Overview
The ZF 4681.084.027 4 BP 230 BASICPOWER Transmission Assembly is a complete, factory-grade unit engineered for heavy-duty commercial and industrial powertrains. This assembly serves as the core hydraulic-mechanical module within the BP 230 series, integrating the torque converter, planetary gear sets, and clutch packs into a single, pre-assembled package. Designed for direct replacement, the SKU 4681.084.027 eliminates the need for piecemeal component sourcing, ensuring precise alignment and OEM-specified clearances. It functions as the primary power transfer interface between the engine and the driveline, converting high-torque input into controlled output across multiple gear ratios. This unit is critical for maintaining operational uptime in buses, construction vehicles, and specialized off-road equipment.
Symptoms of Failure
When the ZF 4681.084.027 assembly begins to degrade, operators will notice distinct performance declines. Recognizing these signs early prevents catastrophic driveline damage.
- Delayed or harsh gear engagement: A worn clutch pack or valve body within the assembly causes a noticeable lag when shifting from Neutral to Drive or Reverse, often accompanied by a jarring thud.
- Progressive oil seepage at the bell housing: Degraded seals around the torque converter hub or pump drive lead to fluid loss, visible as drips or wetness near the transmission-to-engine interface.
- Intermittent gear slipping under load: During uphill climbs or heavy acceleration, the transmission may momentarily lose power delivery as internal clutches fail to hold torque, causing RPM flare without corresponding speed increase.
- Unusual whining or grinding noises: Bearing wear or planetary gear damage produces a metallic whine that increases with engine RPM, indicating imminent internal failure of the rotating assembly.
Technical Specifications
| Specification | Detail |
|---|---|
| Part Number / SKU | 4681.084.027 |
| Assembly Type | Complete Unit (4 BP 230 BASICPOWER) |
| Overall Length | Approx. 620 mm |
| Dry Weight | ~145 kg (320 lbs) |
| Housing Material | High-strength aluminum alloy (A356-T6) |
| Torque Converter Diameter | 310 mm |
| Clutch Pack Count | 4 (Forward, Reverse, 2nd/3rd gear) |
| OEM Reference | ZF BP 230 / BP 210 Series |
| Fluid Capacity (assembly) | 12.5 liters (approx.) |
Compatibility
This assembly is specifically engineered for the ZF BP 210 and BP 230 transmission families. It directly replaces units in the following models and their derivatives:
- ZF WG180 – Used in mid-size city buses and refuse trucks.
- ZF WG200 – Common in intercity coaches and heavy distribution vehicles.
- ZF 4 HP 220 – Found in older construction loaders and mobile cranes.
- ZF 4 BP 230 – Standard in modern fire trucks and airport ground support equipment.
Always verify the serial number on your existing unit’s data plate. The 4681.084.027 is a complete assembly and does not include the external electronic control module (ECU) or shift selector. For model-specific fitment questions, consult your vehicle’s OEM service manual or a certified ZF distributor.
