It will be necessary to contact the manufacturer for that information. Note also that they will provide complete shipping data including center of gravity (balance point) and other data.
3 megawatt generators by themselves can weigh as little as 15,000 lbs and as much as 45,000 lbs. Add that to the weight of the engine, transmission, and speed reduction gearing, and you will see the task ahead of you.
Do not be discouraged. Just realize that you may need to ship it on more than one truck.
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