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Front-wheel drive (FWD) is a form of engine and transmission layout used in motor vehicles, where the engine drives the front wheels only. Most modern front-wheel-drive vehicles feature a transverse engine, rather than the conventional longitudinal engine arrangement generally found in rear-wheel-drive and four-wheel drive vehicles.

Front-wheel drive layout had been highly impacted by the success of small, inexpensive cars, especially the British Mini. As engineered by Alec Issigonis, the compact arrangement located the transmission and engine sharing a single oil sump — despite disparate lubricating requirements — and had the engine's radiator mounted to the side of the engine, away from the flow of fresh air and drawing heated rather than cool air over the engine. The layout often required the engine be removed to service the clutch.[14]

As engineer

As engineered by Dante Giacosa, the Fiat 128 featured a transverse-mounted engine with unequal length drive shafts and an innovative clutch release mechanism — an arrangement which Fiat had strategically tested on a previous production model, the Primula, from its less market-critical subsidiary, Autobianchi.

Ready for production in 1964, the Primula featured a gear train offset from the differential and final drive with unequal length drive shafts. The layout enabled the engine and gearbox to be located side by side without sharing lubricating fluid while orienting the cooling fan toward fresh air flow. By using the Primula as a test-bed, Fiat was able to sufficiently resolve the layout's disadvantages, including uneven side-to-side power transmission, uneven tire wear and potential torque steer, the tendency for the power of the engine alone to steer the car under heavy acceleration.

After the 128, Fiat further demonstrated the layout's flexibility, re-configurating the 128 drive-train as a mid-engined layout for the Fiat X1/9. The compact, efficient Giacosa layout — a transversely-mounted engine with transmission mounted beside the engine driving the front wheels through an offset final-drive and unequal-length driveshafts, combined with MacPherson struts and an independently located radiator — subsequently became common with competitors[15] and arguably an industry standard.[16]

The Corporate Average Fuel Economy standard drove a mass changeover of cars in the U.S. to front-wheel drive. The change began in 1978, with the introduction of the first American-built transverse-engined cars, the Plymouth Horizon and Dodge Omni (based on the European designed Simca Horizon),[17] followed by the 1980 Chevrolet Citation and numerous other vehicles. Meanwhile, European car makers, that had moved to front-wheel drive decades before, began to homogenize their engine arrangement only in this decade, leaving Audi (and Volkswagen) alone with the Audi front drive-longitudinal engine layout. Years before this was the most common layout in Europe, with examples like Citroen DS, Renault 12, Renault 5, Renault 25 (a Chrysler LH ancestor) Alfa Romeo 33, Volkswagen Passat, etc. This transition can be exemplified in the Renault 21 that was offered with disparate engine configurations. The 1.7-litre version featured an 'east-west' (transversely) mounted engine, but Renault had no gearbox suitable for a more powerful transverse engine: accordingly, faster versions featured longitudinally mounted (north south) engines.

By reducing drivetrain weight and space needs, vehicles could be made smaller and more efficient without sacrificing acceleration. Integrating the powertrain with a transverse as opposed to a longitudinal layout, along with unibody construction and the use of constant velocity jointed drive axles, along with front wheel drive has evolved into the mo

By reducing drivetrain weight and space needs, vehicles could be made smaller and more efficient without sacrificing acceleration. Integrating the powertrain with a transverse as opposed to a longitudinal layout, along with unibody construction and the use of constant velocity jointed drive axles, along with front wheel drive has evolved into the modern-day mass market automobile. Some suggest that the introduction of the modern Volkswagen Golf in 1974, from a traditional U.S. competitor, and the introduction of the 1973 Honda Civic, and the 1976 Honda Accord served as a wake-up call for the "Big Three" (only Chrysler already produced front-wheel-drive vehicles in their operations outside North America). GM was even later with the 1979 Vauxhall Astra/Opel Kadett. Captive imports were the US car makers initial response to the increased demand for economy cars. The popularity of front-wheel drive began to gain momentum, with the 1981 Ford Escort, the 1982 Nissan Sentra, and the 1983 Toyota Corolla. Front-wheel drive became the norm for mid-sized cars starting with the 1982 Chevrolet Celebrity, 1982 Toyota Camry, 1983 Dodge 600, 1985 Nissan Maxima, 1986 Honda Legend, and the 1986 Ford Taurus. By the mid-1980s, most formerly rear-wheel-drive Japanese models were front-wheel drive, and by the mid-1990s, most American brands only sold a handful of rear-wheel-drive models.

The vast majority of front-wheel-drive vehicles today use a transversely mounted engine with "end-on" mounted transmission, driving the front wheels via driveshafts linked via constant velocity (CV) joints, and a flexibly located electronically controlled cooling fan.[1] This configuration was pioneered by Dante Giacosa in the 1964 Autobianchi Primula and popularized with the Fiat 128.[18] Fiat promoted in its advertising that mechanical features consumed only 20% of the vehicle's volume and that Enzo Ferrari drove a 128 as his personal vehicle.[15] The 1959 Mini used a substantially different arrangement with the transmission in the sump, and the cooling fan drawing hot air from its side-facing location.

Volvo Cars has switched its entire lineup after the 900 series to front-wheel drive. Swedish engineers at the company have said that transversely mounted engines allow for more crumple zone area in a head-on collision. American auto manufacturers are now shifting larger models (such as the Chrysler 300 and most of the Cadillac lineup) back to rear-wheel drive.[19][20] There were relatively few rear-wheel-drive cars marketed in North America by the early 1990s; Chrysler's car line-up was entirely front-wheel drive by 1990. GM followed suit in 1996 where its B-body line was phased out, where its sports cars (Camaro, Firebird, Corvette) were the only RWDs marketed; by the early 2000s, the Chevrolet Corvette and Volvo Cars has switched its entire lineup after the 900 series to front-wheel drive. Swedish engineers at the company have said that transversely mounted engines allow for more crumple zone area in a head-on collision. American auto manufacturers are now shifting larger models (such as the Chrysler 300 and most of the Cadillac lineup) back to rear-wheel drive.[19][20] There were relatively few rear-wheel-drive cars marketed in North America by the early 1990s; Chrysler's car line-up was entirely front-wheel drive by 1990. GM followed suit in 1996 where its B-body line was phased out, where its sports cars (Camaro, Firebird, Corvette) were the only RWDs marketed; by the early 2000s, the Chevrolet Corvette and Cadillac Catera were the only RWD cars offered by General Motors until the introduction of the Sigma platform. After the phaseout of the Ford Panther platform (except for the Mustang), Ford automobiles (including the Transit Connect van) manufactured for the 2012 model year to present are front wheel drive; its D3 platform (based on a Volvo platform) has optional all wheel drive.