A V6 engine is a V engine with six cylinders mounted on the crankshaft in two banks of three cylinders set at a 60 or 90 degree angle to each other. The V6 is one of the most compact engine configurations ranging from 2.0 L to 4.3 L displacement, it is shorter than the inline 4. Because of its short length, the V6 fits well in the used transverse engine front-wheel drive layout; the V6 is commercially successful in contemporary mid-size cars because it is less expensive to build and is smoother in large sizes than the inline 4, which develops serious vibration problems in larger engines. The wider 90° V6 will fit in an engine compartment designed for a V8, providing a low-cost alternative to the V8 in an expensive car, while the narrower 60° V6 will fit in most engine compartments designed for an I4, proving a more powerful and smoother alternative engine to the four. Buyers of luxury and/or performance cars might prefer an inline 6, which has better smoothness, or a flat 6 which has a lower center of gravity.
Recent forced induction V6 engines have delivered horsepower and torque output comparable to contemporary larger displacement aspirated V8 engines, while reducing fuel consumption and emissions, such as the Volkswagen Group's 3.0 TFSI, supercharged and directly injected, Ford Motor Company's turbocharged and directly injected EcoBoost V6, both of which have been compared to Volkswagen's 4.2 V8 engine. Modern V6 engines range in displacement from 2.0 to 4.3 L, though larger and smaller examples have been produced, such as the 1991 Mazda MX3, the Rover KV6 engine. Some of the first V6-powered automobiles were built in 1905 by Marmon; this firm became something of a V-engine specialist producing, in the 1930s, a V16 engine, as one of the few automakers in the world. From 1908 to 1913, the Deutz Gasmotoren Fabrik produced gasoline-electric train sets which used a V6 as generator engine. In 1918 Leo Goosen designed a V6-powered car for Buick Chief Engineer Walter L. Marr. Only one prototype Buick V6 car was built in 1918.
The first series-production V6 was introduced by Lancia in 1950 with the Lancia Aurelia model. Lancia sought a more powerful engine that would fit into an existing narrow engine bay. Lancia engineer Francesco De Virgilio began analyzing the vibration of alternative V-angles for a V6 engine in 1943, he found that a V6 with its cylinders positioned at a 60° V-angle could be made uniquely smooth-running in comparison with other possible V-angles. There was resistance to his conclusion because the V6 was a unknown engine type in the 1950s, his design featured four main bearings and six crankpins, resulting in evenly spaced firing intervals and low vibrations. Other manufacturers took note and soon other V6 engines were designed. In 1959, General Motors' GMC Truck division introduced a new 60-degree heavy-duty 305 in3 gasoline-fueled 60° V6 for use in their pickup trucks and Suburbans; the use of the sweet spot of 60 degrees' V-angle maximized power while minimizing vibration and exterior dimensions of the engine.
In short, GMC introduced a compact V6 design at a time when the straight-six engine was considered the pinnacle of 6-cylinder design.1962 saw the introduction of the Buick Special, which offered a new 90° V6 with uneven firing intervals, derived from—and shared some parts with—a small Buick V8 engine of the period. To save design time and expense, it was built much like a V8; the combination of a 90° V-angle with only three crank pins—set at 120° apart, with opposing cylinders sharing a crank pin as most V8 engines do—the cylinders fired alternatively at 90 and 150° of crankshaft rotation. This uneven firing caused harmonic vibrations in the drive train that were perceived as a rough-running engine by the buyers. GM sold the engine tooling to Kaiser-Jeep in 1967. In 1977, Buick introduced a split pin crankshaft to implement an even-fire version of this engine in which cylinders fired every 120°; the V6 does not have the inherent freedom from vibration that the inline-six and flat-six have, but it can be modeled as two separate straight-3 engines sharing a crankshaft.
Counterweights on the crankshaft and a counter-rotating balance shaft are required to compensate for the first order rocking motions. Straight engines with an odd number of cylinders are inherently unbalanced because there is always an odd number of pistons moving in one direction while a different number move the opposite direction; this causes an end-to-end rocking motion at crankshaft speed in a straight-three engine. V6 designs will behave like two unbalanced three-cylinder engines running on the same crankshaft unless steps are taken to mitigate it, for instance by using offset journals or flying arms on the crankshaft or a counter-rotating balance shaft. In the V6 with 120° between banks, pairs of connecting rods can share a single crank pin, but the two cylinder banks run like two inline 3s, both having an end-to-end rocking couple. Unlike in a V8 engine with a crossplane crankshaft, the vibrations from one bank do not cancel the vibrations from the other, so a rotating balancing shaft is required to compensate for the primary vibrations.
Because the 120° V6 is nearly as wide as a 180° flat-6 but is not nearly as smooth, can be more expensive if a balancing shaft is added, this configuration is seen in production engines. In the V6 with 90° between cylinders, split crank pins are required to offset the connecting rods by 30° to achieve an 120° between firing intervals, crankshaft counterw
Taiga known as boreal forest or snow forest, is a biome characterized by coniferous forests consisting of pines and larches. The taiga is the world's largest land biome. In North America, it covers most of inland Canada and parts of the northern contiguous United States. In Eurasia, it covers most of Sweden, much of Norway, some of the Scottish Highlands, some lowland/coastal areas of Iceland, much of Russia from Karelia in the west to the Pacific Ocean, areas of northern Kazakhstan, northern Mongolia, northern Japan. However, the main tree species, the length of the growing season and summer temperatures vary. For example, the taiga of North America consists of spruces. A different use of the term taiga is encountered in the English language, with "boreal forest" used in the United States and Canada to refer to only the more southerly part of the biome, while "taiga" is used to describe the more barren areas of the northernmost part of the biome approaching the tree line and the tundra biome.
Hoffman discusses the origin of this differential use in North America and why it is an inappropriate differentiation of the Russian term. Although at high elevations taiga grades into alpine tundra through Krummholz, it is not an alpine biome. Taiga is the world's second-largest land biome, after deserts and xeric shrublands, covering 17 million square kilometers or 11.5% of the Earth's land area. The largest areas are located in Canada; the taiga is the terrestrial biome with the lowest annual average temperatures after the tundra and permanent ice caps. Extreme winter minimums in the northern taiga are lower than those of the tundra; the lowest reliably recorded temperatures in the Northern Hemisphere were recorded in the taiga of northeastern Russia. The taiga or boreal forest has a subarctic climate with large temperature range between seasons, but the long and cold winter is the dominant feature; this climate is classified as Dfc, Dsc and Dwd in the Köppen climate classification scheme, meaning that the short summer lasts 1–3 months and always less than 4 months.
In Siberian taiga the average temperature of the coldest month is between −6 °C and −50 °C. There are some much smaller areas grading towards the oceanic Cfc climate with milder winters, whilst the extreme south and west of the taiga reaches into humid continental climates with longer summers; the mean annual temperature varies from −5 °C to 5 °C, but there are taiga areas in eastern Siberia and interior Alaska-Yukon where the mean annual reaches down to −10 °C. According to some sources, the boreal forest grades into a temperate mixed forest when mean annual temperature reaches about 3 °C. Discontinuous permafrost is found in areas with mean annual temperature below 0 °C, whilst in the Dfd and Dwd climate zones continuous permafrost occurs and restricts growth to shallow-rooted trees like Siberian larch; the winters, with average temperatures below freezing, last five to seven months. Temperatures vary from −54 °C to 30 °C throughout the whole year; the summers, while short, are warm and humid.
In much of the taiga, −20 °C would be a typical winter day temperature and 18 °C an average summer day. The growing season, when the vegetation in the taiga comes alive, is slightly longer than the climatic definition of summer as the plants of the boreal biome have a lower threshold to trigger growth. In Canada and Finland, the growing season is estimated by using the period of the year when the 24-hour average temperature is +5 °C or more. For the Taiga Plains in Canada, growing season varies from 80 to 150 days, in the Taiga Shield from 100 to 140 days; some sources claim 130 days growing season as typical for the taiga. Other sources mention. Data for locations in southwest Yukon gives 80–120 frost-free days; the closed canopy boreal forest in Kenozersky National Park near Plesetsk, Arkhangelsk Province, Russia, on average has 108 frost-free days. The longest growing season is found in the smaller areas with oceanic influences; the shortest growing season is found at the northern taiga–tundra ecotone, where the northern taiga forest no longer can grow and the tundra dominates the landscape when the growing season is down to 50–70 days, the 24-hr average of the warmest month of the year is 10 °C or less.
High latitudes mean that the sun does not rise far above the horizon, less solar energy is received than further south. But the high latitude ensures long summer days, as the sun stays above the horizon nearly 20 hours each day, with only around 6 hours of daylight occurring in the dark winters, depending on latitude; the areas of the taiga inside the Arctic Circle have midnight sun in mid-summer and polar night in mid-winter. The taiga experiences low precipitation throughout the year as rain during the summer months, but as fog and snow; this fog predominant in low-lying areas during and after the thawing of frozen Arctic seas
The Audi Q7 is a full-size luxury SUV made by the German manufacturer Audi, unveiled in September 2005 at the Frankfurt Motor Show. Production of this 7-seater SUV began in the autumn of 2005 at the Volkswagen Bratislava Plant in Bratislava, Slovakia, it was the first SUV offering from Audi and went on sale in 2006. Audi's second SUV, the Q5, was unveiled as a 2009 model. Audi has since unveiled a third SUV model, the Q3, which went on sale in the 3rd quarter of 2011; the Q7 shares a Volkswagen Group MLB platform and chassis with the Bentley Bentayga, Lamborghini Urus, Porsche Cayenne and the Volkswagen Touareg The Q7 utilizes a modified version of the Volkswagen Group PL71 platform. Previewed by the Audi Pikes Peak quattro concept car, the Q7 is designed more for on-road use, was not meant for serious off-road use where a transfer case is needed. In an off-road test through the Australian outback it fared well for a "soft roader". Although it lacks a low-range transfer case, it has quattro permanent four-wheel drive system with a central locking differential, a self-levelling air suspension with Continuous Damping Control, called Adaptive air suspension, which helps in off-road situations.
Development began in 2002 under the code AU 716 focused on the Pikes Peak Concept. Design work was frozen for the Concept in July 2002, for presentation at the North American International Auto Show in January 2003. Following the introduction of the concept, full-scale development began on Typ 4L of the PL71 platform; the production design was frozen for a late 2005 start of production. Prototypes went into testing in 2004, with development concluding in the first half of 2005, it introduced. While the Q7 has been the flagship SUV in Audi's product portfolio, a new top-of-the-line model, to be called the Audi Q8, is in the cards, it debuted in its concept form at the 2017 Detroit auto show. Q7 offers an optional feature marketed as Audi Music Interface, to allow user manipulation of an iPod or similar MP3-style player, which can play through the Multi Media Interface. Q7 was the first Audi model to offer a type of blind-spot detection and warning system. Source 0–100 km/h performance for Q7 3.6 VR6 FSI is 8.5s, 4.2 V8 FSI is 7.4s and for 6.0 V12 TDI is 5.5s.
Despite its multiple airbags and safety electronics, such as Electronic Stability Programme, the Q7 scored only four stars out of five in the Euro NCAP crash test for adult occupant protection. According to Audi, this was caused by a design error, has since been fixed in cars manufactured after the test which should lead to five stars. Official tests to prove this remain to be done as of March 2009. However, in the United States, the Q7 received five out of five stars from the National Highway Traffic Safety Administration safety test for both front and side impacts; the Insurance Institute for Highway Safety awarded the Q7 its Top Safety Pick 2009, with Good ratings in all 14 measured categories of the front and side impact test. The 2015 Q7 has a rollover risk of 18.5%. It was first released with Q7 4.2 quattro available at launch. The Q7 hybrid is a concept vehicle using the engine from the 4.2 FSI with an electric motor to provide 200 N⋅m extra torque, nickel-metal hydride battery. It has 0–100 km/h acceleration time of 6.8 seconds.
The vehicle weighs 2,410 kg, 140 kg heavier than the petrol counterpart. The vehicle was unveiled at the 2005 Frankfurt Motor Show. Audi was going to introduce a hybrid version of the Q7 sometime in the future. However, the low US dollar caused Audi to drop the plans for the US market, but stated limited quantities would be available for the commercial market. Audi's research and development chief, Michael Dick announced Q7 hybrid would be produced in limited numbers for test purposes only and that development work would focus on a more advanced lithium-ion battery-based hybrid system for the Q5; the Q7 3.0 TDI clean diesel is a version of the 3.0 V6 TDI with selective catalytic reduction. The engine was used in the next generation of the Q7 for the European market; the 3.0-litre TDI S line has a top speed of 134 mph. US models of the 2009 Audi Q7 TDI Premium went on sale in 2009-04 with a base MSRP of $50,900; the vehicle was unveiled at the 2007 Geneva Motor Show. The production version went on sale in early summer 2007.
The V12 TDI engine was "based" on the diesel technology from Audi R10 TDI race car, though both engines are unrelated: the bore / stroke / angle of the blocks are different and they do not share a single component. The only twelve-cylinder diesel engine used in any passenger car, it was rated at 500 PS and 1,000 N⋅m of torque; this gives the vehicle a 0–100 km/h acceleration time of 5.5 seconds. The Q7 V12 TDI is, according to Audi, the best handling Q7 due to a revised suspension and brakes. Audi claims; the concept vehicle appeared at the 2006 Paris Motor Show. Audi had announced V12 diesel version for the US market using diesel emission treatment technology jointly developed with Volkswagen and Mercedes-Benz under the label "BlueTec". Audi cancelled the plan to federalize the Q7 V12 TDI for the US market due in part to the global financial crisis of 2008; this V12 version is no longer available for the model year 2013 in anticipation of the cosmetic and mechanical update of Q7 for 2014. The auto listing websites
The Porsche Cayenne is a mid-size luxury crossover sport utility vehicle produced by the German manufacturer Porsche since 2002, with North American sales beginning in 2003. It is the first V8-engined vehicle built by Porsche since 1995, when the Porsche 928 was discontinued, it is Porsche's first off road variant vehicle since its Super and Junior tractors of the 1950s, the first Porsche with four doors. Since 2008, all engines have featured direct injection technology; the second-generation Cayenne was unveiled at the 2010 Geneva Motor Show in March following an online reveal. The Cayenne shares its platform, body frame and electronics with the similar Volkswagen Touareg and Audi Q7; the second generation received a facelift in 2014 with minor external changes, introduced a new plug-in E-Hybrid version, with its public launch at the Paris Motor Show. The Porsche Cayenne entered the market with mixed anticipation. However, it soon proved that it was the performance vehicle among SUVs and was praised for its excellent handling and powerful engines.
The lineup consisted of the V8-powered Cayenne S and Cayenne Turbo. In the model cycle, VR6 and diesel-powered versions joined the lineup; the base model is powered by a 3.2-L VR6 engine producing 250 PS. Acceleration from 0–60 mph is approx 7.5 seconds with the manual transmission and 8.1 seconds with the Tiptronic S. The S is powered by an 8-cylinder engine with a dry-sump lubrication system and variable valve timing, it produces 340 310 lb ⋅ ft of torque. Acceleration from 0 -- 60 mph takes the top speed is 150 mph. Introduced only for 2006, a special distinctive Cayenne S Titanium Edition Wagon, a 1 Year exclusive, limited production SUV featuring a lightweight steel body, titanium-painted accented body parts, side lower rocker body panels, 4 sports chrome tailpipes, 19" titanium painted alloy wheels, bi-xenon headlights, two-tone interior upholstery, Porsche PCM w/ trip computer navigation, MP3 audio and Bose cabin surround sound; this sporty design S is powered by an alloy 4.5L V8 engine with a dry-sump lubrication system and variable valve timing.
The Cayenne S engine produces 340 310 lb · ft of torque. Acceleration is quicker from 0–60 mph at sub 6.8 seconds and the top speed is 150+ mph. It featured sport tuned suspension, includes a low-range case, a locking differential and six-speed automatic Tiptronic transmission; the GTS features a sport suspension and 21-inch wheels. It has an aerodynamic body kit; the Porsche Cayenne GTS has a 0–100 km/h time of 5.7 seconds. A six-speed manual transmission is offered; the first-generation Cayenne Turbo has 450 PS, can accelerate from 0–100 km/h in 5.3 seconds. A Turbo S version was built in 2006 to compete with the Mercedes-Benz ML 63 AMG; the Cayenne Turbo and Turbo S include a low-range case, a locking differential, height-adjustable, off-road suspension. The S is powered by a twin-turbocharged 4.5 L V8 that produces 720 N ⋅ m of torque. In 2008 an updated Turbo model, featuring a larger 4.8-L engine, was revealed at the Beijing Auto Show. It produces 50 PS more power, can accelerate from 0–60 mph in 4.9 seconds.
Revealed with the new Turbo, was a new 550 hp Turbo S model. Acceleration from 0–60 mph for that car takes 4.7 seconds and it can be had with optional ceramic composite brakes. Porsche has sold a diesel version of the Cayenne, powered by a 3.0-L V6 VW TDI engine, since February 2009. The engine is rated at 550 N ⋅ m of torque; the car was unveiled at the 2009 Geneva Motor Show. The diesel can accelerate from 0–60 mph in 9.2 seconds. The Cayenne S Transsyberia was a racing vehicle for Transsyberia rally, only 26 were built; the street version was built to commemorate Porsche's victory in Transsyberia rally. It is a variant with the 405 hp direct-inject 4.8-L V8 from the Cayenne GTS. Sales began with a production run of 600 road vehicles. In May 2009, a limited edition version based on the Cayenne GTS was introduced, designed by Porsche Design Studio and included a Porsche Design chronograph Type P’6612. Production was limited to 1000 units, 100 in the USA; the second-generation Porsche Cayenne went on sale in April–May 2010 as a 2011 model, with an official debut at the 2010 Geneva Motor Show.
In preparation for the unveiling, the Cayenne production facility in Leipzig, closed in December 2009 to commence factory retooling for the new model, a process that took 2–3 months. The 2011 Porsche Cayenne is larger than its predecessors, but features a more slanted rear window, less upright windshield, a more sloping roofline, door-mounted mirrors, smaller windows at the rear of the vehicle, headlights inspired by the Carrera GT, taillights that extend onto the car's tailgate, LED daytime running lights and a vastly redesigned interior modeled after the Panamera; the 2011 Cayenne is 250 kg lighter than the previous models due to extensive use of aluminum and magnesium, making it more fuel efficient than the previous lineup. Despite its lower stance, the new vehicle's off-road capabilities have been retained without compromising the street performance-orien
A portmanteau or portmanteau word is a linguistic blend of words, in which parts of multiple words or their phones are combined into a new word, as in smog, coined by blending smoke and fog, or motel, from motor and hotel. In linguistics, a portmanteau is defined as a single morph; the definition overlaps with the grammatical term contraction, but contractions are formed from words that would otherwise appear together in sequence, such as do and not to make don't, whereas a portmanteau word is formed by combining two or more existing words that all relate to a singular concept. A portmanteau differs from a compound, which does not involve the truncation of parts of the stems of the blended words. For instance, starfish is not a portmanteau, of star and fish; the word portmanteau was first used in this sense by Lewis Carroll in the book Through the Looking-Glass, in which Humpty Dumpty explains to Alice the coinage of the unusual words in "Jabberwocky", where slithy means "slimy and lithe" and mimsy is "miserable and flimsy".
Humpty Dumpty explains to Alice the practice of combining words in various ways: You see it's like a portmanteau—there are two meanings packed up into one word. In his introduction to The Hunting of the Snark, Carroll uses portmanteau when discussing lexical selection: Humpty Dumpty's theory, of two meanings packed into one word like a portmanteau, seems to me the right explanation for all. For instance, take the two words "fuming" and "furious." Make up your mind that you will say both words, but leave it unsettled which you will say first … if you have the rarest of gifts, a balanced mind, you will say "frumious." In then-contemporary English, a portmanteau was a suitcase. The etymology of the word is the French porte-manteau, from porter, "to carry", manteau, "cloak". In modern French, a porte-manteau is a clothes valet, a coat-tree or similar article of furniture for hanging up jackets, hats and the like. An occasional synonym for "portmanteau word" is frankenword, an autological word exemplifying the phenomenon it describes, blending "Frankenstein" and "word".
Many neologisms are examples of blends. In Punch in 1896, the word brunch was introduced as a "portmanteau word." In 1964, the newly independent African republic of Tanganyika and Zanzibar chose the portmanteau word Tanzania as its name. Eurasia is a portmanteau of Europe and Asia; some city names are portmanteaus of the border regions they straddle: Texarkana spreads across the Texas-Arkansas border, while Calexico and Mexicali are the American and Mexican sides of a single conurbation. A scientific example is a liger, a cross between a male lion and a female tiger. Many company or brand names are portmanteaus, including Microsoft, a portmanteau of microcomputer and software. "Jeoportmanteau!" is a recurring category on the American television quiz show Jeopardy!. The category's name is itself a portmanteau of the words "Jeopardy" and "portmanteau." Responses in the category are portmanteaus constructed by fitting two words together. Portmanteau words may be produced by joining together proper nouns with common nouns, such as "gerrymandering", which refers to the scheme of Massachusetts Governor Elbridge Gerry for politically contrived redistricting.
The term gerrymander has itself contributed to portmanteau terms playmander. Oxbridge is a common portmanteau for the UK's two oldest universities, those of Oxford and Cambridge. In 2016, Britain's planned exit from the European Union became known as "Brexit". David Beckham's English mansion Rowneybury House was nicknamed "Beckingham Palace", a portmanteau of his surname and Buckingham Palace. Many portmanteau words do not appear in all dictionaries. For example, a spork is an eating utensil, a combination of a spoon and a fork, a skort is an item of clothing, part skirt, part shorts. On the other hand, turducken, a dish made by inserting a chicken into a duck, the duck into a turkey, was added to the Oxford English Dictionary in 2010; the word refudiate was first used by Sarah Palin when she misspoke, conflating the words refute and repudiate. Though a gaffe, the word was recognized as the New Oxford American Dictionary's "Word of the Year" in 2010; the business lexicon is replete with newly coined portmanteau words like "permalance", "advertainment", "advertorial", "infotainment", "infomercial".
A company name may be portmanteau as well as a product name. Two proper names can be used in creating a portmanteau word in r
An all-wheel drive vehicle is one with a powertrain capable of providing power to all its wheels, whether full-time or on-demand. The most common forms of all-wheel drive are: 4×4 Reflecting two axles with both wheels on each capable of being powered. 6×6 Reflecting three axles with both wheels on each capable of being powered. 8×8 Reflecting four axles with both wheels on each capable of being powered. Vehicles may be either part-time all-wheel drive or full-time: On-demand One axle is permanently connected to the drive, the other is being connected as needed Full-time All axles are permanently connected, with or without a differential. Independent The wheels are not dependent on a transaxle. Tesla's vehicles are so far the only ones to use such a system. Today, the designation AWD is becoming narrowed in North America, to apply to vehicles with drive train systems that have permanent drive and include a differential between the front and rear drive shafts. However, the designations AWD and all-wheel drive long predated the trend, with Associated Equipment Company building AWD trucks in conjunction with FWD in 1929, General Motors manufacturing a line as "all-wheel drive" as early as the late 1930s.
This distinction in terminology is not used outside North America. When tire grip is good during road driving, a differential is used between the axles to avoid driveline windup; this is not required off-road. All-wheel drive vehicles designed for extensive off-road use may not have such a differential, so they suffer from wind-up when used on-road. Selectable 4WD avoids this problem and requires only a simple dog clutch in the transfer case, rather than a differential. For this reason, most early off-road vehicles used that system; as vehicles became more sophisticated and tires gave better winter performance in the 1960s there was an interest in giving the benefits of all-wheel drive to conventional cars. Exotic vehicles such as the high-powered Jensen FF followed by the AMC Eagle, Subaru Leone and Audi Quattro series were the first to offer all-wheel drive in a high-speed road-based car; these the Quattro, would extensively develop this drivetrain with the use of viscous couplings and differentials to provide a safe and drivable car.
The first off-road / on-road hybrids such as the Range Rover chose the permanent all wheel drive system rather than manual selection. Selectable 4WD has both axles rigidly coupled together, which has some advantages in poor off-road conditions. To gain the same advantage in a permanent AWD system with a differential, the differential can be locked manually with a differential lock; as this control is misunderstood and mis-used, which can cause damage due to wind-up, they have tended to be replaced by automatic locking through the viscous couplers. Front-wheel drive Rear-wheel drive All-terrain vehicle Two-wheel drive H-drive Four Wheel Drive or FWD, one of the first companies, from 1909, to build four-wheel drive vehicles
Sport utility vehicle
Sport-utility, SUV or sport-ute is an automotive classification a kind of station wagon / estate car with off-road vehicle features like raised ground clearance and ruggedness, available four-wheel drive. Many SUVs are built on a light-truck chassis but operated as a family vehicle, though designed to be used on rougher surfaces, most used on city streets or highways. In recent years, in some countries the term SUV has replaced terms like "Jeep" or "Land-Rover" in the popular lexicon as a generic description for light 4WD vehicles. Many SUVs have an upright built body and tall interior packaging, a high seating position and center of gravity, available all-wheel drive for off-road capability; some SUVs include the towing capacity of a pickup truck and the passenger-carrying space of a minivan or large sedan. The traditional truck-based SUV is more and more being supplanted by unitary body SUVs and crossovers based on regular automobile platforms for lighter weight and better fuel efficiency.
In some countries, notably the United States, SUVs are not classified as cars, but as light trucks. SUVs overtook lower medium segment cars to become the world's largest automotive segment in 2015, accounting for 22.9 percent of global light vehicle sales, or 36.8% of the world's passenger car market. Worldwide sales of SUVs grew from 5 million units in 2000 to 20 million in 2015 and are forecast to hit 42 million units by 2031. Becoming popular in the 1990s and early 2000s, SUVs combined with other light trucks, like pickups and minivans, supplanted many conventional large passenger cars and station wagons, changed the composition of America's vehicle fleet. SUV sales temporarily declined due to high oil prices and a declining economy, but by 2010, SUV sales around the world were growing again, in spite of gasoline prices; the market has overwhelmingly come to prefer 4/5-door models in favor of popular 2-door off-roaders. There is no universally accepted definition of the sport utility vehicle.
Dictionaries, automotive experts, journalists use varying wordings and defining characteristics, in addition to which there are regional variations of the use by both the media and the general public. The auto industry has not settled on one definition of the SUV either; the actual term "Sport Utility Vehicle" did not come into wide popular usage until the late 1980s — prior to such vehicles were marketed during their era as 4-wheel drives, station wagons, or other monikers. The American Merriam-Webster online dictionary offers three different definitions; the general definition of a "sport-utility vehicle", found under "SUV" reads: "a rugged automotive vehicle similar to a station wagon but built on a light-truck chassis", it is defined in the definition of sport-utility vehicle for students as: "an automobile similar to a station wagon but built on a light truck frame". However, the Merriam-Webster definition "for English Language Learners" reads: "a large vehicle, designed to be used on rough surfaces but, used on city roads or highways".
The Webster's New World Dictionary defines sport utility vehicle as "a passenger vehicle similar to a station wagon but with the chassis of a small truck and four-wheel drive". In recent years, the term SUV has come to replace the use of "jeep" as a generic trademark and description of these type of vehicles, a name that originated during World War II as slang for the light general purpose military truck. A Hemmings article defines the sport utility vehicle as bridging the gap between cars and trucks, "combining car-like appointments and wagon practicality with steadfast off-road capability". S. it only applies to the newer street oriented one, whereas "Jeep", "Land Rover" or 4x4 are used for the off-roader oriented ones. The German automaker BMW utilizes the term SAV to denote "Sport Activity Vehicles." Not all SUVs have four-wheel drive capabilities, not all four-wheel-drive passenger vehicles are SUVs. Although some SUVs have off-road capabilities, they play only a secondary role, SUVs do not have the ability to switch among two-wheel and four-wheel-drive high gearing and four-wheel-drive low gearing.
While automakers tout an SUV's off-road prowess with advertising and naming, the daily use of SUVs is on paved roads. In British English the terms "four-by-four" or "off-road vehicle" are preferred, for example the Chambers Dictionary has no entry for sport utility vehicle; the Collins English online dictionary defines sport utility vehicle as a "powerful vehicle with four-wheel drive that can be driven over rough ground" or "a high-powered car with four-wheel drive designed for off-road use", but the citations quoted by Collins are few. Other alternative terms are "four-wheel drive", or using the brand name to describe the vehicle. In the United States, many government regulations have categories for "off-highway vehicles" which are loosely defined and result in SUVs being classified as light trucks. For example, Corporate Average Fuel Economy regulations included "permit greater cargo-carrying capacity than passenger carrying volume" in the definition for trucks, resulting in SUVs being classified as light trucks.
This classification as trucks allowed SUVs to be regulated