ZF 4656.073.028 3 WG 171 Powershift Transmission Assembly | Complete Unit

Overview

This ZF 4656.073.028 3 WG 171 Powershift Transmission Assembly is a complete, ready-to-install unit designed for heavy-duty industrial and construction machinery. As a core component of the WG 171 series, this assembly integrates the main gear train, clutch packs, and hydraulic control system into a single robust package. The SKU 4656.073.028 replaces worn or failed transmissions in loaders, dozers, and graders, ensuring reliable power transfer under extreme loads. It sits directly between the torque converter and the final drive, managing gear selection and torque multiplication for smooth operation.

Symptoms of Failure

• Delayed or harsh gear engagement: When the 4656.073.028 assembly wears, operators often experience a noticeable lag or jarring shift between forward and reverse gears, indicating internal clutch pack wear.
• Transmission oil leaks around the housing: A failing unit frequently develops seepage at the mating surfaces, particularly where the TRANSMISSION HOUSING and HOUS.FRONT SECT join, leading to low fluid levels and overheating.
• Loss of power under load: A worn assembly causes the transmission to slip during heavy lifting or pushing, with engine RPM rising without proportional vehicle speed.
• Unusual whining or grinding noises: Internal bearing or gear damage within the complete unit produces metallic sounds, especially during cold starts or low-speed operation.

Technical Specifications

Compatibility

This complete unit is engineered for the ZF WG 171 series, but its design principles extend to related modular transmissions. It is directly compatible with WG 171 models used in compact wheel loaders and telehandlers. Based on the housing and clutch configuration, it also fits select variants of the WG 180 and WG 200 series when paired with the correct HOUSING REAR PART. For proper installation, ensure the SCREEN SHEET and TUBE are inspected for debris. Always verify alignment using 0631306816: CYLINDRICAL PIN and secure with 0636100801: CAP SCREW or 0636100160: CAP SCREW as needed.

Related Components

Frequently Asked Questions

Q: Can the 4656.073.028 be rebuilt, or must it be replaced as a complete unit?
A: While internal components like clutch packs and seals can be serviced, the 4656.073.028 is typically replaced as a complete assembly to ensure all wear surfaces, bearings, and hydraulic passages are restored to factory specifications. Rebuilding requires specialized tools and access to genuine ZF parts such as the 0634313514: O-RING and 0636100803: CAP SCREW.

Q: What is the typical lifespan of this WG 171 transmission assembly under normal operating conditions?
A: With proper maintenance and clean hydraulic fluid, the 4656.073.028 can last 8,000 to 12,000 hours. Regular inspection of the SCREEN SHEET and TUBE is critical to prevent contamination from shortening service life.

Q: Does this assembly include the torque converter?
A: No, the 4656.073.028 is the transmission assembly only. It mounts directly to the torque converter housing. Ensure the TRANSMISSION HOUSING and HOUS.FRONT SECT are clean and undamaged before installation.