Overview
The ZF 4108.012.078 P 3200 is an OEM genuine internal component engineered for the high-torque planetary gear sets found in heavy-duty construction machinery transmissions. This precision-machined part functions as a critical load-bearing element within the hydraulic control circuit, regulating oil flow to the clutch packs. Designated under SKU 4108.012.078, it interfaces directly with the main valve body and the 4108101112: HOUSING to maintain consistent hydraulic pressure during gear shifts. Its placement within the transmission ensures that power is smoothly transferred from the torque converter to the output shaft, making it indispensable for wheel loaders, graders, and excavators operating under extreme loads.
Symptoms of Failure
- Delayed or harsh gear engagement: When the 4108.012.078 wears, hydraulic pressure drops, causing a noticeable lag when shifting from neutral to drive or reverse. This symptom often worsens as transmission oil temperature rises.
- Intermittent transmission slipping under load: A worn part fails to hold pressure in the clutch circuit, leading to momentary power loss when the machine climbs grades or pushes heavy material.
- External oil seepage around the valve body: Cracks or deformation in this component allow ATF to bypass the 0636302056: SCREW PLUG and 4108201177: HOUSING interface, leaving visible drips on the transmission pan.
- Erratic shift patterns: The control module receives inconsistent feedback, causing the transmission to hunt between gears or refuse to upshift at proper RPM thresholds.
Technical Specifications
| Parameter | Value |
|---|---|
| Part Number / SKU | 4108.012.078 |
| OEM Reference | ZF P 3200 Series |
| Material | Hardened alloy steel (case-carburized) |
| Weight | 1.45 kg (3.2 lbs) |
| Outer Diameter | 82 mm |
| Overall Length | 47 mm |
| Sealing Surface Finish | Ra 0.4 µm |
| Operating Pressure Range | 12–25 bar |
| Temperature Range | -20°C to +120°C |
Compatibility
This genuine ZF part is designed for the P 3200 modular transmission family, which includes the widely used WG180, WG200, and WG210 models. It is also compatible with the 4WG-200 and 5WG-210 variants commonly installed in Volvo, Liebherr, and Caterpillar wheel loaders. The 4108.012.078 replaces earlier revision 4108.012.077 and is backward-compatible with all P 3200 housings. For proper sealing, always pair this component with a new 4108306173: GASKET and 0750110040: SHAFT SEAL. The adjacent 4108301304: BEARING COVER must be inspected for wear during replacement.
Related Components
| Part Number | Name | Function |
|---|---|---|
| 4108101112 | HOUSING | Encloses the valve body and directs oil flow |
| 4108201177 | HOUSING | Secondary housing for clutch piston assembly |
| 0636302056 | SCREW PLUG | Seals hydraulic test ports |
| 4108301304 | BEARING COVER | Protects output shaft bearing from debris |
| 4108306173 | GASKET | Prevents fluid leaks between mating surfaces |
| 0750110040 | SHAFT SEAL | Rotary seal for input shaft |
| 4108102042 | INPUT | Transfers torque from engine to transmission |
| 4108302099 | PLANET CARRIER | Holds planetary gears for speed reduction |
| 4108302007 | BEARINGSHEET | Shim set for adjusting gear lash |
| 0635332196 | BALL BEARING | Supports rotating shaft with minimal friction |
