Overview
This complete ZF 4644.036.023 6 WG 201 Powershift Transmission Assembly is a fully integrated drop-in unit designed for heavy-duty off-highway machinery. As the core drivetrain component in the WG 201 series, this assembly manages torque distribution across six forward gears and one reverse gear, enabling seamless power shifts under load. The SKU 4644.036.023 represents a factory-matched unit that includes the torque converter, clutch packs, and hydraulic control valve body pre-assembled. It sits directly between the engine flywheel and the final drive, converting high-speed engine rotation into controlled, low-speed wheel torque for graders, loaders, and industrial tractors.
Symptoms of Failure
When the ZF 4644.036.023 assembly begins to degrade, operators will notice distinct operational issues. Watch for these specific failure indicators:
- Delayed engagement or gear hunting – The transmission hesitates before moving into gear or repeatedly shifts between gears under light throttle, indicating worn clutch pack friction discs or degraded hydraulic pressure.
- External oil seepage at the bell housing – Hydraulic fluid leaking from the torque converter seal or pump gasket creates puddles under the machine, often accompanied by a burnt smell from overheated fluid.
- Intermittent power loss during uphill operation – The unit slips out of gear when climbing grades, suggesting worn planetary gear sets or a failing one-way clutch in the torque converter.
- Harsh or erratic shift quality – Abrupt clunking sounds during gear changes point to sticking shift valves or a failing pressure regulator spool inside the control valve body.
Technical Specifications
| Parameter | Value |
|---|---|
| Assembly Weight | 185 kg (408 lbs) |
| Overall Length | 720 mm |
| Overall Width | 480 mm |
| Overall Height | 510 mm |
| Housing Material | Cast iron (EN-GJL-250) |
| Clutch Disc Material | Sintered bronze on steel core |
| OEM Reference | ZF 4644.036.023 |
| Fluid Capacity | 12.5 liters (ZF TE-ML 03 spec) |
| Max Input Torque | 650 Nm |
Compatibility
This complete unit is engineered specifically for the WG 201 transmission family. It is directly compatible with the following ZF models and their derivatives:
- ZF WG 201 – All variants (6 WG 201, 6 WG 201 E, 6 WG 201 T)
- ZF WG 180 – Select models using the same bell housing pattern (verify input shaft spline count)
- ZF WG 200 – Earlier generation units with identical clutch pack stack height
- ZF 4 WG 200 – 4-speed versions that share the same hydraulic pump mounting flange
Always cross-reference your existing transmission serial number against the SKU 4644.036.023 to confirm fitment. This assembly is not backward-compatible with the WG 150 or WG 120 series without adapter plates.
