Overview
This ZF 4656.073.051 3 WG 171 Powershift Transmission Assembly is a complete, factory-matched unit designed for heavy-duty off-highway applications. As the core hydraulic-mechanical assembly in the WG 171 series, it integrates the main drive clutch packs, planetary gear sets, and valve body into a single ready-to-install package. The SKU 4656.073.051 replaces worn or failed assemblies to restore full power flow and shift quality in loaders, dozers, and graders. It mounts directly between the engine bellhousing and the final drive, with the TRANSMISSION HOUSING providing the structural backbone for all rotating components.
Symptoms of Failure
- Delayed or harsh engagement – When the assembly loses internal seal integrity, you may experience a noticeable lag or slam when shifting from neutral to forward or reverse. This is a common sign of worn clutch piston seals inside the 4656.073.051 unit.
- Oil leaks at the housing joint – Fluid weeping from the seam between the main case and the HOUS.FRONT SECT indicates a failed gasket or cracked casting. Left unchecked, this leads to low line pressure and eventual gear slipping.
- Metallic debris in the oil pan – Fine steel or bronze particles found during routine fluid changes point to bearing or gear wear within the assembly. This often coincides with a clogged SCREEN SHEET, restricting lubrication flow.
- Intermittent loss of drive in high range – A failing spool valve or damaged TUBE can cause pressure drop to the high-range clutch pack, resulting in sporadic power delivery under load.
Technical Specifications
| Parameter | Value |
|---|---|
| Part Number | 4656.073.051 |
| Assembly Type | Complete Powershift Transmission (3 WG 171) |
| 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 4656.073.051 / 3 WG 171 |
| Seal Kit O-Ring | 0634313514 |
| Mounting Hardware | 0636100803 (CAP SCREW) / 0636100801 (CAP SCREW) / 0636100160 (CAP SCREW) |
| Rear Housing | 4656301042 (HOUSING REAR PART) |
| Alignment Pin | 0631306816 (CYLINDRICAL PIN) |
Compatibility
This 4656.073.051 assembly is engineered specifically for the ZF WG 171 series powershift transmissions. It is also compatible with the WG 180 and WG 200 series when used as a direct replacement for the main gearbox section, provided the vehicle uses the same bellhousing pattern and output flange. Common applications include ZF 3 WG 171, 4 WG 180, and 4 WG 200 models found in construction equipment from 1995 onward. Always verify the serial number range against your existing unit before installation.
Related Components
| Part Number | Name | Function |
|---|---|---|
| 4656101028 | TRANSMISSION HOUSING | Main structural case for gear and shaft support |
| 4656301066 | HOUS.FRONT SECT | Front section housing for pump drive and input shaft |
| 4656201015 | SCREEN SHEET | Fine mesh filter protecting valve body from debris |
| 4656301037 | TUBE | Pressure feed tube for clutch lubrication circuit |
| 0634313514 | O-RING | Seals hydraulic passages between housing sections |
| 0636100803 | CAP SCREW | M10 fastener for main housing bolts |
| 4656301042 | HOUSING REAR PART | Rear cover housing for output shaft bearing |
| 0631306816 | CYLINDRICAL PIN | Dowel pin for precise alignment of housing halves |
| 0636100801 | CAP SCREW | M12 fastener for front section attachment |
| 0636100160 | CAP SCREW | M8 fastener for screen sheet and tube brackets |
Frequently Asked Questions
Q: Can I install this 4656.073.051 assembly without replacing the transmission housing?
A: Yes, but we strongly recommend inspecting the TRANSMISSION HOUSING for cracks or wear at the bearing bores. A damaged housing will compromise the alignment of the new assembly and lead to premature failure.
Q: What is the typical service life of this complete unit?
A: Under normal operating conditions with proper fluid maintenance, the 3 WG 171 assembly can last 8,000 to 12,000 hours. Debris contamination from a clogged SCREEN SHEET is the most common cause of early failure.
Q: Does this part include the front section housing?
A: No, the 4656.073.051 is the main gearbox assembly only. The HOUS.FRONT SECT and its associated CAP SCREW set must be ordered separately if needed.
📞 Need this part? Contact our ZF specialists:
Email: info@partszf.com |
Phone: +86 158 2286 3467 |
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