It'll make all the difference in the world. The right tires help and most of all make sure your rear axles articulate enough to keep the tires on the ground. A stock unmodified Tamiya rear suspension won't do it. My 6X6 Quarry dump truck has a custom rear suspension and all the axles locked. It'll go where no one would take a 1:1 dump truck. It doesn't steer well enough to run indoors but does fine in wide open spaces outside.
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