Overview
The ZF 4699.825.145 GP25 is a critical OEM genuine gear pump assembly designed for high-pressure hydraulic actuation within ZF powershift transmissions. This component, identified by SKU 4699.825.145, is mounted directly to the transmission housing and serves as the primary oil supply source for clutch engagement, lubrication, and cooling circuits. As a positive displacement pump, it ensures consistent fluid flow to maintain gear train integrity under heavy construction loads. The GP25 designation indicates a specific displacement rating optimized for mid-range ZF transmissions, making it a direct replacement for worn units in earthmoving and material handling equipment.
Symptoms of Failure
When the ZF 4699.825.145 GP25 begins to degrade, operators often notice delayed clutch engagement or sluggish directional shifts, particularly under load. A second common failure indicator is erratic transmission pressure, which may trigger warning lights or cause the machine to lose power during grading or lifting operations. Third, audible whining or cavitation noise from the transmission sump typically signals internal pump wear or aeration. Finally, chronic low oil level warnings despite no external leaks can point to internal bypassing within the GP25 pump assembly, reducing volumetric efficiency.
Technical Specifications
| Parameter | Specification |
|---|---|
| OEM Part Number | 4699.825.145 |
| Type | GP25 Gear Pump |
| Displacement | 25 cc/rev (estimated) |
| Maximum Operating Pressure | 25 bar (363 psi) |
| Housing Material | High-Grade Aluminum Alloy |
| Weight | 4.2 kg (9.3 lbs) |
| Mounting Flange | SAE A 2-Bolt (estimated) |
| Rotation | Clockwise (viewed from drive end) |
Compatibility
This GP25 pump is engineered for integration with ZF’s WG series powershift transmissions commonly found in construction machinery. Primary compatible models include the WG180, WG200, and WG210 series, as well as select variants of the WG150 and WG160. It is also used in certain ERGO and Ecomat off-highway transmissions. Always verify the pump displacement and mounting pattern against your specific transmission serial number before installation.
Related Components
| Part Number | Name | Function |
|---|---|---|
| 4699025040 | GP25 | Gear pump assembly (alternate variant) |
| 4699101114 | HOUSING | Transmission main housing section |
| 4699102157 | INPUT | Input shaft and gear assembly |
| 4699103114 | OUTPUT | Output shaft and flange assembly |
| 4699109068 | BRAKE PARTS | Parking brake components |
| 4699301202 | HOUSING | Clutch housing section |
| 4699309205 | HOUSING COVER | Rear housing cover plate |
| 0636101477 | CAP SCREW | M10 x 30 hex flange bolt |
| 0631302221 | CYLINDRICAL PIN | Alignment dowel pin |
| 0501319149 | SCREW PLUG | Oil gallery sealing plug |
