ZF 4699.803.072 GK20 II | OEM Genuine Part

Overview

The ZF 4699.803.072 GK20 II is a precision-engineered gear set assembly designed for the countershaft cluster within heavy-duty ZF powershift transmissions. This OEM genuine part, identified by SKU 4699.803.072, functions as the primary torque transfer interface between the input shaft and the output shaft in construction machinery drivelines. It sits directly within the transmission housing, meshing with the 4699101109 HOUSING to ensure smooth power delivery under extreme load conditions. The GK20 II designation indicates its specific gear ratio and tooth geometry, optimized for high-torque, low-speed applications found in wheel loaders and excavators.

Symptoms of Failure

• Intermittent gear slipping under load: When the 4699.803.072 gear teeth wear unevenly, the transmission may momentarily lose power during heavy digging or lifting operations, a condition often searched as “ZF transmission slipping under load.”
• Metallic whining or grinding noise from the transmission: Worn gear faces produce a distinct high-pitched whine that increases with engine RPM, commonly described as “ZF GK20 gear noise” in service manuals.
• Oil contamination with metallic particles: As the gear surface flakes, fine steel particles appear in the transmission fluid, detectable during routine oil analysis, leading to searches like “metal shavings in ZF transmission oil.”
• Hard shifting or delayed engagement: Excessive gear wear causes misalignment with the 4699102160 INPUT shaft, resulting in sluggish clutch pack engagement and harsh gear changes.

Technical Specifications

Compatibility

This GK20 II gear set is engineered for ZF WG180, WG200, and WG210 series powershift transmissions commonly installed in construction machinery from manufacturers such as Caterpillar, Volvo, and Liebherr. It directly interfaces with the 4699103030 OUTPUT shaft assembly and requires the 4699003074 GK20 II companion gear for complete pairing. The part is also compatible with select ZF 4WG-200 and 6WG-200 variants used in telescopic handlers and graders.

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