Overview
The ZF 4657.173.042 CLUTCH is a critical torque-transfer component engineered specifically for the WG 190 and WG 210 series transmissions. Positioned within the planetary gearset assembly, this OEM genuine part engages and disengages power flow between the input shaft and the intermediate shaft, enabling smooth gear shifts under heavy load. The SKU 4657.173.042 is manufactured to ZF’s exacting tolerances, ensuring precise hydraulic actuation and minimal drag during neutral operation. When installed alongside a robust TRANSMISSION HOUSING, this clutch maintains structural integrity even under sustained high-torque conditions. It is a direct replacement for worn units in both the WG 191 and WG 211 series categories.
Symptoms of Failure
- Delayed or harsh engagement: When the 4657.173.042 clutch wears, hydraulic pressure bleeds past the seals, causing a noticeable lag when shifting from neutral to drive or reverse. Operators often report a “clunk” as the clutch finally grabs.
- Torque converter shudder under load: A failing clutch disc or warped steel plate produces a low-frequency vibration during acceleration, particularly in 2nd and 3rd gears. This symptom is often misdiagnosed as a torque converter issue.
- Burnt transmission fluid odor: Slipping generates excessive heat, oxidizing the ATF. A sharp, burnt smell from the dipstick or breather indicates the clutch friction material is disintegrating.
- Intermittent loss of forward drive: As the clutch pack loses clamping force, the transmission may momentarily “freewheel” before re-engaging, especially on inclines or during trailer towing.
Technical Specifications
| Parameter | Value |
|---|---|
| Part Number | 4657.173.042 |
| Outer Diameter | 198 mm (7.80 in) |
| Inner Diameter | 142 mm (5.59 in) |
| Friction Plate Thickness | 2.8 mm (0.11 in) |
| Steel Plate Thickness | 2.0 mm (0.079 in) |
| Number of Friction Discs | 5 |
| Material | Sintered bronze on steel core |
| Weight | 1.85 kg (4.08 lbs) |
| OEM Reference | ZF 4657.173.042 |
Compatibility
This clutch is designed for ZF WG series powershift transmissions, specifically the WG 180, WG 190, WG 200, and WG 210 models. It is a direct fit for the WG 191 and WG 211 series sub-variants. The assembly requires precise alignment with the HOUS.FRONT SECT and the HOUSING REAR PART to ensure correct oil gallery alignment. Always verify the spline count and snap ring groove depth against your existing unit before installation. For proper axial retention, a CYLINDRICAL PIN is used to index the clutch piston return spring assembly.
Related Components
| Part Number | Name | Function |
|---|---|---|
| 4657101087 | TRANSMISSION HOUSING | Encloses the gearset and clutch assembly |
| 4657301172 | HOUS.FRONT SECT | Front section housing for clutch piston |
| 4657301173 | HOUSING REAR PART | Rear section supporting output shaft |
| 0631306816 | CYLINDRICAL PIN | Alignment pin for clutch return spring |
| 0636102489 | CAP SCREW | M10 bolt for housing flange |
| 4656301148 | FIXING PLATE | Locks clutch pack in position |
| 0636102463 | CAP SCREW | M8 bolt for valve body attachment |
| 4657201133 | SCREEN SHEET | Filter screen for clutch feed circuit |
| 0636115287 | CAP SCREW | M12 bolt for bell housing |
| 4657301065 | PLATE | Backing plate for clutch piston |
