Overview
The ZF 4644.183.090 LOOSE PARTS kit is a critical service component designed specifically for the WG 180 series transmission. This OEM genuine assembly contains the essential loose hardware required to secure and seal internal transmission elements during a rebuild or overhaul. Positioned within the main gear train housing, this kit ensures that all fasteners, retainers, and small components remain properly torqued and aligned, preventing vibration-induced loosening. The SKU 4644.183.090 is factory-matched to ZF’s exacting tolerances, guaranteeing a direct fit without modification. When paired with a new 4644101249: TRANSMISSION HOUSING or a replacement 4644301402: TRANSMISSION HOUSING, this loose parts set restores the structural integrity of the WG180 assembly.
Symptoms of Failure
- Transmission fluid seepage at housing seams: Worn or missing loose parts can compromise the seal between the main case and the 4644301298: COVER PLATE, leading to slow oil leaks that worsen over time.
- Audible rattling or metallic clatter during gear engagement: Loose fasteners within the 4644.183.090 kit allow internal components to shift, creating noise under load.
- Intermittent gear slippage or delayed engagement: When the loose parts fail to secure the shift mechanism, hydraulic pressure can escape, causing erratic shifting behavior.
- Increased vibration at highway speeds: A degraded loose parts set can unbalance the rotating assembly, transmitting harshness through the driveline.
Technical Specifications
| Parameter | Specification |
|---|---|
| Part Number | 4644.183.090 |
| OEM Reference | ZF WG180 Series |
| Material Composition | Hardened steel with zinc plating (fasteners); nitrile rubber (seals) |
| Weight | 0.45 kg (1.0 lb) |
| Dimensions (L x W x H) | 120 mm x 80 mm x 30 mm |
| Torque Specification | 25 Nm (18.4 ft-lb) per fastener |
| Operating Temperature Range | -40°C to 120°C |
Compatibility
This OEM genuine part is engineered primarily for the ZF WG180 transmission series. It is also compatible with the WG200 and select WG160 variants that share the same housing bolt pattern and loose parts configuration. For optimal sealing, always install this kit with a fresh 0634306323: O-RING to prevent fluid bypass. The 4644.183.090 kit is not backward-compatible with older WG120 or WG150 models without adapter modifications.
Related Components
| Part Number | Name | Function |
|---|---|---|
| 4644101249 | TRANSMISSION HOUSING | Main structural case for gear train |
| 4644301402 | TRANSMISSION HOUSING | Alternate housing variant for WG180 |
| 4644301298 | COVER PLATE | Seals the rear of the transmission housing |
| 0634306323 | O-RING | Provides hydraulic seal between components |
| 0636305026 | SCREW PLUG | Closes fluid passages during service |
| 4644301279 | SCREEN SHEET | Filters debris from transmission fluid |
| 4644301088 | SEALING CAP | Prevents contamination of open ports |
| 4644159347 | SHIFT SYSTEM | Controls gear selection mechanism |
| 4475280036 | SCREW-IN SLEEVE | Provides threaded mounting point for sensors |
| 4644306511 | GEAR SHIFT HOUSING | Encloses the shift linkage assembly |
