Overview
The ZF 4166.039.077 CONVERTER Torque Converter Assembly is a complete, factory-matched unit engineered for the WG 65 Series transmission family. This critical component sits between the engine flywheel and the transmission input shaft, converting engine torque into hydraulic energy to drive the planetary gears. As a direct replacement for the OEM assembly, the SKU 4166.039.077 ensures precise lock-up clutch engagement and smooth power delivery under heavy loads. The unit integrates seamlessly with the 4616101065: TRANSMISSION HOUSING to maintain correct alignment and fluid sealing.
Symptoms of Failure
- Torque converter shudder or vibration during acceleration — Worn internal stator bearings or damaged clutch friction material cause noticeable shaking, especially at low speeds or under moderate throttle.
- Delayed or harsh lock-up engagement — When the converter fails to lock properly, you may experience a sudden jolt or a prolonged slip between 40–60 km/h, often accompanied by elevated transmission fluid temperatures.
- Dark, burnt-smelling transmission fluid — Internal wear generates excessive heat and debris, turning the fluid a dark brown or black color with a distinct burnt odor, indicating imminent converter failure.
- Intermittent loss of power or gear slipping — A failing torque converter cannot maintain hydraulic pressure, leading to erratic gear engagement and a feeling of the transmission “falling out” of gear under load.
Technical Specifications
| Specification | Value |
|---|---|
| Part Number | 4166.039.077 |
| Assembly Type | Complete Torque Converter (with lock-up clutch) |
| Overall Diameter | ~320 mm (12.6 in) |
| Overall Length | ~180 mm (7.1 in) |
| Weight | ~14.5 kg (32.0 lbs) |
| Housing Material | High-strength cast iron / steel |
| Impeller & Turbine Material | Forged steel with hardened surfaces |
| OEM Reference | ZF 4166.039.077 (direct OE replacement) |
| Seal Type | Viton O-ring (compatible with 0634313118: O-RING) |
Compatibility
This torque converter assembly is designed for ZF WG 65 Series transmissions, specifically the WG180 and WG200 models used in heavy-duty construction, mining, and agricultural equipment. It also fits select WG 65 variants in off-highway trucks and wheel loaders. The unit is a direct bolt-in replacement for the original converter and requires no modifications when paired with the correct 0636011038: HEXAGON SCREW and 0636011118: HEXAGON SCREW for mounting. For final torque specifications, always use the 0636016015: HEXAGON SCREW to secure the converter to the flexplate.
Related Components
| Part Number | Name | Function |
|---|---|---|
| 4616101065 | TRANSMISSION HOUSING | Encloses and supports the torque converter and gearset |
| 0636011038 | HEXAGON SCREW | Fastens converter to flexplate (M10 x 25 mm) |
| 0636011118 | HEXAGON SCREW | Secures housing cover (M12 x 30 mm) |
| 0636016015 | HEXAGON SCREW | Mounts converter to engine flywheel (M14 x 35 mm) |
| 0631306085 | CYLINDRICAL PIN | Aligns converter to housing during installation |
| 0634313118 | O-RING | Seals converter-to-housing fluid passage |
| 0636304019 | SCREW PLUG | Closes drain port on converter housing |
| 0634801152 | SEALING RING | Prevents oil leaks at converter hub |
| 0732611049 | FILTER INSERT | Traps debris in converter oil circuit |
| 0634303718 | O-RING | Seals converter-to-pump interface |
