Description
Product Introduction
The Woodward 47373-01M is a 3-N-1 gauge assembly packing six functions into one 4-3/8″ (111 mm) dial, contoured for 1947-53 Chevy/GMC truck dashes. It handles Speedo, Tach, Oil, Fuel, Water, and Volts, replacing a multi-hole panel with one NVU Direct Drive unit.
This “M” variant, Woodward 47373-01M, defaults the fuel logic to 240-33Ω (GM standard) and features a metric 240 kph speedo scale overlay. The black face with white graphics maintains a classic look. Needle settling hits <1.5 s post 12 Vdc power-up.
Key Technical Specifications
| Parameter | Value |
|---|---|
| Function Count | 6-in-1 (Speed, Tach, Oil, Fuel, Water, Volts) |
| Mounting Diameter | 4-3/8 in (111 mm) |
| Outer Diameter | 4-11/16 in (119 mm) |
| Speed Range | 0-140 mph (Programmable, 240 kph metric scale) |
| Tach Range | 0-8000 RPM (Discrete input) |
| Oil Pressure Range | 0-100 psi |
| Fuel Level | 240-33Ω Default (Programmable to 0-90Ω) |
| Water Temp Range | 100-250 °F (verify with OEM datasheet) |
| Voltmeter Range | 8-18 Vdc |
| Face Color | Black |
| Graphics | White / Wraparound Deco |
| Pointer Color | Red |
| Bezel | Polished stainless (Truck-specific contour) |
| Lens | Domed glass |
| Wiring | NVU Direct Drive (Single 12 Vdc tap) |
Woodward 47371-01
Quality Control Process (Engineer’s Perspective)
- Incoming Verification: Match NVU Woodward 47373-01M serials to the packing slip. Inspect the truck-contour bezel for swirl marks and check the dome glass for trapped debris near the rim.
- Live Functional Test: Apply 12 Vdc to the Packard plug. Inject 60 Hz to the tach lead. All six pointers sweep full scale; verify the OLED for segment integrity during the self-test routine.
- Electrical Parameter Test: Sweep a pot on the fuel pins using a Fluke 115. Confirm ADC linearity within 2%—default 240-33Ω scaling should read “Full” at low resistance (verify with OEM datasheet).
- Firmware Verification: Trigger one-mile calibration via the remote button. Photograph the OLED confirming PPM lock—well, technically it needs firmware v3.2+ for push-button config.
- Final QC & Packaging: Cradle the 111 mm unit in die-cut anti-static foam. Coil the harness loosely. Apply “QC Passed – 24hr Burn-in” labels with the date before boxing.
Replacement Pitfall Guide
❗ Fuel Scale Default: The Woodward 47373-01M defaults to 240-33Ω. Swapping from a standard NVU kit (0-90Ω) without recalibrating the button shows Empty when the tank is full.
❗ Bezel Contour: This uses a specific 1947-53 Chevy/GMC bezel shape. Dropping it into a flat 4-3/8″ hole gaps the lens, causing glare off the bezel lip at night.
❗ Tach Signal Voltage: The driver accepts 12 V coil or 5 V PCM. Feeding unregulated MSD outputs without the inline filter (included) causes needle bounce above 5000 RPM.
❗ Shared Ground Plane: Six functions share one sensor ground on the speedo logic. If your oil sender body grounds to the block andhas a case ground, fuel readings drift.
❗ ESD to OLED: The trip display driver is static-sensitive. Discharge to chassis ground before plugging the Packard in dry shop air—though your mileage may vary on humidity control.
Keep these in mind and you’ll cut 90% of rework time.
Woodward 47371-01
Compatibility Matrix & Benchmarks
- Woodward 47373-01M → Woodward 47373-01 : Needs Adaptation — Fuel curve default (240-33Ω vs 0-90Ω) + Metric overlay
- Woodward 47373-01M → Woodward 47372-01M : Direct — Face color swap (Black vs Beige) + Shared 240-33Ω default
- Woodward 47373-01M → Woodward 37205-02 : Needs Adaptation — 37205 is a 2-gauge kit; this is a single 3-N-1 unit
- Sweep Response: < 1.5 seconds (0-140 mph / 0-8000 RPM step)
- Signal Input Range: 2,000 to 40,000 PPM (Speedo), 0.5-333 Hz (Tach)
- Display Update Rate: 10 Hz (OLED Trip/ODOM)
