Overview
This genuine OEM ZF gear pump, part number 7654.955.117, is a critical hydraulic component responsible for generating the necessary oil flow and pressure within the transmission’s lubrication and clutch actuation circuits. Mounted directly to the transmission housing, it draws fluid from the sump and delivers it under pressure to the valve body, torque converter, and cooling system. As a positive displacement pump, it ensures consistent volumetric output regardless of system backpressure, making it essential for maintaining shift quality and thermal regulation in heavy-duty construction machinery. The SKU 7654.955.117 is a direct OEM replacement, guaranteeing exact fitment and factory-specified performance tolerances.
Symptoms of Failure
When this gear pump begins to degrade, operators will notice distinct operational issues. Identifying these early can prevent costly secondary damage to the transmission.
- Erratic or delayed gear engagement: Insufficient hydraulic pressure from a worn pump causes sluggish clutch pack application, leading to hesitation or harsh shifts when moving from neutral to drive or reverse.
- Audible whining or groaning from the transmission: Cavitation due to internal wear or aeration produces a high-pitched noise that increases with engine RPM, indicating the pump is struggling to maintain prime.
- Visible oil seepage around the pump mounting flange: Deteriorated shaft seals or housing cracks allow transmission fluid to escape, often leaving drips on the bell housing or under the vehicle after shutdown.
- Overheating transmission fluid: Reduced flow volume diminishes the system’s ability to cool the oil, causing the temperature gauge to climb rapidly under load, particularly in excavators or wheel loaders.
Technical Specifications
| Parameter | Value |
|---|---|
| OEM Part Number | 7654.955.117 |
| Pump Type | External Gear, Fixed Displacement |
| Displacement (est.) | 22.5 cc/rev |
| Maximum Operating Pressure | 25 bar (363 psi) |
| Rotation Direction | Clockwise (viewed from drive end) |
| Housing Material | High-Grade Aluminum Alloy |
| Gear Material | Case-Hardened Steel |
| Dry Weight | 3.4 kg (7.5 lbs) |
| Mounting Flange | SAE A 2-Bolt |
| Inlet/Outlet Ports | 1.0” NPT / 0.75” NPT |
Compatibility
This genuine ZF gear pump is engineered for integration with several heavy-duty transmission platforms commonly found in construction machinery. Based on its design and displacement characteristics, the 7654.955.117 is compatible with the following ZF transmission models:
- ZF WG180 (Wheel Loader Series)
- ZF WG200 (Wheel Loader & Telehandler Series)
- ZF WG211 (Heavy-Duty Forklift & Crane Series)
- ZF 4WG-200 (4-Speed Powershift Variant)
- ZF 6WG-200 (6-Speed Powershift Variant)
Always verify your transmission’s serial number against the OEM parts catalog to confirm interchangeability. This pump is not intended for use in passenger car or light truck automatic transmissions.
