Overview
The ZF 4660.001.025 WG 92 S 4 Powershift Transmission Assembly | Complete Unit is a fully assembled drop-in solution designed for heavy-duty off-highway applications. This complete unit integrates the main gear cluster, clutch packs, and hydraulic control components into a single, ready-to-install package. As a core element of the WG 92 Series, this assembly manages torque distribution across four forward and reverse speeds, ensuring smooth power delivery under extreme loads. The SKU 4660.001.025 is the definitive identifier for this specific complete unit, which is often paired with the 4660101011: TRANSMISSION HOUSING to form the primary structural enclosure. For proper sealing and identification, technicians frequently install the 0769123894: TYPE PLATE alongside this unit during rebuilds.
Symptoms of Failure
- Delayed or harsh engagement: When the complete unit wears, operators often report a noticeable lag between shifting and gear engagement, or a jarring “clunk” during direction changes. This is a classic sign of internal clutch pack degradation within the assembly.
- Loss of power under load: A failing unit may cause the vehicle to struggle on inclines or under heavy payloads, as internal hydraulic pressure drops and clutches begin to slip. This symptom is frequently searched as “ZF powershift slipping under load.”
- Contaminated transmission fluid: Metal shavings or dark, burnt-smelling fluid in the sump indicates advanced wear inside the assembly. This often accompanies damage to the 0631306174: CYLINDRICAL PIN which can fracture and circulate debris.
- External oil seepage at housing joints: Cracks or warpage in the main casing can cause fluid to weep around the mating surfaces of the 4660301018: HOUSING, leading to low fluid levels and eventual overheating.
Technical Specifications
| Parameter | Specification |
|---|---|
| OEM Reference | ZF 4660.001.025 |
| Assembly Type | Complete Powershift Unit (WG 92 S 4) |
| Dry Weight (approx.) | 185 kg (408 lbs) |
| Overall Length | 720 mm |
| Overall Width | 480 mm |
| Overall Height | 510 mm |
| Primary Material | Cast Iron Housing with Steel Gears |
| Input Spline Count | 14-tooth, 2.5″ pitch |
| Max Input Torque | 1,200 Nm |
| Fluid Capacity (unit only) | 12.5 liters |
Compatibility
This complete unit is engineered for the ZF WG 92 Series powershift transmission family. It is directly compatible with the following ZF models: WG92, WG120, WG150, WG180, and WG200. These transmissions are commonly found in telescopic handlers, wheel loaders, and rough-terrain forklifts from manufacturers such as JCB, Manitou, and Caterpillar. The assembly also interfaces with the 4660221012: SUCTION TUBE for fluid pickup and requires the 0634100317: O-RING for sealing the hydraulic circuit. For mounting, use the 0636103273: CAP SCREW and 0750100022: SCREW PLUG to secure the assembly to the bell housing.
Related Components
| Part Number | Name | Function |
|---|---|---|
| 4660101011 | TRANSMISSION HOUSING | Main structural casing for gear support |
| 4660301018 | HOUSING | Secondary cover for clutch access |
| 0631306174 | CYLINDRICAL PIN | Alignment dowel for precise assembly |
| 0769123894 | TYPE PLATE | Identification tag with serial number |
| 4660221012 | SUCTION TUBE | Fluid intake line from sump |
| 0634100317 | O-RING | Hydraulic seal for pressure circuits |
| 0636103273 | CAP SCREW | High-tensile fastener for housing |
| 0750100022 | SCREW PLUG | Drain/fill port closure |
| 4660101804 | TRANSMISSION HOUSING | Alternate housing variant for WG92 |
| 4660301008 | HOUSING | Alternate cover for different clutch pack |
