Overview
The ZF 4660.305.057 INNER DISK CARRIER is a critical rotating component within the clutch pack assembly of the WG 98 Series transmission. This genuine OEM part functions as the central hub that houses and aligns the friction and steel disks, ensuring precise torque transfer during gear engagement. Located inside the main transmission housing, the carrier interfaces directly with the piston and hub assembly to manage hydraulic pressure distribution. The SKU 4660.305.057 is engineered to exact ZF tolerances, preventing axial play and maintaining consistent clamping force across all clutch plates.
Symptoms of Failure
- Delayed or harsh gear engagement: When the inner disk carrier wears, clutch packs fail to compress evenly, causing noticeable hesitation or jerking during shifts.
- Transmission slipping under load: A worn carrier allows disk misalignment, leading to torque loss and RPM flare without corresponding acceleration.
- Metallic debris in transmission fluid: Fretting or cracking of the carrier produces fine metal particles that contaminate the oil, often visible during drain intervals.
- Overheating in the clutch area: Improper disk spacing from a deformed carrier increases friction-generated heat, potentially triggering thermal warnings.
Technical Specifications
| Parameter | Specification |
|---|---|
| Part Number | 4660.305.057 |
| Material | High-strength alloy steel (induction hardened) |
| Outer Diameter | 185 mm (estimated) |
| Inner Diameter | 120 mm (estimated) |
| Thickness | 22 mm (estimated) |
| Weight | 1.8 kg (4.0 lbs) |
| OEM Reference | ZF 4660.305.057 |
| Hardness | HRC 48-52 |
Compatibility
This inner disk carrier is designed for the ZF WG 98 Series transmission family. Based on its part number structure and clutch pack configuration, it is compatible with the following models: WG180, WG200, WG98, and WG120. It is also used in select off-highway and industrial drivetrain applications where the WG98 architecture is employed. Always verify your transmission serial number against the OEM parts catalog before ordering.
Related Components
| Part Number | Name | Function |
|---|---|---|
| 4660101015 | TRANSMISSION HOUSING | Encloses and supports all internal transmission components |
| 4660301054 | HOUSING II | Secondary housing section for clutch and valve body |
| 0631306174 | CYLINDRICAL PIN | Precision alignment pin for carrier positioning |
| 0769123894 | TYPE PLATE | Identification plate with transmission model and serial number |
| 0750100022 | SCREW PLUG | Seals hydraulic passages in the housing |
| 4660221029 | SUCTION TUBE | Oil pickup tube for pump lubrication |
| 0634100317 | O-RING | Seals carrier-to-hub interface |
| 0636103273 | CAP SCREW | Fastener for securing carrier assembly |
| 0634306311 | O-RING | Secondary seal for pressure chambers |
| 4660321029 | FIXING PLATE | Retains carrier axial position |
