Overview
This ZF 4644.004.219 4 WG 180(500) Powershift Transmission Assembly represents a complete, factory-grade replacement unit designed for heavy-duty off-highway applications. As a fully assembled drop-in solution, it integrates the torque converter, planetary gear sets, and hydraulic control system into a single, pre-tested package. The SKU 4644.004.219 is specifically engineered for the WG 180 series, serving as the primary power transfer interface between the engine and driveline in wheel loaders, dozers, and material handlers. This complete assembly eliminates the need for piecemeal component sourcing, reducing downtime during major transmission overhauls.
Symptoms of Failure
When the ZF 4644.004.219 assembly begins to degrade, operators will notice distinct operational deficits. Recognizing these signs early can prevent catastrophic drivetrain damage.
- Delayed engagement or “slip” under load: The transmission hesitates before moving forward or reverse, or the machine loses power when pushing into a pile. This is a classic sign of worn clutch packs or degraded seals within the assembly.
- Erratic shifting and gear hunting: The transmission shifts harshly, skips gears, or constantly hunts between forward ranges without operator input. This often points to internal hydraulic pressure loss or valve body wear.
- External oil leaks at bell housing or output flange: Puddles of transmission fluid forming under the machine, particularly near the engine-transmission mating point or the rear output seal, indicate compromised gaskets or seal rings inside the 4644.004.219 unit.
- Unusual noise (whining or grinding): A high-pitched whine during acceleration or a grinding sound when shifting ranges suggests bearing failure or gear tooth damage within the planetary section.
Technical Specifications
| Specification | Value |
|---|---|
| Part Number / SKU | 4644.004.219 |
| Assembly Type | Complete Powershift Unit (4 WG 180) |
| Dry Weight (approx.) | 485 kg (1,069 lbs) |
| Overall Length (approx.) | 720 mm (28.3 in) |
| Bell Housing Diameter | SAE #1 (18 in) |
| Primary Material | High-tensile cast iron housing, hardened steel gears |
| OEM Reference | ZF 4644.004.219 (Direct replacement) |
| Torque Capacity (max) | 500 Nm (369 lb-ft) |
Compatibility
This complete assembly is precision-machined for the ZF WG 180 series transmissions. While the 4644.004.219 designation is specific to the 4-speed variant with a 500 Nm torque rating, it shares physical mounting patterns and hydraulic interfaces with the broader WG family. It is directly compatible with:
- ZF WG 180 (4-speed and 6-speed variants with matching bell housing)
- ZF WG 200 series (with adapter plate verification required)
- ZF 4 WG 180(500) models used in Case, New Holland, Liebherr, and Volvo wheel loaders from the 2000-2015 production era.
Note: Always verify the torque converter pilot diameter and output yoke spline count against your specific machine model before installation. The 4644.004.219 unit is not backward-compatible with the older WG 160 series without significant modifications.
