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A sport utility vehicle (SUV) or off-roader is a vehicle that combines the load-hauling and passenger-carrying capacity of a large station wagon or minivan with features designed for off-road driving. In more recent years, the term has also grown to encompass vehicles with similar size and style that are marketed as sport utility vehicles, but which do not actually incorporate substantial off-road features. A new category, the crossover SUV uses car components for lighter weight and better economy.
SUVs have the general shape of a station wagon, but have a taller setup due to the more upright seating stance and a suspension designed for giving ground clearance for off-road driving. Typically, all four wheels can be driven, unlike most conventional cars in which only the front or rear wheels receive drive. The design also allows for a large engine compartment, and many SUVs have large V-6 or V-8 engines. In countries where fuel is more expensive, buyers often opt for diesel engines, which are more fuel efficient (and diesel fuel itself is often much cheaper).
Outside of North America these vehicles are known simply as four-wheel-drives, often abbreviated to 4WD or 4x4 (in the United States, many SUVs do not actually have four-wheel drive). In Australia, "Utility", or "Ute", refers an automobile with a flatbed rear or pick-up, typically seating two passengers and is often used by tradesmen, and is typically not a 4WD vehicle.
Descended from commercial and military vehicles such as the Jeep and Land Rover, they have been popular for many years with rural buyers due to their off-road abilities. However, in the last 25 years, and even more in the last decade, they have become popular with urban buyers. Consequently, more modern SUVs often come laden with luxury features and some crossover SUVs, such as the BMW X5, the Acura MDX, and the Toyota RAV-4, have adopted lower ride heights and more car-like suspension settings to better reflect their typical use (overwhelmingly, for normal on-road driving).
Some private SUV owners do indeed take their vehicles off the road to explore places otherwise unreachable by vehicle or for the sheer enjoyment of the driving. In Australia, China, Europe and the U.S. at least, many 4WD clubs have been formed for this purpose.
Modified SUVs also take part in races, most famously in the Paris-Dakar Rally, and the Australian Safari.
SUVs have become popular in US for a variety of reasons. Owners point to their large, comfortable cabins (which have nearly the passenger and equipment-carrying capabilities of minivans), perceived safety, and the recreational possibilities of the vehicles. Additionally, most large SUVs have far greater towing capacities than conventional cars, and in the case of trailerable boats have superior abilities to launch and retrieve those boats from slippery boat ramps (and, indeed, from many places where no made ramp exists).
Undoubtedly, though, some of their success is due to their rugged, powerful image, a substantial factor for many people who might more logically choose a more economical and cheaper minivan or station wagon. Vehicle manufacturers have been able to sell the image of SUVs effectively, with per-vehicle profits substantially higher than other automobiles. The simple design and often outdated technology (by passenger car standards) often makes the vehicles much cheaper to make than comparably-priced passenger vehicles.
The explosive growth in SUV ownership has attracted a large amount of criticism, mainly of the risks to other road users and the environment, but also on the basis that the perceived benefits to the vehicle owner are illusory or exaggerated.
Many of the largest and most expensive SUVs qualify as tax deductions in America, the amount of which can top $35,000. The tax code allows large (over 6,000 lbs BMW X5 (by 8 lbs!), Cadillac Escalade, GMC Yukon, Hummer H2, Land Rover Range Rover, Lexus LX, Lincoln Navigator, Mercedes-Benz M-Class, Toyota Land Cruiser, and Volkswagen Touareg.
Safety is one common point of criticism. Conventional automobiles are constructed by a method called unit-body construction, whereby a steel skeleton absorbs the impacts of collisions in crumple zones. Many SUVs, on the other hand, are constructed much more crudely: just rectangular steel frames which provide a comparatively low level of safety. However, some SUVs have designs based on conventional automobiles; the Lexus RX 330 (Motor Trend), RX 400h, and Acura MDX are three examples. As a result, these SUVs may avoid these safety issues.
The high center of gravity of SUVs makes them more prone to rollover accidents (especially in emergency manoeuvres) than lower vehicles. Consumer Reports has found a few SUVs unacceptable in recent years due to their rollover risk.
SUV safety concerns are compounded by a perception among some consumers that SUVs are more safe for their drivers than standard autos; this perception is generally incorrect, although SUVs might provide more safety in a few situations. According to G. C. Rapaille, a psychological consultant to automakers (as cited in Gladwell, 2004), many consumers feel safer in SUVs simply because their ride height makes "[their passengers] higher and dominate and look down [sic]. That you can look down is psychologically a very powerful notion". This and the massive size and weight of SUVs may lead to consumers' false perception of safety (Gladwell, 2004).
In 2004, the National Highway Traffic Safety Administration released figures showing that drivers of SUVs were 11 percent more likely to die in an accident than people in cars. These figures may be confounded by variables other than the vehicles' inherent safety, for example the documented tendency for SUVs to be driven more recklessly (most sensationally perhaps, the 1996 finding that SUV drivers are more likely to drive drunk ). SUV drivers are also statistically less likely to wear their seatbelts. The tendency to drive SUVs recklessly may be linked back to the perception that they provide superior driver protection.
Since the collision of an SUV with a pedestrian tends to impact the chest, while the collision of a car with a pedestrian tends to impact the knees, an SUV is about twice as likely to kill a pedestrian as a car at equal speed .
Also the size and design of SUVs leads to a restricted driver's view of the area immediately surrounding the vehicle. This means that young children are particularly vulnerable to collisions with SUVs as their size makes it more likely that they will not be seen by the driver. One study by the Chevrolet Suburban and the Ford Excursion) makes collisions with other, smaller cars much less dangerous for the SUV and much more dangerous for the car. The higher ride and other design characteristics of many SUVs may also lead to greater damage to smaller crash partner cars. These mass and design dangers are known as crash incompatibility issues in the crash testing industry, and are a topic of active research. The most notable statistic in SUV design crash incompatibility is an increase in fatalities when an SUV strikes the head of a passenger or driver in a side-impact collision. This is one of the chief motivations for the development of side-curtain airbags in standard autos.
Many motorists in the United States have expressed dismay at the proliferation of SUVs on the highways, contending that the tall, wide vehicles block less-elevated drivers' view of the road ahead. Additionally, the height of SUV headlights has been cause for complaint by drivers who find themselves dazzled at night by oncoming SUVs even when their lights are on low-beam settings.
The recent popularity of SUVs is one reason the U.S. population consumes more gasoline than in previous years. SUVs are as a class much less fuel efficient than comparable passenger vehicles. The main reason is that SUVs are classified by the U.S. government as light trucks, and thus are subject to the less strict light truck standard under the Corporate Average Fuel Economy (CAFE) regulations. The CAFE requirement for light trucks is an average of 20.7 mpg (US), versus 27.5 mpg (US) for passenger cars.
As there is little incentive to change the design, SUVs have numerous fuel-inefficient features. The high profile of SUVs increases wind resistance. The heavy suspension and large engines increases vehicle weight. SUVs also often come with tires designed for off-road traction rather than low rolling resistance. The more car-like SUVs tend to have a somewhat lower profile and better road performance tires, but often still have large, fuel-inefficient engines.
Manufacturers are attempting to improve the SUV to address these criticisms. The most recent generation of SUVs have been designed to reduce the rollover risk, and the smaller SUV models are essentially car drivetrains with taller wheels and bodywork, and are not much worse than their car counterparts in terms of fuel economy. As of 2004 no hybrid SUV is available to consumers, but a number are planned, of which the 2005 Ford Escape Hybrid is the only one with a definite production schedule. Like hybrid cars, this small SUV will show dramatically improved fuel economy over its conventionally-powered counterparts. Other manufacturers, including Lexus, plan small SUVs with hybrid power plants. Even though the gap between SUV safety and car safety has been growing, this is because car safety has been increasing faster than SUV safety; SUVs have become somewhat safer in recent years.
The Pew Forum on Religion and Public Life reports that, when polled, 29 percent of Americans say that Jesus would drive an SUV, while 33 percent say that he would not.
(Complete information on the Motor Trend reference is unavailable. However, the article was Motor Trend's announcement of the Lexus RX 300 as the 1999 SUV of the Year.)
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