Compare Generators Side-by-Side
Select up to 4 generators to compare specs, power output, noise levels, runtime and more. Your compare URL is shareable.
- DuroStar DS4000S
- Firman W03381
Quick charts
Each chart uses its own Y-axis scale (so numbers are comparable within a chart).
Running watts
W
Starting watts
W
Noise
dB
Runtime @50%
h
Running watts by fuel
Shows how output changes across gasoline/propane/natural gas (when available).
| Specification | DuroStar DS4000S | Firman W03381 |
|---|---|---|
| General | ||
| Product type | Generator | Generator |
| Fuel | Gasoline | Gasoline |
| Inverter | No | Yes |
| Parallel capable | No | Yes |
| RV ready | No | Yes |
| Running watts | Winner: Winner: 3300 W | Winner: Winner: 3300 W |
| Starting watts | Winner: Winner: 4000 W | 3650 W |
| Noise (lower limit) | 69 dB | Winner: Winner: 58 dB |
| Weight | 92 lbs | Winner: Winner: 87 lbs |
| Run time @50% load | Winner: Winner: 12 h | Not available |
| Run time @25% load | 26 h | 10 h |
| Fuel tank | 4 gal | 1.8 gal |
| Fuel gauge | Yes | No |
| Approx. dimensions (L × W × H) | 23 x 18 x 17.5 | 23.2 x 17.8 x 17.9 |
| Electrical | ||
| Voltage (AC) | 120 | 120 |
| Voltage (DC) | Not available | 12 |
| GFCI outlets | No | No |
| Covered outlets | No | Yes |
| Automatic Voltage Regulation | Yes | Yes |
| THD | Not available | 3 % |
| Engine | ||
| Engine | DuroStar OHV 4-stroke | 193 cc Firman Max-Pro Series OHV 4-Stroke, Cast Iron Sleeve |
| Alternator | Not available | Not available |
| Starting system | Recoil | Recoil |
| Warranty | ||
| Warranty | 3 years | 3 years |
| Power by fuel | ||
| Gasoline | Not available | Not available |
| Running watts | 3300 W | 3300 W |
| Starting watts | 4000 W | 3650 W |
| Running amps (120V) | Not available | Not available |
| Running amps (240V) | Not available | Not available |
| Peak amps (120V) | Not available | Not available |
| Peak amps (240V) | Not available | Not available |
| Run time @50% load | 12 h | Not available |
| Run time @25% load | 26 h | 10 h |
| Other | ||
| Data center | Not available | Not available |
| Indicators | true | true |
| Compliance | CARB, EPA | CARB, EPA |
| Security | Not available | Not available |
| Spark arrestor | Yes | Yes |
| Neutral | Floating | Floating |
| UPC | 811640011840 | 840876133811 |
| Core / High-priority specs | ||
| Running Watts (Gasoline) | 3300 | 3300 |
| Starting Watts (Gasoline) | 4000 | 3650 |
| Runtime @ 50% Load (Gasoline) | 12 | Not available |
| Runtime @ 25% Load (Gasoline) | 26 | 10 |
| AC Outlet Types | 1x Duplex 120V 20A (5-20R); 1x 120V 30A (L5-30R) | 1x Duplex 120V 20A (5-20R); 1x 120V 30A (TT-30R) |
| Electrical & power | ||
| Frequency | 60 | 60 |
| Engine & construction | ||
| Engine Type | OHV 4-stroke | OHV 4-Stroke |
| Engine Displacement | 208 | 193 |
| Cylinder Sleeve | Not available | Cast iron sleeve |
| Engine Oil Type | 10W-30 | 10W-30 |
| Runtime & fuel system | ||
| Runtime @ 25% Load (Gasoline) | 26 | 10 |
| Runtime @ 50% Load (Gasoline) | 12 | Not available |
| Safety & compliance | ||
| Overload Protection System | Low oil and overload protection | Low oil and overload protection |
| Low Oil Protection | Yes | Yes |
| Carbon Monoxide Monitoring | No | No |
| Included equipment | ||
| Starting Components | Not available | Recoil |
| Included Accessories | Funnel and tool kit | Oil, funnel, tool kit, and battery charging cables |
| Warranty & identification | ||
| Commercial Warranty | Not available | 3 |
| Additional specs | ||
| Summary | The DuroStar DS4000S is a 3,300-watt gasoline generator built around a DuroStar OHV 4-stroke engine that delivers 4,000 peak watts for startup surges. This wattage range powers essential household appliances, power tools, and small job site equipment simultaneously. A single person can operate it because the recoil starting system requires only manual pull-cord engagement, though the 92-pound weight means transport over distance demands planning. The 4-gallon fuel tank runs 26 hours at 25 percent load or 12 hours at 50 percent load, making it suitable for extended outages or multi-day outdoor use without constant refueling. EPA and CARB compliance clears this unit for all 50 states. | The Firman W03381 is a 3300-watt inverter generator built around a 193cc OHV 4-stroke engine with a cast iron sleeve. This wattage puts it in the mid-range portable segment, capable of powering a refrigerator, microwave, and several household circuits simultaneously, or running a single large tool on a job site. The 3650-watt starting capacity handles the inrush demand of compressors and air conditioning units. Because the W03381 runs on gasoline with a 1.8-gallon tank, users will find a 10-hour runtime at 25% load, which translates to roughly 2.5 hours of continuous full-load operation before refueling becomes necessary. The inverter topology and 3% THD output mean sensitive electronics like laptops, phones, and televisions receive stable, clean power without risk of damage. At 58 decibels, this generator operates at a volume comparable to normal conversation, making it suitable for residential neighborhoods and RV parks where noise restrictions apply. |
- Most PowerfulDuroStar DS4000S3300W running
- QuietestFirman W0338158 dB
- Longest RuntimeDuroStar DS4000S12h at 50% load
Where to buy
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DuroStar DS4000S
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Firman W03381
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