Fuel economy and trucks do not go hand-in-hand. When trucks are conceptualized, factors relating to utility such as cargo space, towing capacity and payload occupies the better part of the designer's mind than the overall efficiency of the vehicle.

On the other hand, automobile manufacturers who are trying to incorporate high mileage in to their vehicles often have to forego some of the essential capabilities that are of paramount importance to SUV and truck buyers- Downgrading capabilities such as smaller cargo or passenger capacity, lighter structures and smaller engines. This approach is counter-intuitive. This in no way is to suggest that one should deprive themselves from owning a van, SUV or a pickup truck just for the reason that they are not fuel efficient.

One must drive a vehicle that is best suited to the needs or sense of functionality and style. If an individual is interested in all of the above and also wants maximum efficiency, however, then the goal of that person ought to be to choose the model of truck that meets the overall requirement while at the same time have lowest emission and greatest fuel economy.

Governments across the globe aim at reducing vehicle-related evaporative and tailpipe emissions. With that noble aim as their guiding principle, they embark on a regulatory trip in order to increase the vehicle fuel economy of any auto manufacturer's entire product portfolio.
Not only this, the government even doles out huge amounts of subsidy to the manufacturers of automobiles that run on alternative fuels. The sole intent is to encourage the production and acceptance of such vehicles. Automakers are not upbeat with regards to such meddling by regulatory authorities who brandish draconian laws to threaten manufacturers in to submission. Hence, the automakers fine-tune their design in order to improve the average fuel-economy of their entire range just to meet the requirements of the authorities.

Precisely because of this reason, one will find quite a few SUVs and trucks known as FFV (flexible-fuel-vehicle) that have been designed in a manner to run on a mix of Ethanol and gasoline. Such vehicles are obviously sold at a price which is a tad higher than a standard price of a petrol-only model.
Trucks or SUVs that run on alternative fuels such as Ethanol emit lower levels of pollutants thus in effect bringing down emissions. This also helps in encouraging energy diversity. It must however be noted that ethanol contains energy which is not at par with gasoline. Therefore, a vehicle that is running on alternative fuel will give fewer miles per liter, than while it is running on gasoline. Although industry pundits are of the view that hybrid-electric drive train has more potential to bring down emission and be accepted by the masses as well.