ZF 4644.108.053 COUNTERSHAFT for WG201 | OEM Genuine Part

Overview

The ZF 4644.108.053 COUNTERSHAFT is a critical internal component engineered specifically for the WG 201 series transmission. This genuine OEM part functions as the primary torque-transfer shaft, synchronizing gear rotation and distributing engine power across the transmission’s planetary gear sets. Positioned within the main gear train, the countershaft works in direct conjunction with the 4644101203: TRANSMISSION HOUSING and the 4644301382: TRANSMISSION HOUSING to maintain precise alignment and load distribution. The SKU 4644.108.053 is laser-etched on the shaft for traceability, ensuring you receive a factory-matched replacement that meets ZF’s strict tolerances for heavy-duty industrial applications.

Symptoms of Failure

When the 4644.108.053 countershaft begins to wear, operators often notice erratic gear engagement during shifting, particularly under load. A second common indicator is low-frequency vibration or humming emanating from the transmission housing, which intensifies at highway speeds. You may also observe metal particles in the transmission fluid during routine oil changes, signaling that the shaft’s hardened surface is degrading. Finally, intermittent loss of power to the wheels—often misdiagnosed as a clutch issue—can occur when the countershaft’s splines strip or develop micro-cracks.

Technical Specifications

Compatibility

This genuine ZF countershaft is primarily designed for the WG 201 series transmissions, which are widely used in municipal buses, fire trucks, and medium-duty construction vehicles. It is also compatible with the WG 180 and WG 200 series, provided the transmission housing and bearing carriers are from the same generation. For proper installation, always pair this shaft with a new 0636302005: SCREW PLUG and inspect the 4644301189: THREADED BUSH for wear. The part is not backward-compatible with pre-2005 ZF 4HP or 5HP series without significant modification.

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