ZF 4646.137.019 EMERGENCY STEERING PUMP for WG251 | OEM Genuine Part

Overview

The ZF 4646.137.019 EMERGENCY STEERING PUMP is a critical hydraulic component engineered for the WG 251 Series transmission. This OEM genuine part provides auxiliary steering pressure when the primary pump loses flow, ensuring continued vehicle maneuverability during a power loss event. Located within the transmission’s hydraulic control circuit, it integrates directly with the TRANSMISSION HOUSING to maintain steering system integrity. The SKU 4646.137.019 is precision-machined to ZF’s original specifications, guaranteeing a direct fit and reliable emergency operation in heavy-duty industrial applications.

Symptoms of Failure

• Delayed or unresponsive emergency steering: When the primary pump fails, a worn 4646.137.019 pump may not generate sufficient hydraulic pressure, causing steering wheel resistance or complete loss of auxiliary control.
• Hydraulic fluid leaks around the pump housing: Degraded seals or internal wear can produce visible oil seepage near the pump mounting point, often contaminating the HOUSING and surrounding components.
• Unusual whining or grinding noises during emergency operation: Internal bearing or gear damage creates audible distress signals, particularly when the pump is engaged under load.
• Intermittent steering assist failure: The pump may sporadically fail to engage, leading to unpredictable steering behavior that compromises operator safety.

Technical Specifications

Compatibility

This emergency steering pump is primarily designed for the WG 251 Series transmission. Based on its hydraulic architecture and mounting interface, it is also compatible with the following ZF models: WG180, WG200, and WG250. Always verify the pump’s flange pattern and port orientation against your specific transmission housing. For proper installation, ensure the COVER is correctly aligned and secured using the specified CAP SCREW torque values.

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