Overview
The ZF 4657.183.138 LOOSE PARTS kit is an OEM genuine sub-assembly designed specifically for the WG 211 Series transmission. This collection of loose components serves as the foundational hardware for the valve body and hydraulic control unit, ensuring precise fluid routing and pressure containment within the gearbox. The SKU 4657.183.138 is a critical replenishment set that includes fasteners, spacers, and sealing elements required to secure the 4657120005: PRESSURE REGULATOR and 0501211384: VALVE assemblies during rebuilds. Without this hardware, the transmission cannot maintain hydraulic integrity, leading to erratic shift behavior.
Symptoms of Failure
When the ZF 4657.183.138 loose parts degrade or are missing during reassembly, operators typically encounter these specific failure modes:
- Hydraulic fluid seepage at valve body joints – Worn or missing sealing washers from this kit cause external oil leaks, often mistaken for pan gasket failures.
- Intermittent gear slippage under load – Loose fasteners allow the 0630532183: INDENTED RING to shift, disrupting clutch pack engagement pressure.
- Delayed or harsh upshifts – Degraded spacers prevent the 4656306145: PISTON from seating correctly, causing pressure spikes in the hydraulic circuit.
- Unusual whining noise from the transmission sump – Missing retaining clips allow loose hardware to circulate, damaging pump gears.
Technical Specifications
| Parameter | Value |
|---|---|
| Part Number | 4657.183.138 |
| Material Composition | Steel (zinc-plated) & NBR rubber |
| Weight (approx.) | 0.45 kg (1.0 lb) |
| OEM Reference | ZF 4657.183.138 |
| Thread Size (primary bolts) | M6 x 1.0 |
| Operating Temperature Range | -40°C to +120°C |
Compatibility
This LOOSE PARTS kit is engineered for the ZF WG 211 Series transmission family. Based on its hardware configuration, it is also compatible with the following ZF models that share the same valve body architecture: WG180, WG200, WG210, and WG220. Always verify the presence of the 4657101049: TRANSMISSION HOUSING and 4657301130: HOUS.FRONT SECT to confirm fitment, as these housings dictate the bolt pattern for the 4657.183.138 kit.
Related Components
| Part Number | Name | Function |
|---|---|---|
| 4657120005 | PRESSURE REGULATOR | Controls main line pressure to the valve body |
| 0501211384 | VALVE | Directs hydraulic flow for shift timing |
| 0630532183 | INDENTED RING | Locks piston assemblies in place |
| 4656306145 | PISTON | Applies clutch pack force hydraulically |
| 0732042767 | COMPRESSION SPRING | Returns valve spools to neutral position |
| 0631612064 | SET SCREW | Secures adjustment points on the valve body |
| 0631610026 | SET SCREW | Locks pressure regulator adjustment |
| 4657101049 | TRANSMISSION HOUSING | Main structural case for the gearbox |
| 4657301130 | HOUS.FRONT SECT | Front section of the transmission housing |
| 4657301131 | HOUSING REAR PART | Rear section of the transmission housing |
