Overview
The ZF 4661.303.007 OUTPUT FLANGE is a critical driveline component engineered specifically for the WG94 and WG98 series transmissions. This OEM genuine part serves as the mechanical interface between the transmission output shaft and the driveshaft, transferring rotational torque from the gearbox to the vehicle’s axles. Machined from high-strength forged steel, the flange ensures precise alignment and vibration-free power delivery under heavy-duty operating conditions. The SKU 4661.303.007 is a direct replacement unit that matches ZF’s original factory specifications, eliminating the need for modifications during installation. It sits at the rear of the transmission assembly, directly coupled to the output shaft and secured within the TRANSMISSION HOUSING, while the HOUSING II provides additional structural support to the surrounding bearing pack.
Symptoms of Failure
When the 4661.303.007 output flange deteriorates, operators may notice these specific failure indicators:
- Transmission fluid leakage at the rear seal: A worn flange spline or damaged sealing surface allows oil to weep past the output shaft seal, often leaving puddles under the bell housing.
- Driveline vibration during acceleration: Excessive play between the flange and output shaft causes rotational imbalance, transmitting harsh vibrations through the chassis at highway speeds.
- Clunking noise when shifting gears: Loose flange-to-shaft engagement produces audible metallic impacts, particularly during load reversals in stop-and-go operations.
- Premature bearing wear in the transmission tail housing: A warped or cracked flange misaligns the output shaft, accelerating wear on the CYLINDRICAL PIN and adjacent thrust bearings.
Technical Specifications
| Parameter | Value |
|---|---|
| Part Number | 4661.303.007 |
| Material | Forged alloy steel (DIN 1.7225 / 42CrMo4) |
| Overall Diameter | 180 mm (7.09 in) |
| Overall Length | 95 mm (3.74 in) |
| Pilot Bore Diameter | 45 mm (1.77 in) |
| Bolt Hole Pattern | 8 x M12 on 150 mm PCD |
| Weight | 3.2 kg (7.05 lbs) |
| OEM Reference | ZF 4661.303.007 |
| Surface Treatment | Zinc-nickel plated (corrosion resistant) |
Compatibility
This output flange is designed for ZF’s WG series powershift transmissions, specifically the WG94 and WG98 models. It is also compatible with the WG180 and WG200 variants that share the same output shaft spline geometry (SAE C 10-tooth, 16/32 pitch). The flange interfaces directly with the TRANSMISSION HOUSING and the HOUSING II assembly, and it is secured using the CYLINDRICAL PIN for rotational alignment. Always verify the output shaft spline count and pilot diameter against your transmission’s serial plate—the TYPE PLATE provides the definitive model designation.
Related Components
| Part Number | Name | Function |
|---|---|---|
| 4660101019 | TRANSMISSION HOUSING | Main structural casing enclosing the gear train |
| 4660301056 | HOUSING II | Rear housing section supporting output shaft bearings |
| 0631306174 | CYLINDRICAL PIN | Alignment dowel for flange-to-shaft positioning |
| 0769123894 | TYPE PLATE | Identification plate with transmission model and serial number |
| 0750100022 | SCREW PLUG | Seals oil passages in the housing |
| 4660221031 | SUCTION TUBE | Oil pickup tube for the hydraulic pump |
| 0634100317 | O-RING | Static seal between housing sections |
| 0636103273 | CAP SCREW | Fastener for securing the flange to the shaft |
| 0634306311 | O-RING | Seal for the output flange pilot bore |
| 4660321029 | FIXING PLATE | Locking plate to prevent fastener loosening |
