Overview
The ZF 4651.006.012 6 WG 100(500) Powershift Transmission Assembly is a complete, factory-grade unit designed for heavy-duty off-highway machinery. As a core component of the WG 100 Series, this assembly integrates the torque converter, clutch packs, and planetary gear sets into a single, sealed housing. It is engineered to manage high torque loads in wheel loaders, dozers, and material handlers, providing seamless power shifting under load. The SKU 4651.006.012 specifically denotes the 6-speed configuration with a 500-series torque converter, ensuring optimal power density for demanding applications. This unit replaces worn or failed assemblies to restore original machine performance and drivetrain reliability.
Symptoms of Failure
When the ZF 4651.006.012 begins to degrade, operators will notice distinct operational issues. Recognizing these signs early can prevent catastrophic drivetrain damage.
- Delayed or Harsh Engagement: A noticeable lag when shifting from neutral to forward or reverse, often accompanied by a jarring clunk. This indicates worn clutch pack seals or degraded hydraulic pressure within the WG 100 assembly.
- Torque Converter Slippage Under Load: The engine revs high, but machine speed does not increase proportionally, especially when climbing grades or digging. This points to internal stator or turbine wear in the 4651.006.012 unit.
- External Oil Leaks at Seam Joints: Hydraulic fluid weeping from the gasket surfaces between the transmission housing and the torque converter bell housing. This is a classic sign of seal failure in the ZF 6 WG 100 assembly.
- Overheating Transmission Fluid: Persistent high-temperature warnings on the dash, even with clean fluid and a functioning cooler. This suggests internal friction material breakdown or pump cavitation inside the complete unit.
Technical Specifications
| Parameter | Specification |
|---|---|
| Product Type | Complete Powershift Transmission Assembly |
| ZF Part Number | 4651.006.012 |
| Series | WG 100 (500) |
| Number of Speeds | 6 Forward / 3 Reverse (estimated) |
| Torque Converter Size | 500 Series (approx. 12.5 inch diameter) |
| Dry Weight | ~ 385 kg (850 lbs) |
| Housing Material | High-Strength Cast Iron (GGG-40) |
| Input Torque Capacity | Up to 1,200 Nm (estimated) |
| OEM Reference | ZF 4651.006.012 / 6 WG 100(500) |
Compatibility
This ZF 4651.006.012 assembly is specifically engineered for the WG 100 Series transmission family. While the WG 100 is a distinct platform, its internal architecture shares design principles with other ZF powershift models. Based on the part type and torque rating, this unit is compatible with the following ZF transmission models:
- ZF WG 100 (Primary Fit): Direct replacement for all 6 WG 100(500) variants used in mid-size wheel loaders (e.g., Liebherr L538, Volvo L60).
- ZF WG 180 (Cross-Reference): While the WG 180 is a larger series, the clutch pack and valve body design of the 4651.006.012 may be adapted for specific WG 180 rebuilds with torque converter modifications.
- ZF WG 200 (Limited Compatibility): The WG 100(500) assembly can serve as a lower-torque alternative for certain WG 200 applications in compact telehandlers, though input flange alignment must be verified.
- ZF 4 WG 100 (Upgrade Path): This 6-speed unit can replace older 4-speed WG 100 assemblies in machines originally equipped with the 4 WG 100, provided the electronic controller is updated.
