Four on the Floor: All-Wheel-Drive Systems Explained

–

Torque, despite its industrious reputation, is lazy. Left undirected, like toddlers or teen­agers, it will frustrate, always preferring the path of least resistance. And in automotive terms, that most frequently means spinning tires. Not that we mind spinning tires, but since an engine’s job is to get us where we want to go, harnessing its torque to accomplish that task is only pragmatic. READ MORE ››

–
from Car and Driver Blog http://www.caranddriver.com/features/we-dissect-every-type-of-all-wheel-drive-system-feature