Overview
The ZF 6073.015.149 EST 37 A is a critical electro-hydraulic control unit specifically engineered for the WG 230 Series transmission. This OEM genuine part, identified by SKU 6073.015.149, serves as the primary interface between the transmission’s electronic control system and its hydraulic actuation circuits. Positioned within the valve body assembly, it modulates oil pressure to engage and disengage clutches and brakes, ensuring precise shift timing and torque delivery. When paired with the 4657101082: TRANSMISSION HOUSING, this component forms the core of the shift control system, directly influencing drivability and fuel efficiency in heavy-duty commercial vehicles.
Symptoms of Failure
When the ZF 6073.015.149 EST 37 A begins to degrade, operators will notice distinct performance issues. Delayed or harsh gear engagement is a primary indicator, often accompanied by a noticeable “clunk” during shifts. Intermittent loss of forward or reverse gears occurs as internal solenoids fail to maintain hydraulic pressure. Transmission fluid contamination from worn internal seals can cause erratic shifting patterns, while persistent diagnostic trouble codes (DTCs) related to solenoid circuit faults will illuminate the check engine light. These symptoms typically worsen under load or during temperature extremes.
Technical Specifications
| Parameter | Specification |
|---|---|
| Part Number | 6073.015.149 |
| OEM Reference | ZF EST 37 A |
| Material | High-grade aluminum alloy with steel solenoid cores |
| Weight | 2.8 kg (6.2 lbs) |
| Operating Voltage | 12V / 24V DC |
| Seal Type | Nitrile rubber O-rings (included) |
| Torque Specs | Mounting bolts: 25 Nm |
Compatibility
This EST 37 A control unit is designed for the ZF WG 230 Series transmission family. It is also compatible with the WG180, WG200, and WG210 models when used in conjunction with the correct 4657201166: HOUS.FRONT SECT and 4657201170: HOUSING REAR PART. For applications requiring a complete rear housing assembly, the 4657298102: HOUSING REAR SECTION is also required. Always verify your transmission serial number before installation, as variations exist between early and late production units.
Related Components
| Part Number | Name | Function |
|---|---|---|
| 4657101082 | TRANSMISSION HOUSING | Main structural casing for gear train |
| 4657201166 | HOUS.FRONT SECT | Front section housing for pump and converter |
| 4657201170 | HOUSING REAR PART | Rear section for output shaft support |
| 4657298102 | HOUSING REAR SECTION | Alternate rear housing variant |
| 0631306816 | CYLINDRICAL PIN | Alignment dowel for housing assembly |
| 0636100801 | CAP SCREW | Fastener for valve body mounting |
| 4656301148 | FIXING PLATE | Retainer plate for solenoid harness |
| 4657301032 | SCREEN SHEET | Fine mesh filter for hydraulic circuit |
| 4657301033 | SCREEN SHEET | Coarse mesh pre-filter |
| 0636100803 | CAP SCREW | Fastener for housing cover |
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