Overview
The ZF 4644.109.014 PARKING BRAKE is a critical safety and holding component engineered specifically for the WG 180 Series transmission. This OEM genuine part engages a mechanical locking mechanism on the output shaft, ensuring the vehicle remains stationary when parked, even on steep inclines. Located within the rear section of the transmission housing, it integrates directly with the shift system to provide positive engagement. The SKU 4644.109.014 is the definitive replacement for original equipment, guaranteeing precise fitment and long service life. When paired with a robust TRANSMISSION HOUSING, this parking brake assembly maintains the structural integrity required for heavy-duty industrial applications.
Symptoms of Failure
Recognizing early signs of wear in the ZF 4644.109.014 can prevent costly driveline damage. Look for these specific failure symptoms:
- Vehicle rollback on slopes: A worn parking brake fails to hold the output shaft, causing the vehicle to creep or roll when parked on an incline.
- Grinding or clicking noises during engagement: Damaged internal pawls or springs produce audible metallic sounds when the brake is applied or released.
- Intermittent brake release: The lever or actuator may feel loose or fail to lock into position, leading to unexpected disengagement.
- Oil contamination near the brake drum: A failing seal allows transmission fluid to mix with brake components, reducing friction and causing slippage.
Technical Specifications
| Parameter | Specification |
|---|---|
| Part Number | 4644.109.014 |
| Type | Mechanical Parking Brake Assembly |
| Material | Hardened Steel / Cast Iron |
| Weight | 2.8 kg (6.2 lbs) |
| OEM Reference | ZF 4644.109.014 |
| Mounting Torque | 45 Nm |
| Compatible Fluid | ZF EcoFluid or Dexron III |
Compatibility
This parking brake is primarily designed for the WG 180 Series transmission, commonly found in heavy-duty trucks, buses, and construction equipment. It is also compatible with the WG 200 series when used with the appropriate HOUSING adapter. For proper identification, always verify the TYPE PLATE on your transmission. The assembly requires a GROOVED STUD for secure mounting to the shift system. Additional compatible models include WG 160 and WG 180-2 variants, though cross-referencing the serial number is recommended.
Related Components
| Part Number | Name | Function |
|---|---|---|
| 4644101080 | TRANSMISSION HOUSING | Encloses and supports all internal transmission components |
| 4644301333 | HOUSING | Rear housing section for parking brake integration |
| 0730365125 | TYPE PLATE | Identification plate with transmission model and serial number |
| 0631311009 | GROOVED STUD | Fastening stud for brake assembly mounting |
| 0636305019 | SCREW PLUG | Seals hydraulic passages in the housing |
| 4644301247 | THREADED BUSH | Provides threaded anchor point for brake linkage |
| 0634303485 | O-RING | Prevents fluid leaks at housing joints |
| 4644106055 | SHIFT SYSTEM | Controls gear selection and brake engagement |
| 4642306050 | COVER PLATE | Protects internal brake components from debris |
| 4644306464 | GASKET | Seals the parking brake cover plate |
