Gas-guzzler

Gas-guzzler commonly refers to a vehicle that is perceived to consume a lot of fuel.

The term originally came into use in the US when congress established Gas Guzzler Tax provisions in the Energy Tax Act of 1978 to discourage the production and purchase of fuel-inefficient vehicles. The gas guzzler tax had applied only to cars (not trucks) and was collected by the IRS. Other countries have followed suit and introduced their own version of a gas-guzzler tax such as Canada's "green levy".

There are several reasons for bad fuel economy in cars, vans and trucks:

Then there is the reduction of vehicle weight, with a switch to monocoque construction instead of body on frame construction and an increased use of lightweight materials, aluminium, plastics and high strength HSLA steels instead of ordinary mild carbon steel.

Gas-guzzlers are not only seeing a scale back in engine size and weight but also in the type of fuel used to power it to prevent environmental damage caused by the use of fossil fuels. The problem with these alternative fuel technologies is that they are either too expensive for widespread use and/or they are scarcely available especially in smaller countries.

Diesel technology is widespread in light trucks, especially in Japan and Europe. The bad reputation of diesel fuel and the previously bad quality of the fuel, however, have led to the rarity of such vehicles in the U.S market. The excessive particle emissions of diesel engines have also been cut back with particulate filters, which are offered for most modern diesel engines.

Fuel-efficient driving habits and vehicle maintenance are easy to change and can have a big impact on fuel consumption. Sudden acceleration and braking, traveling at high speeds, poorly maintained vehicles (frequency of oil changes and brand), and gasoline brands can also impact overall fuel consumption by over 25%. There are many other way to reduce your fuel consumption.

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Wikipedia