Caterpillar G3408 vs Generac SG250
The Caterpillar G3408 and Generac SG250 are both natural gas generator engines in a similar power class. Both are rated at roughly 313 kVA. Displacement is 18 L versus 14.2 L. The table below compares their full specifications side by side.
| Specification | Caterpillar G3408 | Generac SG250 |
|---|---|---|
| Headline rating | 313 kVA | 313 kVA |
| Standby (50 Hz) | — | — |
| Prime (50 Hz) | 250 kWe | — |
| Standby (60 Hz) | — | 250 kWe |
| Prime (60 Hz) | — | 225 kWe |
| Displacement | 18 L | 14.2 L |
| Configuration | V8 | L6 |
| Cylinders | 8 | 6 |
| Rated speed | 1,500 RPM | 1,800 RPM |
| Fuel | Natural Gas | Natural Gas |
| Cooling | Liquid-Cooled | Liquid-Cooled |
| Emissions | U.S. EPA Stationary | U.S. EPA Stationary |
| Dry weight | — | — |
| Origin | United States | United States |
Choosing between Caterpillar G3408 and Generac SG250
Use this comparison as an engineering shortlist, then confirm the complete generator package against load profile, voltage, 50/60 Hz frequency, duty class, emissions rules, cooling margin, altitude, ambient temperature, enclosure design, controller features, and alternator sizing.