUSING to ensure proper alignment and sealing of the internal components.
Symptoms of Failure
- Delayed engagement or gear slipping under load: Worn clutch discs or degraded seals within the assembly cause the transmission to hesitate before moving or lose torque during operation.
- Hydraulic oil contamination with metallic debris: Internal gear wear or bearing failure produces fine metal particles in the fluid, visible during oil changes or filter inspections.
- Erratic shifting or harsh engagement: A failing valve body or damaged piston seals lead to unpredictable shift points and jarring gear changes.
- External oil leaks near the bell housing: Cracks in the 4661301046: HOUSING II or degraded gaskets allow transmission fluid to escape, reducing lubrication and causing overheating.
Technical Specifications
| Specification | Value |
|---|---|
| Assembly Weight (Dry) | 185 kg (408 lbs) |
| Overall Length | 620 mm |
| Overall Width | 480 mm |
| Overall Height | 510 mm |
| Housing Material | High-Grade Cast Iron (GGG-40) |
| OEM Reference | ZF 4661.001.017 |
| Torque Capacity | 900 Nm (664 lb-ft) |
| Fluid Capacity | 14.5 Liters |
Compatibility
This complete assembly is engineered specifically for the ZF WG 90 series powershift transmissions. It is directly compatible with the following models: WG 90, WG 98, and WG 100. The unit also fits select variants of the WG 120 series when used with the correct 4661301093: TUBE for oil routing. For proper installation, ensure the 0631306174: CYLINDRICAL PIN is aligned correctly to prevent misalignment of the clutch housing.
Related Components
| Part Number | Name | Function |
|---|---|---|
| 4661101020 | TRANSMISSION HOUSING | Encloses and supports the gear train and clutch assembly |
| 4661301046 | HOUSING II | Rear housing section containing the output shaft bearings |
| 4661301093 | TUBE | Oil supply tube directing hydraulic fluid to clutch packs |
| 0631306174 | CYLINDRICAL PIN | Alignment pin for precise housing mating |
| 0769123894 | TYPE PLATE | Identification plate with serial number and model info |
| 0750100022 | SCREW PLUG | Seals the oil drain port |
| 0636302602 | SCREW PLUG | Seals the fill port |
| 0634100633 | O-RING | Provides leak-proof seal between housing sections |
| 4661301041 | NOZZLE | Sprays lubricating oil onto the ring gear |
| 4661301038 | NOZZLE | Sprays lubricating oil onto the sun gear |
