Overview
The ZF 4644.109.202 PARKING BRAKE is a critical safety component engineered specifically for the WG 200 series transmission. This OEM genuine part engages mechanically to lock the output shaft, preventing vehicle roll when parked or during service operations. Positioned within the rear housing assembly, the parking brake interfaces directly with the 4644101212: TRANSMISSION HOUSING and the 4644301221: TRANSMISSION HOUSING to ensure secure mounting and alignment. The SKU 4644.109.202 is manufactured to ZF’s original tolerances, guaranteeing reliable holding torque and long service life in heavy-duty industrial applications.
Symptoms of Failure
- Vehicle roll on incline: A worn parking brake fails to hold the transmission output shaft stationary, causing the vehicle to creep or roll even when the brake lever is fully engaged.
- Grinding or scraping noise: Deteriorated brake linings or seized actuation mechanisms produce metallic grinding sounds during engagement or disengagement, often mistaken for gear noise.
- Intermittent brake release: Internal spring fatigue or corrosion prevents the parking brake from fully disengaging, leading to drag, overheating, and premature wear of adjacent components like the 0634306531: O-RING seals.
- Oil contamination near brake assembly: Leaking seals allow transmission fluid to reach the brake friction surfaces, reducing holding force and causing slippage under load.
Technical Specifications
| Parameter | Specification |
|---|---|
| Part Number | 4644.109.202 |
| OEM Reference | ZF 4644.109.202 |
| Material | High-strength steel with friction lining |
| Weight | 2.8 kg (6.2 lbs) |
| Overall Diameter | 210 mm |
| Mounting Bolt Pattern | 4 x M10 on 160 mm PCD |
| Max Holding Torque | 1,200 Nm |
| Operating Temperature Range | -20°C to +120°C |
Compatibility
This parking brake is primarily designed for the ZF WG 200 series, but it also fits select WG 180 and WG 190 variants where the output shaft housing uses the same bolt pattern and spline interface. Always verify the transmission serial number against the OEM parts list. The brake assembly mounts directly to the 0730365067: TYPE PLATE area for correct identification, and it requires the 0631311009: GROOVED STUD for proper alignment during installation. For WG 200 models built after 2015, confirm housing revision compatibility.
Related Components
| Part Number | Name | Function |
|---|---|---|
| 4644101212 | TRANSMISSION HOUSING | Main structural casing for gear train |
| 4644301221 | TRANSMISSION HOUSING | Rear housing section for output shaft |
| 0730365067 | TYPE PLATE | Identification tag for transmission model |
| 0631311009 | GROOVED STUD | Alignment dowel for brake assembly |
| 4644303060 | COVER PLATE | Seals rear housing opening |
| 4644303061 | COVER PLATE | Alternate cover plate variant |
| 4644221031 | SCREEN TUBE | Oil filter screen for lubrication circuit |
| 0634306531 | O-RING | Seal for housing joint |
| 0634306525 | O-RING | Seal for brake actuator bore |
| 0636305026 | SCREW PLUG | Drain or fill port plug |
