Overview
The ZF 4657.035.004 5 WG 191 Powershift Transmission Assembly is a complete, factory-matched unit engineered for heavy-duty off-highway machinery. This assembly integrates the main gear cluster, clutch packs, and hydraulic control elements within a single robust package. As a direct replacement for the WG 191 series, it restores full power flow and shift quality in wheel loaders, dozers, and material handlers. The SKU 4657.035.004 identifies this as a complete unit, eliminating the need for piecemeal rebuilding. It sits centrally in the drivetrain, transferring torque from the engine to the final drives. For structural integrity, this assembly mates directly with the 4657101049: TRANSMISSION HOUSING, which encloses the rotating components and maintains oil circulation.
Symptoms of Failure
- Delayed or harsh engagement: When the assembly wears, internal clutch clearance increases, causing a noticeable lag or jarring shift when moving from neutral to forward or reverse.
- Intermittent gear slipping under load: Worn friction discs or degraded seals allow hydraulic pressure to bleed off, resulting in power loss during digging or climbing operations.
- External oil leaks at housing joints: Fatigue in the main casing or gasket failure often leads to fluid seepage around the bell housing or rear cover, visible as drips after shutdown.
- Unusual whining or grinding noises: Bearing wear or gear tooth damage inside the assembly produces a metallic sound that increases with engine RPM, indicating imminent internal failure.
Technical Specifications
| Parameter | Value |
|---|---|
| Part Number | 4657.035.004 |
| Assembly Type | Complete Powershift Transmission Unit |
| 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 WG 191 Series |
| Input Spline Count | 14-tooth, SAE 3 |
| Max Input Torque | 1,200 Nm |
Compatibility
This complete unit is specifically designed for the ZF WG 191 transmission family. It is also compatible with earlier WG 180 and later WG 200 series housings when used with the correct adapter components. The assembly fits models used in Case, New Holland, Liebherr, and Volvo wheel loaders from the 1990s through 2010s. For proper installation, ensure the 4657301130: HOUS.FRONT SECT and 4657301131: HOUSING REAR PART are free of cracks. Alignment is secured using a 0631306816: CYLINDRICAL PIN to index the sections precisely.
Related Components
| Part Number | Name | Function |
|---|---|---|
| 4657101049 | TRANSMISSION HOUSING | Main structural casing for gear and clutch support |
| 4657301130 | HOUS.FRONT SECT | Front section enclosing input shaft and pump drive |
| 4657301131 | HOUSING REAR PART | Rear section supporting output shaft and PTO |
| 0631306816 | CYLINDRICAL PIN | Alignment dowel for housing sections |
| 0636102489 | CAP SCREW | Fastener for housing bolt circle |
| 4656301148 | FIXING PLATE | Locks clutch piston in position |
| 0636102463 | CAP SCREW | Mounting bolt for valve body |
| 4657201133 | SCREEN SHEET | Oil filter mesh for hydraulic circuit |
| 0636115287 | CAP SCREW | High-tensile bolt for clutch pack |
| 4657301065 | PLATE | Thrust washer for gear end-play |
