Information on Front Wheel Drive

Function

A car that uses front-wheel drive gets its driving force, as well as all traction for steering, from the two front wheels. The rear wheels simply spin to keep the rear end of the vehicle stable. A front-wheel drive configuration has the engine and transmission connected to the front differential and the wheels via spindles rather than a single axle. This is because, in addition to powering the car, the front wheels need to pivot to provide steering.

Front-wheel drive cars began to appear in the American market in the 1980s. What started as a trend from European automakers eventually encompasses the majority of models made by the major U.S. automakers, as well as Asian imports. Throughout the 1990s, rear-wheel drive was reserved for very few models, including some trucks, sports cars and large luxury vehicles. However, since the early 2000s, automakers have been increasing the number of rear-wheel drive offerings.

There are several advantages to a front-wheel drive configuration. Since there is no need to provide mechanical linkage between the front engine compartment and the rear axle (via a trans-axle), front-wheel drive systems save money and reduce weight.

At the same time, front-wheel drive cars have the engine located directly above the drive wheels, putting the engine's weight to work in forcing the wheels downward toward the road surface and thus providing better traction. Front-wheel drive cars also use a transverse engine mount, with the length of the engine running perpendicular to the vehicle. This removes the need for long hoods to contain large engines and frees up more space for interior room, as in the classic "cab-forward" design.

Front-wheel drive also has its share of drawbacks. One major disadvantage is the phenomenon known as torque steer. This occurs because the front wheels have a limited amount of traction, which must be shared between forward momentum to drive the car with lateral force to steer it. The result is poor handling performance compared to rear-wheel drive cars, where the front wheels are used only for steering.

Another shortcoming of the front-wheel drive system is the uneven balance of cars that have all of their weight, including the engine and drive components, toward the front of the car. Rear-wheel drive vehicles require additional drive components near the rear wheels, which distributed the vehicle's weight more evenly.

One reason that automakers were so keen to adopt front-wheel drive cars had to do with vehicle safety. Since rear-wheel drive vehicles with front engines have less weight over the drive wheels, slipping was common on slick roads. Drivers try to combat this by placing cinder blocks or other heavy objects in the trunks of rear-wheel drive cars.

Modern safety systems like anti-lock brakes and electronic stability control make the safety issues associated with rear-wheel drive cars largely obsolete. Removing this advantage once held by front-wheel drive was a large part of the resurgence of new rear-wheel drive cars.