Overview
The ZF 4699.841.012 GK26LD is an OEM genuine transmission control valve body, a critical hydraulic component responsible for directing oil flow to actuate clutch packs and shift gears within ZF powershift transmissions. Positioned internally within the main transmission housing, this part regulates pressure and timing for smooth engagement. The SKU 4699.841.012 is a direct replacement for the original factory unit, ensuring precise hydraulic circuit performance in heavy-duty construction machinery.
Symptoms of Failure
- Delayed or harsh shifting: When the valve body wears, operators often notice a lag between gear selection and engagement, or abrupt, jarring shifts during operation.
- Transmission slipping under load: Worn internal spools or bores cause pressure loss, leading to clutch slip when the machine is pushing or lifting heavy loads.
- Oil leaks around the valve body: Degraded seals or gaskets on the 4699101086 HOUSING or 4699301223 HOUSING can allow hydraulic fluid to escape, leaving visible drips under the transmission.
- Erratic or no gear engagement: Internal contamination or valve sticking prevents the transmission from engaging specific gears, often accompanied by warning codes.
Technical Specifications
| Parameter | Value |
|---|---|
| Part Number | 4699.841.012 |
| OEM Reference | GK26LD |
| Material | High-grade aluminum alloy with hardened steel spools |
| Weight | Approx. 4.2 kg (9.3 lbs) |
| Dimensions (L x W x H) | 280 mm x 180 mm x 95 mm |
| Sealing Surface Finish | Ra 0.8 µm |
| Operating Pressure Range | 12–25 bar |
Compatibility
This valve body is engineered for ZF WG180, WG200, and WG211 series powershift transmissions commonly found in wheel loaders, graders, and dump trucks. It also fits select Ergopower and Ecomat variants used in construction machinery from manufacturers like Liebherr, Volvo, and Caterpillar. Always verify the transmission serial number before installation.
During replacement, it is essential to inspect the 0636302022 SCREW PLUG and 0501319149 SCREW PLUG for thread damage, as these seal critical oil passages. The 0634801038 SEALING RING and 0501323165 SHAFT SEAL should also be renewed to prevent future leaks. For complete assembly, the 4699301222 COVER and 0634303996 O-RING provide proper enclosure, while the 0630513060 SNAP RING secures internal components. Finally, affix the 0730365801 TYPE PLATE after installation for accurate identification.
Related Components
| Part Number | Name | Function |
|---|---|---|
| 4699101086 | HOUSING | Encloses valve body and directs oil flow |
| 4699301223 | HOUSING | Secondary housing for clutch control circuits |
| 0636302022 | SCREW PLUG | Seals high-pressure oil galleries |
| 0501319149 | SCREW PLUG | Threaded plug for test ports |
| 0634801038 | SEALING RING | Prevents fluid bypass at plug interfaces |
| 0730365801 | TYPE PLATE | Identification label for transmission model |
| 0501323165 | SHAFT SEAL | Prevents oil leakage at rotating shafts |
| 4699301222 | COVER | Protects valve body from debris |
| 0634303996 | O-RING | Seals cover-to-housing joint |
| 0630513060 | SNAP RING | Retains valve spools in bore |
