Overview
The ZF 4699.825.133 GP25 is a critical OEM genuine gear set component engineered for heavy-duty construction machinery transmissions. This part functions as a primary power transfer element within the planetary gear assembly, converting torque from the engine into usable rotational force for the drivetrain. Specifically, the SKU 4699.825.133 sits within the intermediate shaft cluster of ZF’s WG-series transmissions, where it meshes directly with the 4699025067: GP25 to maintain precise gear ratios under extreme loads. Its hardened steel construction ensures durability in demanding environments like excavators and wheel loaders.
Symptoms of Failure
When the ZF 4699.825.133 GP25 begins to wear, operators may notice distinct performance issues. Common failure symptoms include:
- Gear slipping under load – The transmission hesitates or loses power during acceleration, especially when climbing grades or lifting heavy materials.
- Metallic grinding noises – A high-pitched whine or grinding sound from the transmission housing indicates tooth surface fatigue or pitting on the GP25 gear.
- Oil contamination with metal shavings – Worn gear teeth shed fine metallic particles into the transmission fluid, visible during routine oil changes.
- Erratic shifting patterns – The transmission may shift harshly or fail to engage certain gears due to improper gear mesh alignment.
Technical Specifications
| Specification | Value |
|---|---|
| Part Number | 4699.825.133 |
| Product Name | GP25 Gear Set |
| Material | Case-hardened alloy steel (20MnCr5 equivalent) |
| Weight | 2.85 kg (6.28 lbs) |
| Outer Diameter | 145 mm |
| Tooth Count | 25 teeth (helical cut) |
| OEM Reference | ZF 4699.825.133 |
| Heat Treatment | Carburized and quenched (58-62 HRC) |
Compatibility
This OEM genuine part is designed for use in ZF WG-series transmissions commonly found in construction machinery. Compatible models include:
- ZF WG180 – Used in mid-size wheel loaders and telehandlers.
- ZF WG200 – Applied in heavy excavators and dump trucks.
- ZF WG210 – Found in large articulated haulers.
- ZF WG250 – Installed in high-torque mining equipment.
During installation, the GP25 gear interfaces with the 4699101071: HOUSING and the 4699102106: INPUT shaft assembly. Proper alignment with the 4699103104: OUTPUT shaft is essential to prevent premature wear. Always inspect companion components like the 4699109062: BRAKE PARTS and 0634801038: SEALING RING when replacing this gear set.
Related Components
| Part Number | Name | Function |
|---|---|---|
| 4699025067 | GP25 | Matched gear set for torque distribution |
| 4699101071 | HOUSING | Encloses and supports gear assembly |
| 4699102106 | INPUT | Transfers engine power to gear train |
| 4699103104 | OUTPUT | Delivers rotational force to driveline |
| 4699109062 | BRAKE PARTS | Provides holding torque for gear engagement |
| 4699301145 | HOUSING | Secondary housing for clutch pack |
| 4699309085 | HOUSING COVER | Seals and protects internal components |
| 0636101411 | CAP SCREW | Fastens housing sections together |
| 0631302212 | CYLINDRICAL PIN | Aligns gear set during assembly |
| 0634801038 | SEALING RING | Prevents fluid leakage at shaft interfaces |
