Overview
The ZF 4661.375.025 INNER DISK CARRIER is a critical rotating component within the WG 94 series transmission assembly. This OEM genuine part functions as the central hub that houses and aligns the clutch disk packs, transferring torque from the input shaft to the planetary gear sets. Positioned directly inside the main TRANSMISSION HOUSING, the carrier interfaces with the HOUSING II to create a sealed chamber for hydraulic actuation. The SKU 4661.375.025 is precision-machined to maintain exacting clearances, ensuring smooth engagement and disengagement of the clutch packs under high-load industrial conditions.
Symptoms of Failure
- Erratic gear engagement or delayed shifting: When the inner disk carrier splines wear, the clutch disks cannot seat properly, causing hesitation or harsh shifts during acceleration.
- Low transmission oil pressure warnings: A warped or cracked carrier allows hydraulic fluid to bypass the piston seals, leading to pressure drops and eventual clutch slip.
- Metallic debris in the oil pan: Fatigue fractures in the carrier hub produce fine steel particles that contaminate the fluid, often accompanied by a grinding noise from the transmission.
- Oil leaks near the bell housing: A damaged carrier can misalign the CYLINDRICAL PIN that locates the assembly, causing seal failure and external fluid loss.
Technical Specifications
| Specification | Value |
|---|---|
| Part Number | 4661.375.025 |
| Material | High-strength alloy steel (case-hardened) |
| Outer Diameter | 195 mm (estimated) |
| Inner Spline Diameter | 85 mm (estimated) |
| Overall Height | 62 mm (estimated) |
| Weight | 2.8 kg (6.2 lbs) |
| OEM Reference | ZF 4661.375.025 |
| Torque Capacity | Up to 2,500 Nm (estimated) |
Compatibility
This inner disk carrier is engineered for the ZF WG 94 series, which includes the WG180, WG200, and WG240 transmission models commonly found in heavy-duty trucks, construction loaders, and agricultural tractors. It is also compatible with select WG 92 series variants that share the same clutch pack architecture. Always verify the TYPE PLATE on your transmission housing to confirm model identification before installation.
Related Components
| Part Number | Name | Function |
|---|---|---|
| 4661101037 | TRANSMISSION HOUSING | Main structural casing that encloses the gear train |
| 4661301099 | HOUSING II | Intermediate housing supporting the clutch drum assembly |
| 0631306174 | CYLINDRICAL PIN | Alignment dowel for precise carrier positioning |
| 0769123894 | TYPE PLATE | Identification tag with transmission serial and model |
| 0750100022 | SCREW PLUG | Seals hydraulic test ports on the housing |
| 4660201008 | SCREW PLUG | Oil drain plug for the clutch chamber |
| 0636100117 | SCREW PLUG | Magnetic plug for debris collection |
| 0501211384 | VALVE | Pressure relief valve for clutch modulation |
| 0732042156 | COMPRESSION SPRING | Returns the piston after clutch disengagement |
| 0768409154 | SCREW PLUG | Fill plug for the transmission oil circuit |
