ZF 4661.122.001 PRESSURE OIL PUMP for WG90/WG94 | OEM Genuine Part

Overview

The ZF 4661.122.001 PRESSURE OIL PUMP is a critical hydraulic component engineered for the WG90 and WG94 series transmissions. This OEM genuine part is responsible for generating the necessary oil pressure to lubricate gears, cool clutches, and actuate shift elements within the transmission housing. Mounted directly to the main pump drive, it draws fluid from the sump and delivers it under pressure to the valve body and torque converter. The SKU 4661.122.001 ensures exact fitment and factory-specified flow rates, preventing premature wear in high-torque applications. When replacing this pump, it is common to inspect the 4661101001: TRANSMISSION HOUSING for cracks or scoring, as debris from a failing pump can damage the housing bore.

Symptoms of Failure

• Low or erratic transmission oil pressure – A worn pump cannot maintain consistent hydraulic force, leading to delayed engagement or gear slipping under load.
• Audible whining or grinding noise from the transmission – Cavitation or worn gears inside the pump create a high-pitched sound, especially during cold starts or acceleration.
• Overheating transmission fluid – Insufficient oil flow reduces cooling capacity, causing the fluid to darken and burn, often accompanied by a sulfur smell.
• Visible oil leaks near the pump mounting area – Failed seals or a cracked 4661301007: HOUSING allow fluid to escape, leaving puddles under the vehicle.

Technical Specifications

Compatibility

This pressure oil pump is specifically designed for ZF WG90 and WG94 series transmissions, which are commonly found in medium-duty trucks, buses, and construction equipment. Based on the pump’s hydraulic output and mounting flange pattern, it may also be compatible with the WG180 and WG200 series when used with the correct 4661301093: TUBE for fluid routing. Always verify the pump drive tang alignment and the condition of the 0631306174: CYLINDRICAL PIN that secures the pump to the housing. For other models like WG120 or WG150, consult the ZF parts catalog to confirm interchangeability.

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