Quattro

Quattro is the name Audi uses for its all-wheel-drive systems, first introduced on the 1980 Audi Quattro coupe. Unlike many part-time AWD systems of the era that were built for off-road trucks, the original Quattro system was designed to send power to all four wheels permanently in a road-going performance car, using a center differential to split torque between the front and rear axles at all times.

Audi brought the Quattro system into Group B rallying in the early 1980s, where the traction advantage of permanent all-wheel drive over rear-wheel-drive competitors proved decisive on loose and slippery surfaces. The Audi Quattro's rally success is widely credited with pushing all-wheel drive from a niche off-road feature into a mainstream layout for performance and rally-bred road cars, influencing competitors across the industry.

Modern Quattro systems have evolved into several variants depending on the platform, ranging from a mechanical center differential setup on longitudinal-engine models to an electronically controlled multi-plate clutch system on transverse-engine models. Across these variants, the shared goal is distributing torque between the axles, and in more advanced versions between individual wheels, to improve traction and handling in varying road conditions.