From publisher blurb:
The D&D Gamma World rulebook and the Famine in Far-Go expansion both allow you to roll up vehicles as part of your starting gear but no rules are – provided on how to actually use them in the game, apart from a few brief details on their overland speeds and gas mileage.
So, then, here are house rules for vehicles in D&D Gamma World, along with stats for several different types of vehicles for your games.
Note that cars, motorcycles, and other Ancient technology vehicles have a combat speed that is lower than their overland speed. This is intentional and meant to represent the speeds at which meaningful fights can take place. In actuality, a sportscar traveling at 75 miles per hour would move approximately 150 squares in one round.