[Coolhand]

Do you vehicle enthusiasts or people in the industry have a feeling for what drives the gas mileage in a typical vehicle? Of course you always hear the argument that manufacturers "have the technology" to make 40 mpg SUV's, and there's some kind of Big Oil consiracy preventing higher gas mileage engines from being developed. Regardless of whether this is BS or not (is it?), the fact that gas mileage in the typical pickup hasn't changed much in many years makes me wonder what's going on. Is there some sort of basic lack of material or combustion research that is preventing further progress? I know in jet engines, efficiency continues to increase as higher temperature materials become available. Higher combustor temps lead to more complete fuel combustion, better efficiencies, and less emissions. With automobiles comes economy of scale. If your basic half ton pickup could increase it's average gas mileage 50%, from 15 to 22.5 mpg over the course of a few years, can you imagine the overall savings? Even a 20% increase would be huge. You'd think manufacturers would be pursuing this... obviously they're not. They keep making 15 mpg trucks, and we keep buying them.