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- Briggs & Stratton 30737
- Firman WT05571
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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 | Briggs & Stratton 30737 | Firman WT05571 |
|---|---|---|
| General | ||
| Product type | Generator | Generator |
| Fuel | Gasoline | Tri-Fuel |
| Inverter | No | Yes |
| Parallel capable | No | Yes |
| RV ready | No | Yes |
| Running watts | 5000 W | Winner: Winner: 5500 W |
| Starting watts | 6250 W | Winner: Winner: 6850 W |
| Noise (lower limit) | 0 dB | Winner: Winner: 67 dB |
| Weight | 184 lbs | Winner: Winner: 131.4 lbs |
| Run time @50% load | Winner: Winner: 12 h | Not available |
| Run time @25% load | Not available | 14.5 h |
| Fuel tank | 7.5 gal | 5.3 gal |
| Fuel gauge | Yes | Yes |
| Approx. dimensions (L × W × H) | 29 x 26 x 27 | 27.6 x 21.3 x 22.6 |
| Electrical | ||
| Voltage (AC) | 120/240 | 120/240 |
| Voltage (DC) | Not available | 12 |
| GFCI outlets | Yes | Yes |
| Covered outlets | Yes | Yes |
| Automatic Voltage Regulation | Yes | Yes |
| THD | Not available | 3 % |
| Engine | ||
| Engine | Briggs & Stratton PowerBuilt™ OHV 4-stroke | 322 cc OHV 4-stroke, cast iron sleeve. |
| Alternator | Not available | Not available |
| Starting system | Recoil | Recoil, Electric |
| Warranty | ||
| Warranty | 2 years | 3 years |
| Power by fuel | ||
| Gasoline | Not available | Not available |
| Running watts | 5000 W | 5500 W |
| Starting watts | 6250 W | 6850 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 | Not available | 14.5 h |
| Natural gas | Not available | Not available |
| Running watts | Not available | 4500 W |
| Starting watts | Not available | 5500 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 | Not available | Not available |
| Run time @25% load | Not available | Not available |
| Propane | Not available | Not available |
| Running watts | Not available | 5000 W |
| Starting watts | Not available | 6250 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 | Not available | Not available |
| Run time @25% load | Not available | 9.5 h |
| Other | ||
| Data center | Not available | Not available |
| Indicators | false | Not available |
| Compliance | N/A | EPA, ANSI/PGMA G300-2023 |
| Security | Not available | Not available |
| Spark arrestor | Yes | Yes |
| Neutral | Not available | Bonded to frame |
| UPC | 11675307370 | 840876155714 |
| Core / High-priority specs | ||
| Running Watts (Gasoline) | 5000 | 5500 |
| Running Watts (Propane) | Not available | 5000 |
| Running Watts (Natural Gas) | Not available | 4500 |
| Starting Watts (Gasoline) | 6250 | 6850 |
| Starting Watts (Propane) | Not available | 6250 |
| Starting Watts (Natural Gas) | Not available | 5500 |
| Runtime @ 50% Load (Gasoline) | 12 | Not available |
| Runtime @ 25% Load (Gasoline) | Not available | 14.5 |
| Runtime @ 25% Load (Propane) | Not available | 9.5 |
| AC Outlet Types | 2x Duplex 120V 20A (5-20R) GFCI 1x Duplex 120V 20A (5-20R) 1x 120/240V 30A (L14-30R) | 1x Duplex 120V 20A (5-20R) GFCI; 1x 120V 30A (TT-30R); 1x 120/240V 30A (L14-30R); 1x 120/240V 50A (14-50R) |
| Electrical & power | ||
| Frequency | 60 | 60 |
| Engine & construction | ||
| Engine Type | Briggs & Stratton PowerBuilt™ OHV 4-stroke | OHV 4-stroke |
| Engine Displacement | 389 | 322 |
| Cylinder Sleeve | Not available | cast iron sleeve |
| Runtime & fuel system | ||
| Runtime @ 25% Load (Gasoline) | Not available | 14.5 |
| Runtime @ 50% Load (Gasoline) | 12 | Not available |
| Safety & compliance | ||
| Overload Protection System | Low oil and overload protection | Low oil and overload protection, CO monitoring |
| Low Oil Protection | Yes | Yes |
| Carbon Monoxide Monitoring | Yes | Yes |
| Included equipment | ||
| Starting Components | Not available | Oil, funnel, tool kit, propane hose, and battery |
| Included Accessories | Oil and wheel kit | Oil, funnel, tool kit, propane hose, and battery |
| Warranty & identification | ||
| Commercial Warranty | Not available | 3 |
| Additional specs | ||
| Summary | The Briggs & Stratton 30737 is a 5000-watt gasoline generator built for homeowners and job site operators who need extended runtime without constant refueling. With 5000 running watts and 6250 peak watts, this unit can power a refrigerator, multiple lights, and power tools simultaneously, making it suitable for emergency backup or outdoor work. The 7.5-gallon fuel tank delivers 12 hours of runtime at half load, which means a full day of operation before refueling becomes necessary. This is a stationary-duty machine. At 184 pounds, it requires wheels or multiple people to move, so placement matters before startup. | The Firman WT05571 is a 5,500-watt tri-fuel generator that runs on gasoline, propane, or natural gas. On gasoline, it delivers 6,850 starting watts and 5,500 running watts, enough to power a full home electrical panel during an outage or run multiple job site tools simultaneously. On propane, output drops to 6,250 starting and 5,000 running watts. On natural gas, it falls to 5,500 starting and 4,500 running watts. This fuel flexibility means users can switch between sources based on availability, cost, or storage preference without buying multiple generators.
The tri-fuel capability makes this unit valuable for homeowners in regions with natural gas infrastructure, RV owners who can refill propane at any campground, and contractors who need to adapt to job site fuel availability. The 3 percent THD rating protects laptops, televisions, and other sensitive electronics from voltage spikes that damage circuits. At 67 decibels, the noise level sits between a typical conversation and heavy traffic, making it suitable for residential neighborhoods but audible enough that neighbors will know it is running. |
- Most PowerfulFirman WT055715500W running
- QuietestFirman WT0557167 dB
- Longest RuntimeBriggs & Stratton 3073712h at 50% load
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Briggs & Stratton 30737
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Firman WT05571
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