Overview
The ZF 4651.004.048 4 WG 100(500) Powershift Transmission Assembly is a complete, factory-matched unit designed for heavy-duty off-highway applications. This assembly integrates the torque converter, planetary gear sets, and clutch packs into a single, pre-assembled module. As the core power transfer component in the WG 100 series, it directly replaces worn or failed assemblies to restore full driveline performance. The SKU 4651.004.048 is a direct-fit unit that eliminates the need for piecemeal rebuilding, ensuring precise alignment of internal components. This assembly sits between the engine flywheel housing and the output driveline, managing all forward and reverse gear ratios under high torque loads.
Symptoms of Failure
- Erratic shifting or gear slippage under load: When the internal clutch packs or sprag clutches wear, the transmission may hesitate, flare, or fail to hold a gear during acceleration or when climbing grades.
- External oil leaks from the main housing or bell housing interface: Cracks or seal degradation in the assembly can cause fluid to weep from the joint between the TRANSMISSION HOUSING and the torque converter section, leading to low fluid levels and overheating.
- Delayed engagement or no movement in forward/reverse: A failing assembly often exhibits a prolonged pause (2-5 seconds) before engaging a gear, or complete loss of drive in one direction due to worn piston seals or valve body issues.
- Unusual noise (grinding or whining) from the transmission center: Worn bearings or damaged planetary gears produce metallic sounds that intensify with speed, often accompanied by vibration in the shift lever or chassis.
Technical Specifications
| Parameter | Value |
|---|---|
| Part Number / SKU | 4651.004.048 |
| Assembly Type | Complete Powershift Transmission (4 WG 100(500)) |
| Dry Weight (approx.) | 185 kg (408 lbs) |
| Overall Length | 620 mm |
| Overall Width | 480 mm |
| Overall Height | 510 mm |
| Housing Material | Cast Iron (GGG-40) |
| OEM Reference | ZF 4 WG 100(500) Series |
| Torque Capacity | 500 Nm (max input) |
| Number of Speeds | 4 Forward / 4 Reverse |
Compatibility
This complete unit is engineered specifically for the ZF WG 100 series powershift transmissions, including the WG 100(500) variant. It is also compatible with the WG 180 and WG 200 series when used in identical torque-rating applications, though always verify bell housing patterns. The assembly integrates directly with the HOUSING (part 4651301029) and the HOUSING (part 4651301024) to form the complete transmission case. For sealing, use the O-RING (part 0634303928) at the main joint. Common applications include ZF 4WG-100, 4WG-180, and 4WG-200 models found in telehandlers, wheel loaders, and agricultural tractors.
Related Components
| Part Number | Name | Function |
|---|---|---|
| 4651101007 | TRANSMISSION HOUSING | Main structural case for gear train |
| 4651301029 | HOUSING | Rear cover or intermediate housing |
| 0634303928 | O-RING | Seal between housing sections |
| 4651301024 | HOUSING | Front or adapter housing |
| 4651203002 | SCREEN SHEET | Oil filter screen for hydraulic circuit |
| 4651303005 | SCREEN SHEET | Secondary oil strainer |
| 0636101032 | CAP SCREW | Fastener for housing assembly |
| 0630361028 | SEALING CAP | Closes unused ports |
| 4475280060 | SCREW PLUG | Threaded plug for drain/fill holes |
| 0634303312 | O-RING | Seal for screw plug or cap |
