Well technically, what works well in mud/snow is a "tracked" vehicle.
Of coarse, the surface you're on & tires make a difference.
That white Bronco above likely still has it's "front" wheel drive in tact & helping as well.
I'm guessing your factory dually is rear dr. only.
But then.., my bud stuck his Jeep Rubicon on a flat/dry trail..

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Had to turn-a-round, hook him up & pull him out.
Driver makes a big difference as well.

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