I wanted to rewatch an old movie but I can't find anything about it. I remember its title in Spanish only: "Los Quemadores" (The Burners?) I don't know how good or accurate this translation was.
This movie was probably filmed in the 70s or 80s (color movie).
In the story gasoline was not available anymore, except for the government. However, there were secret stockpiles that rich guys and other outliers had gathered before gasoline was banned. These outliers used to drive around in their old cars, in the desert. They also used to steal gasoline from each other, and escape from the government that wanted to get a hold on any remaining gas out there.
The plot has common ideas with Mad Max, but the story was probably located in the western United States, not Australia.