All-wheel drive (abbreviated AWD), sometimes called full-time four-wheel drive, is similar to four-wheel drive in that it provides power to all four wheels. The difference being that it has three differentials, one on each axle and a third between the two axles. This allows it to provide anywhere from 0%-100% of the total power to any wheel. While AWD is considered by most to be the optimal way for a motor vehicle to maintain traction on pavement, it is not as good off pavement and can be a problem during off-road driving when one wheel is in a slippery spot and absorbs all available power. This can be avoided by the use of limited slip differentials. Most AWD systems lack a low-range gear which makes them less capable in challenging off-road. All-wheel drive can be used on dry pavement, unlike part-time 4WD which locks the drive line front to rear and doesn't allow for variations in drive line speed using a differential.
Disadvantages and Overcoming Them
Every vehicle has its own unique challenges, whether it lacks certain abilities, is more demanding of its operator, or has limits of capacity, all vehicles are imperfect. The following entries address overcoming these obstacles.
- Unavailable Torque can be a problem for AWD systems. The simplest way to overcome this obstacle is to modify the vehicle's differentials with either limited slip or locking models.