According to an article in the New York Times on February 8, Americans, having found a foul-weather friend in their four-wheel-drive sport utilities, are gaining new choices in vehicles with enhanced winter traction.Beyond truck-based utilities, and apart from the more carlike SUV pretenders known as crossovers, dozens of conventional passenger cars are now driven by all four wheels — and more models are on the way.While a few all-wheel-drive cars are well established, especially those from Audi and Subaru, the new wave extends to mainstream family sedans like the new Chrysler 300 and Ford Five Hundred, and even to inexpensive subcompacts like the Suzuki Aerio.Detroit, which has concentrated on four-wheel-drive trucks, is playing catch-up. In 2002, 9.9 percent of foreign-brand cars sold in the United States had all-wheel drive, according to J. D. Power & Associates, compared with only 1.4 percent for the Big Three. The firm expects 42 more all-wheel-drive cars in the next five years. An advantage of all-wheel drive is better traction on slick roads, as the systems direct power from slipping wheels to those with traction — formulas and methods vary.Sophisticated electronics, often linked to existing antilock-brake and traction-control systems, have made conversions to all-wheel drive relatively simple and inexpensive. In the past, heavy mechanical systems stole space and added considerable weight. All-wheel drive is generally defined as a system that remains continuously engaged, requiring no action from the driver. In contrast, four-wheel drive often requires the driver to push a button or pull a lever to switch out of two-wheel drive, and the systems in many trucks include a low gear range for extreme off-road conditions.Among European automakers, Mercedes-Benz offers all-wheel drive on its three main lines of sedans and wagons. BMW makes it available on the 3 Series, and Volkswagen has extended the option to four-cylinder Passats. Volvo is putting an all-wheel-drive option on its small S40 sedan and V50 wagon, in addition to its S60 sedan, V70 wagon and S80 luxury car. Infiniti now offers an all-wheel-drive version of its G35 sport sedan. Lexus will add the feature to its 2006 GS line, due next year. GM will continue to sell minivans with an all-wheel-drive option through 2004. But in September, the company will begin offering what it calls "crossover sport vans," which will use many of the same components but will look more like SUVs — and will be available with all-wheel drive.