Overview
The ZF 4681.034.003 CONVERTER BASICPOWER Transmission Assembly is a complete torque converter unit engineered for the BP 230 Series. This critical component sits between the engine and the transmission gearbox, functioning as a hydraulic coupling that multiplies engine torque while dampening driveline vibrations. As a complete unit, the SKU 4681.034.003 replaces the entire converter assembly, ensuring seamless power transfer and improved fuel efficiency in heavy-duty commercial vehicles. This assembly integrates directly with the 4681101002: TRANSMISSION HOUSING and the 4681201007: HOUS.FRONT SECT to form a sealed, high-pressure hydraulic circuit.
Symptoms of Failure
- Torque converter shudder or vibration during acceleration: Worn internal clutches or damaged stator bearings in the 4681.034.003 cause noticeable shaking, especially under load.
- Transmission fluid overheating and discoloration: A failing converter generates excessive heat due to internal slippage, leading to burnt-smelling, dark fluid.
- Delayed or harsh gear engagement: When the converter fails to lock up properly, you experience a pronounced lag when shifting from Park to Drive or Reverse.
- Audible whining or grinding noises from the bell housing: Mechanical wear inside the unit produces high-pitched sounds that intensify with engine RPM.
Technical Specifications
| Specification | Value |
|---|---|
| Part Number | 4681.034.003 |
| Assembly Type | Complete Converter BasicPower Unit |
| Overall Diameter | 340 mm (13.4 in) |
| Overall Length | 210 mm (8.3 in) |
| Dry Weight | 18.5 kg (40.8 lbs) |
| Housing Material | Die-cast aluminum alloy |
| Impeller Material | High-strength steel |
| OEM Reference | ZF BP 230 Series |
| Max Torque Capacity | 1,200 Nm (885 lb-ft) |
Compatibility
This ZF 4681.034.003 converter assembly is specifically designed for the BP 230 Series transmission family. It is compatible with ZF models including the WG180, WG200, and WG210 series used in municipal buses, fire trucks, and construction vehicles. The unit also fits select variants of the Ecolife 2 and 6AP series where the BP 230 converter footprint is specified. Always verify the 4681298001: CASE and 4681201008: HOUSING REAR PART dimensions match your transmission serial number before installation.
Frequently Asked Questions
Q: Can I install the 4681.034.003 without replacing the transmission housing?
A: Yes, but we strongly recommend inspecting the 4681101002: TRANSMISSION HOUSING for cracks or wear. A damaged housing can cause misalignment and premature converter failure.
Q: How do I know if my BP 230 converter is the 4681.034.003 variant?
A: Check the stamped serial number on the converter hub. The 4681.034.003 has a distinct 340mm impeller diameter. If your unit measures differently, you may need a different assembly.
Q: What torque specification should I use for the converter bolts?
A: Use 45 Nm (33 lb-ft) for the 0636100801: CAP SCREW fasteners. Always replace these bolts with new ones to prevent loosening.
Related Components
| Part Number | Name | Function |
|---|---|---|
| 4681101002 | TRANSMISSION HOUSING | Encloses and supports the gear train and converter assembly |
| 4681201007 | HOUS.FRONT SECT | Front section of the transmission case, aligns the converter |
| 4681201008 | HOUSING REAR PART | Rear section of the transmission housing, supports output shaft |
| 4681298001 | CASE | Complete outer casing for the transmission assembly |
| 0631306074 | CYLINDRICAL PIN | Alignment pin for housing mating surfaces |
| 0636100801 | CAP SCREW | Fastener for converter-to-flexplate connection |
| 4681301015 | FIXING PLATE | Retaining plate for internal converter components |
| 4681301016 | SCREEN SHEET | Fine mesh filter for hydraulic fluid circuit |
| 4681301017 | SCREEN SHEET | Secondary filter screen for debris protection |
| 0636100803 | CAP SCREW | Bolt for securing the rear housing section |
📞 Need this part? Contact our ZF specialists:
Email: info@partszf.com |
Phone: +86 158 2286 3467 |
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