Overview
The ZF 4699.825.217 GP25 is a critical OEM genuine gear set designed for the planetary gear train in heavy-duty construction machinery transmissions. This part, identified by SKU 4699.825.217, functions as a primary power transfer component within the transmission’s rotating clutch assembly, converting torque from the engine into usable mechanical force for the driveline. Precision-engineered from case-hardened alloy steel, the GP25 gear set ensures smooth engagement under high load conditions, directly influencing machine tractive effort and operational efficiency. When paired with the 4699025084 GP25 companion gear, it forms a matched pair that maintains gear mesh integrity and reduces backlash in the transmission.
Symptoms of Failure
When the ZF 4699.825.217 GP25 begins to wear, operators will notice distinct performance degradation. Common failure indicators include:
- Intermittent gear slipping under load: A worn GP25 gear set loses tooth profile accuracy, causing the transmission to slip when climbing grades or moving heavy loads.
- Metallic grinding noise during shifts: Damaged gear teeth produce a high-pitched whine or grinding sound, particularly during directional changes or clutch engagement.
- Oil contamination with metallic particles: Flaking or pitting on the gear surface releases ferrous debris into the transmission fluid, visible during routine oil sampling.
- Reduced machine travel speed: Excessive wear on the GP25 reduces torque multiplication, resulting in slower forward or reverse speeds despite normal engine RPM.
Technical Specifications
| Specification | Value |
|---|---|
| Part Number | 4699.825.217 |
| Designation | GP25 (Gear Set, Planetary) |
| Material | Case-hardened alloy steel (20MnCr5 equivalent) |
| Weight | 2.85 kg (6.28 lbs) |
| Outer Diameter | 142.0 mm |
| Tooth Count | 25 (sun gear) |
| Heat Treatment | Carburized & quenched, 58-62 HRC |
| OEM Reference | ZF 4699.825.217 |
Compatibility
This genuine ZF GP25 gear set is engineered for use in the following ZF transmission models commonly found in construction machinery such as wheel loaders, graders, and telehandlers:
- ZF WG180 (all series)
- ZF WG200 (all series)
- ZF 4WG-200
- ZF 4WG-210
- ZF 5WG-200
During installation, the GP25 interfaces directly with the 4699101155 HOUSING which contains the planetary carrier, and is driven by the 4699102095 INPUT shaft assembly. Torque is transmitted to the 4699103075 OUTPUT hub, making these four components a matched set for any rebuild. Always verify your transmission serial number before ordering.
Related Components
| Part Number | Name | Function |
|---|---|---|
| 4699025084 | GP25 | Matched companion gear set for planetary assembly |
| 4699101155 | HOUSING | Planetary carrier housing for gear set retention |
| 4699102095 | INPUT | Input shaft assembly driving the GP25 |
| 4699103075 | OUTPUT | Output hub receiving torque from GP25 |
| 4699109033 | BRAKE PARTS | Brake components for transmission holding |
| 4699201018 | HOUSING | Secondary housing for clutch pack support |
| 4699309077 | HOUSING COVER | Cover sealing the transmission housing |
| 0636100132 | TORX SCREW | Fastener for gear set retention |
| 0631302072 | CYLINDRICAL PIN | Alignment pin for housing assembly |
| 0634801038 | SEALING RING | O-ring preventing oil leakage at joints |
