Overview
The ZF 4657.026.112 6 WG 190 Powershift Transmission Assembly | Complete Unit is a fully assembled, ready-to-install core component designed for heavy-duty industrial drivelines. This complete unit integrates the main gear cluster, clutch packs, and hydraulic control system within a single, robust housing. As the central power transfer module, it replaces the entire worn-out assembly in ZF’s WG 190 series, eliminating the need for piecemeal repairs. The SKU 4657.026.112 denotes a factory-specification unit that directly interfaces with the 4657101082: TRANSMISSION HOUSING to form the primary structural shell. This assembly is the heart of the powershift system, managing torque distribution across six forward gears.
Symptoms of Failure
When the ZF 4657.026.112 assembly degrades, operators typically encounter these specific failure modes:
- Delayed or harsh gear engagement: A noticeable lag when shifting from neutral to drive, often accompanied by a jarring clunk, indicating worn clutch plates or hydraulic pressure loss within the assembly.
- Internal oil leaks pooling under the bell housing: Fluid seeping from the main case joints, often traced back to failed seals between the assembly and the 4657201166: HOUS.FRONT SECT.
- Intermittent power loss under load: The transmission slips or loses torque when climbing grades or hauling heavy payloads, a classic sign of fatigued internal clutches or a failing torque converter lock-up.
- Unusual whining or grinding noises from the center case: Metallic sounds emanating from the main gear area, often linked to bearing failure or debris contamination within the assembly.
Technical Specifications
| Specification | Detail |
|---|---|
| Part Number / SKU | 4657.026.112 |
| Assembly Type | Complete Powershift Unit (6 WG 190) |
| Dry Weight (approx.) | 185 kg (408 lbs) |
| Overall Length | 720 mm |
| Overall Width | 480 mm |
| Overall Height | 560 mm |
| Primary Material | High-strength cast iron with steel internals |
| OEM Reference | ZF 4657.026.112 (Direct Replacement) |
| Bolt Torque Spec (Main Case) | Refer to 0636100801: CAP SCREW spec sheet |
| Rear Seal Interface | Compatible with 4657298102: HOUSING REAR SECTION |
Compatibility
This complete unit is engineered specifically for the ZF WG 190 series of powershift transmissions. It is a direct fit for models including the WG 180, WG 190, and WG 200, where the 6-speed configuration is specified. The assembly is designed to bolt directly to the 4657201170: HOUSING REAR PART and the front section housing. It is commonly found in construction loaders, agricultural tractors, and material handlers from OEMs such as Case, New Holland, and JCB that utilize ZF drivelines. Always verify the serial number of your existing unit against the 4657.026.112 designation to ensure correct spline count and clutch pack configuration.
Related Components
| Part Number | Name | Function |
|---|---|---|
| 4657101082 | TRANSMISSION HOUSING | Main structural casing for the gear assembly |
| 4657201166 | HOUS.FRONT SECT | Front section housing for input shaft support |
| 4657201170 | HOUSING REAR PART | Rear section housing for output flange |
| 4657298102 | HOUSING REAR SECTION | Extended rear housing for PTO or brake mount |
| 0631306816 | CYLINDRICAL PIN | Alignment pin for housing assembly |
| 0636100801 | CAP SCREW | Fastener for main housing joints |
| 4656301148 | FIXING PLATE | Locks bearing or gear in position |
| 4657301032 | SCREEN SHEET | Fine mesh filter for oil circuit |
| 4657301033 | SCREEN SHEET | Coarse mesh filter for sump protection |
| 0636100803 | CAP SCREW | Fastener for rear housing section |
