Overview
The ZF 4474.051.294 WH-L 3075 II is an OEM genuine hydraulic control unit designed for heavy-duty powershift transmissions used in construction machinery. This component governs the precise flow of transmission fluid to modulate clutch engagement and gear selection, ensuring smooth power delivery under extreme load conditions. Positioned within the valve body assembly, the WH-L 3075 II acts as the central command interface between the operator’s input and the transmission’s internal hydraulics. The SKU 4474.051.294 distinguishes this unit as a direct replacement part, manufactured to ZF’s original tolerances for reliable performance in excavators, wheel loaders, and graders.
Symptoms of Failure
When the ZF 4474.051.294 begins to degrade, operators often notice distinct operational anomalies. Below are the most common failure indicators that signal the need for immediate replacement:
- Erratic gear engagement or delayed shifting — The transmission hesitates or clunks when moving between forward and reverse, particularly under load. This is a frequent search query for “ZF transmission shifting problems.”
- Internal hydraulic fluid leaks — Visible oil seepage around the valve body or a persistent drop in transmission fluid level without external line damage. Users often search for “ZF WH-L 3075 oil leak fix.”
- Transmission overheating — The unit runs hotter than normal due to improper fluid routing, causing the torque converter to slip. This symptom is commonly queried as “construction machinery transmission overheating causes.”
- Loss of power during acceleration — The machine struggles to maintain speed on inclines or under heavy bucket loads, indicating the control unit is not maintaining adequate clutch pressure.
Technical Specifications
| Specification | Value |
|---|---|
| OEM Part Number | 4474.051.294 |
| Product Designation | WH-L 3075 II |
| Material | High-grade aluminum alloy with hardened steel spools |
| Weight | 4.2 kg (9.3 lbs) |
| Dimensions (L x W x H) | 285 mm x 145 mm x 95 mm |
| Operating Pressure Range | 12–25 bar (174–363 psi) |
| Fluid Compatibility | ZF TE-ML 03, 05, or 07 approved oils |
| OEM Reference | ZF Friedrichshafen AG genuine |
Compatibility
This control unit is engineered for integration with specific ZF transmission families commonly deployed in construction machinery. Based on its hydraulic design and port configuration, the 4474.051.294 is compatible with the following ZF models:
- ZF WG180 — Used in mid-size wheel loaders and telehandlers.
- ZF WG200 — Found in heavy excavators and articulated dump trucks.
- ZF 4WG-200 — A variant for high-torque applications in mining equipment.
- ZF 6WG-250 — Powershift transmission for large graders and dozers.
Always verify the transmission serial number and hydraulic circuit layout before installation, as minor revisions may affect port alignment.
