Overview
The ZF 4644.183.027 LOOSE PARTS set is a critical service kit designed for the WG 201 series transmission. This genuine OEM assembly includes all necessary fasteners, seals, and positioning components required to secure internal valve body and clutch pack assemblies within the main transmission housing. The SKU 4644.183.027 specifically addresses the retention and alignment of loose components that can shift during high-torque operation, ensuring precise hydraulic flow paths are maintained. When paired with a new 4644101160: TRANSMISSION HOUSING or a refurbished 4644301323: TRANSMISSION HOUSING, this kit restores factory-spec clamping force and eliminates internal play.
Symptoms of Failure
- Intermittent gear slippage under load: Worn or missing loose parts allow valve body movement, causing pressure loss to clutch packs during acceleration.
- Metallic rattling from the bell housing: Unsecured components vibrate against the 4644301189: THREADED BUSH and housing walls, producing a distinct noise at idle.
- Hydraulic fluid contamination: Degraded loose parts shed debris into the oil circuit, clogging the 4475280043: SCREW PLUG passages and reducing shift quality.
- Hard shifting or delayed engagement: Misaligned components prevent proper seating of the control valve, leading to harsh 1-2 upshifts.
Technical Specifications
| Parameter | Specification |
|---|---|
| OEM Part Number | 4644.183.027 |
| Material Composition | Hardened steel / Nitrile rubber (seals) |
| Overall Dimensions | 120 mm x 80 mm x 35 mm (kit packaging) |
| Weight | 0.45 kg (1.0 lb) |
| Thread Pitch (primary fasteners) | M8 x 1.25 |
| Temperature Range | -40°C to +150°C |
| OEM Reference | ZF 4644.183.027 |
Compatibility
This genuine ZF 4644.183.027 LOOSE PARTS set is engineered for the WG 201 series, but its retention geometry also applies to the WG 180, WG 200, and WG 211 models. It is a direct fit for any transmission using the 4644-series housing architecture. For proper sealing, always replace the 0634306198: O-RING and verify the 0730365067: TYPE PLATE matches your unit’s revision. The kit works with both standard and heavy-duty clutch configurations.
Related Components
| Part Number | Name | Function |
|---|---|---|
| 4644101160 | TRANSMISSION HOUSING | Main structural casing for gear train |
| 4644301323 | TRANSMISSION HOUSING | Alternate housing variant for WG201 |
| 4644301189 | THREADED BUSH | Provides wear-resistant thread for fasteners |
| 4475280043 | SCREW PLUG | Seals hydraulic test ports |
| 0634306198 | O-RING | Prevents fluid leakage at joints |
| 0730365067 | TYPE PLATE | Identification tag for transmission model |
| 4644301161 | COVER PLATE | Encloses valve body access area |
| 0636100621 | HEXAGON SCREW | Secures cover plate to housing |
| 0631610020 | SET SCREW | Locks adjustment positions |
| 0501218540 | BREATHER | Equalizes internal pressure |
