Despite its name, all-wheel-drive (AWD) is very seldom all four wheels driving the car equally.
In many cases, especially on lower-priced AWD vehicles, torque – the engine’s power – is distributed between the front and rear axles.
A more sophisticated system can also further distribute it between individual wheels, as it does with Nissan’s torque vectoring system. It’s found on the all-new Juke crossover, where the company says it’s the only car in its segment with such a feature.
“Not only does it split torque up to 50/50 between the front and rear wheels for additional traction, it can also split side-to-side across the rear axle, up to 50 percent on either side,” says Rui Nunes, manager, chief marketing manager for Nissan Canada. “This results in improved vehicle stability, cornering and overall performance.”
Front-wheel-drive vehicles power the front wheels only; the engine and transmission are not connected to the rear wheels, which are “pulled along” by the front ones. In an AWD vehicle, a shaft runs lengthwise under the car to the rear wheels to send power to them. The AWD Juke initially powers its front wheels only, until the driver hits a switch to engage the all-wheel system. From there, the vehicle’s sensors constantly monitor it, determining if a rear wheel needs to be powered.
“The front wheels are always equally powered, left to right,” Nunes says. “The rear can shift depending on environmental conditions, such as rain, snow, mud or gravel.
If you’re cornering, it could send, say, 42 percent to one rear wheel and 8 percent to the other, because the one that needs more traction gets sent more torque.
If you didn’t have the torque vectoring, it would only be able to split the torque between the front and rear, not from side to side as well.”
The new Nissan system is also considerably lighter than most other AWD systems, which improves fuel efficiency and vehicle handling when compared to heavier ones.