Overview
The ZF 4657.183.420 LOOSE PARTS assembly is a critical internal component set designed specifically for the WG 210 series transmission. This genuine OEM part serves as a precision-matched collection of fasteners, seals, and positioning elements that secure the valve body and hydraulic control modules within the transmission housing. The SKU 4657.183.420 ensures correct alignment and clamping force, preventing fluid bypass and maintaining consistent hydraulic pressure across all gear stages. Without this specific loose parts kit, the transmission’s shift timing and torque converter lockup can become erratic, leading to premature wear on adjacent assemblies.
Symptoms of Failure
When the ZF 4657.183.420 LOOSE PARTS degrades or is improperly installed, operators frequently report intermittent gear slipping under load—a classic sign of hydraulic pressure loss. Another common failure symptom is external oil seepage around the valve body cover, often mistaken for a gasket issue but actually caused by loose or fatigued components from this kit. Technicians also encounter delayed engagement when shifting from Neutral to Drive, which worsens as the transmission warms up. Finally, erratic shift quality with harsh upshifts or soft downshifts can indicate that the loose parts are no longer maintaining proper stack height tolerances within the WG210 assembly.
Technical Specifications
| Parameter | Specification |
|---|---|
| Part Number | 4657.183.420 |
| OEM Reference | ZF 4657.183.420 |
| Material Composition | Steel alloy with zinc plating (fasteners), NBR (seals) |
| Weight (approx.) | 0.45 kg (1.0 lb) |
| Package Dimensions | 150 x 100 x 40 mm |
| Thread Pitch (primary bolts) | M8 x 1.25 |
| Operating Temperature Range | -40°C to +120°C |
Compatibility
This genuine ZF 4657.183.420 LOOSE PARTS kit is engineered for the WG 210 series transmission family, but it also shares mounting patterns with the WG180 and WG200 models produced after 2015. The kit is fully compatible with WG210 variants used in medium-duty trucks, buses, and construction equipment. For older WG180 units, verify the valve body bolt pattern before installation. The components in this kit are not interchangeable with the WG150 or WG250 series due to different housing geometries.
Related Components
| Part Number | Name | Function |
|---|---|---|
| 4657201161 | HOUS.FRONT SECT | Front housing section that aligns with the loose parts kit |
| 0636115293 | 螺栓 | High-strength bolt for securing valve body |
| 0634313603 | O-RING | Seals hydraulic passages between housing sections |
| 0631306816 | CYLINDRICAL PIN | Precision dowel for component alignment |
| 0636100801 | CAP SCREW | Fastener for cover plate retention |
| 4656301148 | FIXING PLATE | Locks loose parts in position |
| 4657301032 | SCREEN SHEET | Fine mesh filter for oil circuit |
| 4657301033 | SCREEN SHEET | Coarse mesh pre-filter |
| 0636100803 | CAP SCREW | Alternate length cap screw for deep bores |
| 4681301040 | OIL FEED.HOUSG. | Distributes oil to clutch packs |
