ZF 4699.801.203 GK10 | OEM Genuine Part

Overview

The ZF 4699.801.203 GK10 is a genuine OEM gearset assembly designed for the upper power flow path in heavy-duty ZF transmissions. This SKU, 4699.801.203, functions as the primary reduction stage between the torque converter and the planetary gear sets, directly influencing torque multiplication and shift timing. It sits within the main transmission housing and interfaces with the input shaft to manage load distribution under high-stress construction machinery operations. As a critical rotating assembly, it ensures that power transfer remains smooth and efficient during digging, grading, and hauling cycles.

Symptoms of Failure

When the 4699.801.203 wears out, operators typically notice these specific failure indicators:

• Whining or grinding noise during acceleration: A high-pitched metallic sound from the transmission belly indicates gear tooth surface fatigue or pitting on the GK10 assembly.
• Delayed engagement or gear slippage under load: Worn gear profiles cause the transmission to hesitate before engaging forward or reverse, particularly when climbing grades.
• Metallic debris in the transmission oil pan: Flakes or silver particles in the fluid signal that the 4699.801.203 is shedding material, often accompanied by a burnt odor.
• Intermittent loss of power to the wheels: The gearset may skip teeth under heavy torque, causing sudden drops in driveline speed without engine RPM change.

Technical Specifications

Compatibility

This GK10 gearset is engineered for ZF’s WG-series powershift transmissions commonly used in wheel loaders, excavators, and telehandlers. It is a direct fit for the WG180 and WG200 models, as well as the WG210 series. It also appears in select 4WG-200 and 6WG-200 configurations. Always verify the serial number stamp on your existing gearset before ordering.

Related Components

During a GK10 replacement, it is standard practice to inspect and replace adjacent wear items. The 4699001203: GK10 is the primary assembly, but you should also evaluate the 4699101125: HOUSING for cracks, the 4699102156: INPUT shaft for spline wear, and the 4699103016: OUTPUT flange for runout. Below is a complete list of supporting parts for this assembly: