Overview
The ZF 4644.183.026 LOOSE PARTS kit is a critical OEM genuine service component designed specifically for the WG 180 Series transmission. This assembly consolidates essential wear items that maintain hydraulic integrity and mechanical alignment within the gear train. As a loose parts set, it includes the necessary fasteners, spacers, and retaining elements that secure internal assemblies against vibration and thermal cycling. The SKU 4644.183.026 is factory-matched to ZF’s exacting tolerances, ensuring that when installed alongside a 4644101249: TRANSMISSION HOUSING or a 4644301402: TRANSMISSION HOUSING, the entire clutch and planetary assembly remains precisely located. Without this kit, even a new housing cannot guarantee leak-free operation or correct gear engagement.
Symptoms of Failure
- Intermittent gear slippage under load: When the loose parts wear or loosen, the clutch pack clearance increases, causing the transmission to slip during acceleration or hill climbing.
- External oil seepage at housing joints: Degraded sealing elements within the 4644.183.026 kit allow transmission fluid to weep past the 0634306323: O-RING interfaces, leaving visible drips on the bell housing.
- Abnormal driveline noise during shifting: Loose retaining hardware permits axial play in the shaft assembly, producing a distinct clunk or whine when the transmission transitions between forward and reverse.
- Erratic shift timing: As the loose parts degrade, valve body alignment shifts, causing delayed or harsh engagement that can be mistaken for solenoid failure.
Technical Specifications
| Parameter | Value |
|---|---|
| Part Number | 4644.183.026 |
| Product Type | Loose Parts Kit (OEM Genuine) |
| Material Composition | Steel retainers, nitrile rubber seals, zinc-plated hardware |
| Weight (approx.) | 0.45 kg (1.0 lb) |
| OEM Reference | ZF 4644.183.026 |
| Operating Temperature Range | -40°C to +120°C |
| Compatible Housing | 4644301298: COVER PLATE and related housings |
Compatibility
This OEM genuine part is engineered primarily for the ZF WG 180 Series, including all WG180 variants (WG180, WG180-1, WG180-2). It also fits select WG200 models that share the same loose parts architecture, particularly those using the 4644301298: COVER PLATE interface. For applications requiring a complete seal renewal, always pair this kit with a fresh 0634306323: O-RING to prevent fluid bypass. The 4644.183.026 is not backward-compatible with older WG150 or WG160 transmissions without adapter modifications.
Related Components
| Part Number | Name | Function |
|---|---|---|
| 4644101249 | TRANSMISSION HOUSING | Main structural casing for gear train |
| 4644301402 | TRANSMISSION HOUSING | Alternate housing variant for WG180 |
| 4644301298 | COVER PLATE | Seals and protects internal components |
| 0634306323 | O-RING | Hydraulic seal for housing joints |
| 0636305026 | SCREW PLUG | Closes fluid passages during service |
| 4644301279 | SCREEN SHEET | Filters debris from hydraulic fluid |
| 4644301088 | SEALING CAP | Prevents contamination of open ports |
| 4644159347 | SHIFT SYSTEM | Controls gear selection mechanism |
| 4475280036 | SCREW-IN SLEEVE | Provides threaded mounting point |
| 4644306511 | GEAR SHIFT HOUSING | Encloses shift linkage assembly |
