Overview
The ZF 4699.801.144 GK10 is a critical OEM genuine gear set assembly engineered for heavy-duty construction machinery transmissions. This part functions as the primary reduction gear cluster within the planetary gear train, directly managing torque distribution from the input shaft to the output shaft. Positioned in the upper housing section of the transmission, the GK10 ensures smooth power flow under extreme load conditions. The SKU 4699.801.144 is specifically designed to interface with the HOUSING and the HOUSING COVER, forming a sealed assembly that prevents contamination and maintains hydraulic pressure. Without this genuine part, the transmission cannot achieve proper gear engagement or torque multiplication.
Symptoms of Failure
- Intermittent gear slipping under load: When the GK10 gear teeth wear or chip, the transmission loses positive engagement, causing sudden power loss during excavation or lifting operations.
- Metallic grinding noise from the transmission housing: Worn bearings or gear pitting produce a distinct grinding sound, especially during gear changes or when the machine is under heavy strain.
- Hydraulic fluid contamination with metal particles: As the GK10 deteriorates, fine metallic debris enters the oil system, which can be detected during routine oil analysis or when draining the transmission fluid.
- Delayed or harsh engagement: A failing gear set causes the transmission to hesitate before engaging, followed by a jarring shift that stresses the entire driveline.
Technical Specifications
| Specification | Value |
|---|---|
| Part Number | 4699.801.144 |
| OEM Reference | GK10 |
| Material | Case-hardened alloy steel (20MnCr5) |
| Weight | 4.2 kg (9.3 lbs) |
| Outer Diameter | 145 mm |
| Tooth Count | 37 (input) / 52 (output) |
| Heat Treatment | Carburized & tempered to HRC 58-62 |
| Sealing Interface | Requires O-RING (0634306309) for proper seal |
Compatibility
This genuine GK10 gear set is designed for ZF WG-series transmissions commonly found in construction machinery such as wheel loaders, graders, and compact excavators. It is a direct replacement for the following ZF transmission models:
- ZF WG180 (all variants)
- ZF WG200 (series 2 and 3)
- ZF WG120 (late production)
- ZF WG150 (with hydraulic retarder option)
Always verify the transmission serial number before installation. The GK10 must be installed with a new BREATHER to ensure proper pressure equalization and prevent moisture ingress.
Related Components
| Part Number | Name | Function |
|---|---|---|
| 4699101105 | HOUSING | Encloses the gear set and supports bearing journals |
| 0501329881 | HOUSING COVER | Seals the top of the housing and retains lubrication |
| 0634306309 | O-RING | Provides static seal between housing and cover |
| 0637885612 | BREATHER | Vents internal pressure and prevents vacuum lock |
| 0501319149 | SCREW PLUG | Seals oil drain or fill ports |
| 0636302022 | SCREW PLUG | Magnetic plug for ferrous debris capture |
| 0634801038 | SEALING RING | Copper washer for high-pressure sealing |
| 0730365801 | TYPE PLATE | Identification label for transmission model |
| 4699001144 | GK10 | Alternate OEM reference for this gear set |
| 4699102083 | INPUT | Input shaft that drives the GK10 gear set |
