ZF 4699.823.047 GP21 | OEM Genuine Part

Overview

The ZF 4699.823.047 GP21 is a genuine OEM gear pump assembly engineered for high-pressure hydraulic circuits within ZF construction machinery transmissions. This component is responsible for delivering consistent oil flow to the torque converter and lubrication system, ensuring reliable clutch engagement and thermal regulation. The SKU 4699.823.047 is a direct-fit replacement that maintains original factory tolerances, reducing the risk of cavitation and pressure drop in demanding earthmoving applications. Positioned on the transmission pump drive housing, it interfaces directly with the input shaft to generate hydraulic power for gear shifts.

Symptoms of Failure

• Intermittent gear slipping under load: When the GP21 loses internal clearance, hydraulic pressure fluctuates, causing clutches to disengage momentarily during heavy digging or grading operations.
• Oil leaks from the pump housing seal area: Worn O-rings or housing cracks around the 4699.823.047 lead to visible drips near the transmission bell housing, often mistaken for main seal failures.
• Whining or cavitation noise at idle: Air ingestion due to a failing pump or restricted suction line creates a high-pitched sound that worsens as hydraulic demand increases.
• Delayed forward/reverse engagement: Reduced pump output extends the time required to build clutch pressure, resulting in sluggish direction changes in wheel loaders or excavators.

Technical Specifications

Compatibility

This GP21 pump is primarily used in ZF WG180, WG200, and WG210 series powershift transmissions found in construction machinery such as loaders, dozers, and graders. It also fits select models of the ZF Ergopower and Ecolite transmission families. For accurate fitment, always verify the pump mounting flange pattern and drive tang dimensions against your existing unit. The 4699001092 GK10 gear kit is often replaced simultaneously to restore volumetric efficiency. The 4699101094 HOUSING provides the structural support for this pump, while the 4699103063 OUTPUT shaft transfers torque from the transmission to the pump drive. A 0501329881 HOUSING COVER seals the pump cavity and prevents contamination ingress.

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