Am I the only one surprised that nuclear-powered snow cruisers weren't used in Antarctic exploration, during the height of the atomic age? Maybe RTGs just don't produce enough power.
They were used by the soviets for unmanned arctic lighthouses, but even the largest RTGs only put out a couple hundred watts of electrical power (a small fraction of what this vehicle would need).
RTGs definitely don't put out enough power for a vehicle. They put out only tens of watts of electrical power. So for the expense and weight they'd be a really complicated battery for the radio.