ZF 4657.024.026 4 WG 190 Powershift Transmission Assembly | Complete Unit

Overview

This ZF 4657.024.026 4 WG 190 Powershift Transmission Assembly represents a complete, ready-to-install unit designed for heavy-duty industrial applications. As the core assembly for the WG 190 series, this part integrates the main gear cluster, clutch packs, and hydraulic control components into a single robust package. The SKU 4657.024.026 is engineered to deliver precise power distribution and smooth shifting under extreme loads, making it a critical replacement for machinery operating in construction, mining, and material handling environments. When installing this complete unit, ensure the TRANSMISSION HOUSING is properly aligned to prevent premature wear on the internal components.

Symptoms of Failure

• Erratic gear engagement under load: When the 4657.024.026 assembly begins to fail, operators often report delayed or harsh shifting, particularly when moving from neutral to forward or reverse. This is a common symptom of worn clutch discs or degraded hydraulic seals within the unit.
• Transmission fluid contamination with metallic debris: A failing complete unit will generate fine metal particles from gear or bearing wear, visible as glitter in the oil. This often accompanies a burnt smell from overheated friction material.
• Loss of power transfer at high torque: The assembly may slip or fail to transmit full engine power, especially during uphill travel or when carrying heavy loads. This symptom typically worsens as internal clearances increase.
• External oil seepage from housing joints: Leaks often develop at the interface between the main assembly and the HOUS.FRONT SECT, indicating gasket failure or housing distortion.

Technical Specifications

Compatibility

This complete unit is specifically engineered for the ZF WG 190 series. While the 4657.024.026 is a direct fit for the WG 190 model, it shares mounting patterns and hydraulic interfaces with the WG 180 and WG 200 series transmissions. For installations requiring a different housing configuration, the HOUSING REAR PART can be swapped to adapt the assembly for specific vehicle chassis. Always verify the CYLINDRICAL PIN alignment during installation to ensure proper dowel engagement across compatible models.

Related Components

Frequently Asked Questions

Q: Can the 4657.024.026 be rebuilt, or must it be replaced as a complete unit?
A: While individual components like clutch discs and seals can be serviced, the assembly is factory-balanced and pressure-tested. For optimal reliability, replacement as a complete unit is recommended, especially if internal wear has caused housing damage.

Q: What is the typical service interval for this ZF 4 WG 190 assembly?
A: Under normal operating conditions, the unit should be inspected every 2,000 hours. Heavy applications with frequent direction changes may require earlier evaluation of the clutch packs and hydraulic seals.

Q: Does this complete unit include the valve body and torque converter?
A: The 4657.024.026 includes the main gear assembly, clutch packs, and integrated hydraulic controls. The torque converter and external valve body are separate components and must be ordered individually for a full drivetrain rebuild.