Overview
The ZF 4699.825.278 GP25 is a critical OEM genuine gearset assembly designed for heavy-duty construction machinery transmissions. This part, identified by SKU 4699.825.278, functions as a primary power transfer component within the planetary gear train, converting rotational torque from the input shaft to the output shaft while managing gear ratio changes. It sits directly within the transmission housing, interfacing with the clutch pack and hydraulic control system to ensure smooth shifting under extreme loads. As a genuine ZF component, it guarantees precise tolerances and metallurgical integrity for demanding earthmoving applications.
Symptoms of Failure
When the ZF 4699.825.278 GP25 wears out, operators typically notice these specific failure modes:
- Intermittent gear slipping under load – The transmission loses torque transfer when climbing grades or moving heavy material, often accompanied by a whining noise from the planetary set.
- Metallic debris in transmission fluid – Worn gear teeth shed particles that contaminate the oil, visible during routine drain intervals or as a gritty texture on the dipstick.
- Delayed engagement or harsh shifting – The GP25’s worn splines or bearing surfaces cause hesitation when shifting from neutral to drive or reverse, with a noticeable clunk.
- Oil leaks near the transmission bell housing – Degraded seals around the gearset allow hydraulic fluid to escape, leaving puddles under the equipment after operation.
Technical Specifications
| Specification | Value |
|---|---|
| Part Number | 4699.825.278 |
| Product Name | GP25 Gearset Assembly |
| Material | Case-hardened alloy steel (20MnCr5) |
| Weight | 8.4 kg (18.5 lbs) |
| Outer Diameter | 195 mm |
| Overall Length | 142 mm |
| OEM Reference | ZF 4699.825.278 |
| Torque Capacity | 2,800 Nm (2,065 ft-lbs) |
| Operating Temperature Range | -20°C to +120°C |
Compatibility
This ZF 4699.825.278 GP25 is engineered for use in the following ZF transmission models commonly found in construction machinery such as wheel loaders, graders, and excavators:
- ZF WG180 – 4-speed powershift transmission for medium wheel loaders
- ZF WG200 – Heavy-duty 4-speed transmission for large excavators
- ZF WG150 – Compact 3-speed transmission for backhoe loaders
- ZF 4WG-200 – 4-speed countershaft transmission for articulated dump trucks
For optimal performance, this gearset is installed alongside the 4699025172 GP25 companion gear, the 4699101154 HOUSING that encloses the assembly, the 4699102106 INPUT shaft that drives it, and the 4699103123 OUTPUT shaft that transfers torque to the driveline. Proper alignment of these components is essential to prevent premature wear.
Related Components
| Part Number | Name | Function |
|---|---|---|
| 4699025172 | GP25 | Companion gearset for torque distribution |
| 4699101154 | HOUSING | Encloses and supports the gearset assembly |
| 4699102106 | INPUT | Drives the GP25 from the torque converter |
| 4699103123 | OUTPUT | Transfers torque to the differential |
| 4699109111 | BRAKE PARTS | Brake components for gearset stopping |
| 4699301249 | HOUSING | Secondary housing for clutch pack |
| 4699309121 | HOUSING COVER | Seals the transmission housing |
| 0636101411 | CAP SCREW | Fastens housing components |
| 0631302072 | CYLINDRICAL PIN | Aligns gearset during assembly |
| 0636302013 | SCREW PLUG | Seals fluid passages in housing |
