Overview
The ZF 4657.026.118 6 WG 190 Powershift Transmission Assembly | Complete Unit is a fully assembled, drop-in ready drivetrain component engineered for heavy-duty off-highway machinery. This complete unit integrates the planetary gear set, clutch packs, and hydraulic control system within a robust casing, serving as the core power distribution hub for articulated dump trucks, wheel loaders, and graders. The SKU 4657.026.118 designates a factory-matched assembly that eliminates the need for piecemeal rebuilding, ensuring precise gear engagement under high torque loads. It sits as the central assembly between the torque converter and the final drive, with the TRANSMISSION HOUSING providing the structural foundation for all internal rotating elements.
Symptoms of Failure
- Erratic gear engagement and clutch shudder: When the complete unit loses hydraulic pressure integrity, operators experience delayed or harsh shifting, particularly when transitioning between forward and reverse ranges.
- Torque converter stall or overheating: A failing assembly often causes the transmission to overheat rapidly under load, indicated by high temperature gauges and a burnt oil smell, due to internal seal degradation.
- Oil contamination with metallic debris: Worn bearings or planetary gear spalling within the unit will produce fine metal particles in the fluid, visible during oil changes as a glittering or sludgy residue.
- Complete loss of forward or reverse drive: Advanced failure of the clutch drum or sun gear results in a no-move condition, requiring immediate replacement of the entire assembly rather than individual components.
Technical Specifications
| Parameter | Value |
|---|---|
| Part Number | 4657.026.118 |
| Assembly Type | Complete Powershift Unit (6 WG 190) |
| Dry Weight (approx.) | 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 4657.026.118 |
| Torque Capacity | 1,900 Nm (1,401 lb-ft) |
| Number of Speeds | 6 forward / 3 reverse |
Compatibility
This complete unit is specifically designed for the ZF WG 190 series of powershift transmissions. It is directly compatible with the WG 190, WG 191, and WG 192 variants used in construction and mining equipment. While the assembly is optimized for the WG 190 platform, it can also be adapted to the WG 180 and WG 200 series with minor modifications to the bell housing interface. The unit integrates seamlessly with the HOUS.FRONT SECT and the HOUSING REAR PART, which must be inspected for wear during installation. For extended rebuilds, the HOUSING REAR SECTION provides additional structural support for the output shaft.
Related Components
| Part Number | Name | Function |
|---|---|---|
| 4657101082 | TRANSMISSION HOUSING | Main structural casing for gear train |
| 4657201166 | HOUS.FRONT SECT | Front section housing torque converter |
| 4657201170 | HOUSING REAR PART | Rear section for output shaft support |
| 4657298102 | HOUSING REAR SECTION | Extended rear housing for PTO mount |
| 0631306816 | CYLINDRICAL PIN | Alignment pin for housing mating |
| 0636100801 | CAP SCREW | Fastener for housing flanges |
| 4656301148 | FIXING PLATE | Locks clutch pack in position |
| 4657301032 | SCREEN SHEET | Fine mesh filter for oil circuit |
| 4657301033 | SCREEN SHEET | Coarse mesh pre-filter for sump |
| 0636100803 | CAP SCREW | High-tensile bolt for clutch drum |
