Overview
The ZF 4656.056.106 6 WG 160 Powershift Transmission Assembly | Complete Unit (SKU: 4656.056.106) is a fully assembled, drop-in replacement for the WG 160 series. This complete unit integrates the main gear cluster, clutch packs, and hydraulic control system into a single, pre-tested assembly. It sits directly between the engine bell housing and the final drive, serving as the central power distribution module for heavy-duty off-highway vehicles. As a complete assembly, it eliminates the need for piecemeal rebuilding, reducing downtime in the field. The unit is designed to interface precisely with the TRANSMISSION HOUSING and the HOUS.FRONT SECT to ensure proper alignment of internal shafts.
Symptoms of Failure
- Delayed or harsh gear engagement: When the internal clutch packs or hydraulic seals degrade, operators experience a noticeable lag or a jarring shift when moving from neutral to forward or reverse. This often indicates internal pressure loss within the assembly.
- Oil leaks at the rear adapter interface: Worn gaskets or cracks in the main casing can cause fluid to seep from the joint between the assembly and the HOUSING REAR PART. Look for puddles of ATF under the transmission bell housing.
- Intermittent power loss under load: As the unit wears, the torque converter or planetary gears may slip, causing the vehicle to lose pulling power when climbing grades or hauling heavy loads. This is often accompanied by a whining noise from the HOUSING REAR SECTION.
- Contaminated transmission fluid: Metallic particles or dark, burnt-smelling fluid in the sump indicate internal wear of the clutch discs or bearings, signaling that the complete unit requires immediate replacement.
Technical Specifications
| Parameter | Value |
|---|---|
| Part Number / SKU | 4656.056.106 |
| Assembly Type | Complete Powershift Unit (6 WG 160) |
| Dry Weight (approx.) | 185 kg (408 lbs) |
| Overall Length | 720 mm |
| Overall Width | 480 mm |
| Overall Height | 510 mm |
| Housing Material | High-strength cast iron (GGG-40) |
| OEM Reference | ZF 4656.056.106 |
| Torque Capacity | 1,600 Nm (1,180 lb-ft) |
| Fluid Capacity | 22 liters (5.8 gallons) |
Compatibility
This complete assembly is engineered specifically for the ZF WG 160 series of powershift transmissions. While it is dimensionally compatible with the WG 180 and WG 200 series in terms of bell housing bolt patterns, the internal gear ratios and clutch pack configurations are unique to the 6-speed WG 160 variant. It is not recommended for use in the WG 120 or WG 250 series without verifying the input shaft spline count and overall length. Always confirm the vehicle’s original transmission tag before installation.
Related Components
| Part Number | Name | Function |
|---|---|---|
| 4656101056 | TRANSMISSION HOUSING | Main structural casing for gear train |
| 4656201075 | HOUS.FRONT SECT | Front section housing input shaft |
| 4656201077 | HOUSING REAR PART | Rear section supporting output flange |
| 4656298049 | HOUSING REAR SECTION | Adapter housing for PTO mounting |
| 0631306816 | CYLINDRICAL PIN | Alignment pin for housing dowels |
| 4656301148 | FIXING PLATE | Secures clutch pack retaining ring |
| 0636100817 | CAP SCREW | M12 bolt for housing fastening |
| 4656301016 | SCREEN SHEET | Fine mesh filter for oil sump |
| 4656301017 | SCREEN SHEET | Coarse mesh pre-filter |
| 0636100803 | CAP SCREW | M10 bolt for valve body cover |
