quattro (four-wheel drive)

quattro (four-wheel drive)
Name	quattro (four-wheel drive)
Manufacturer	Audi AG
Production	1980s–present
Class	Automotive technology
Layout	Four-wheel drive layout

quattro (four-wheel drive) quattro is a proprietary all-wheel drive system developed by Audi AG that integrates drivetrain, chassis, and electronic control technologies for passenger cars and light trucks. It pioneered mass-market all-wheel drive use in European automobiles and influenced competitive strategies among BMW, Mercedes-Benz, Volkswagen Group, Subaru Corporation, and Nissan Motor Company. The name became a marketing and engineering hallmark linked to motorsport successes such as the World Rally Championship and endurance events like the 24 Hours of Le Mans.

Overview

The quattro name refers to an integrated drivetrain and control philosophy combining a powered engine output distribution to four wheels, centralized differentials, and electronic management by suppliers such as Bosch and ZF Friedrichshafen AG. Early applications appeared on models manufactured by Audi Sport GmbH and produced in factories in Ingolstadt and Neckarsulm. The system contributed to Audi's brand identity alongside models like the Audi Quattro (Urquattro), Audi A4, Audi A6, and Audi TT, and shaped marketing campaigns at events such as the Paris Motor Show and Geneva Motor Show.

History and Development

Development was driven by engineers within Audi AG and researchers at institutions collaborating with suppliers like Brembo and Magneti Marelli. Early demonstration vehicles emerged in the late 1970s before commercial debut in the early 1980s, coinciding with regulatory shifts in European Community markets and competition from Lancia and Toyota Motor Corporation. Motorsport applications under teams such as Audi Sport and drivers like Michele Mouton and Walter Röhrl showcased advantages in traction at rally stages used in the World Rally Championship, while endurance applications were tested at circuits such as Nürburgring and Silverstone Circuit. Legal and commercial considerations involved Volkswagen Group corporate strategy and licensing discussions with component makers.

Technology and Variants

quattro systems evolved into longitudinal-engine variants with overt mechanical center differentials and transverse-engine variants using Haldex-type multi-plate clutch assemblies sourced from suppliers like Haldex AB. Variants include permanent mechanical systems with planetary center differentials, torque-vectoring differentials developed with companies such as GKN, and electronically controlled clutch systems tuned using software from Continental AG and Robert Bosch GmbH. The system family spans models equipped with Torsen differentials, multi-plate clutch packs, and electronically actuated limited-slip differentials used in performance divisions and AMG competitors from Mercedes-AMG.

Mechanical Components and Operation

Key components include the differential units—front, rear, and center—along with driveshafts, propeller shafts, transfer cases, and electronically controlled multi-plate clutches. Mechanical suppliers include ZF Friedrichshafen AG, GKN plc, and BorgWarner; electronic control units are often developed with Bosch. Torque distribution strategies depend on sensor input from ABS modules and stability control systems developed by firms such as Magneti Marelli and tuned in collaboration with Audi Sport GmbH. In Torsen-equipped layouts the worm-gear based torque biasing acts as a mechanical torque-vectoring device, whereas Haldex-based layouts rely on hydraulic actuation commanded by ECU algorithms derived from research at institutions like the Technical University of Munich.

Performance and Applications

quattro-equipped vehicles deliver improved traction and handling in varied conditions such as wet tarmac, snow, gravel, and high-speed circuit driving observed at venues like Circuit de la Sarthe and rally stages in Monte Carlo Rally. Applications span luxury sedans, sport coupes, crossovers, and racing prototypes used by factory teams in series like the World Endurance Championship and hillclimb events such as the Pikes Peak International Hill Climb. Performance benefits are often benchmarked against rivals from BMW M GmbH, Mercedes-AMG, and Porsche AG in comparative tests conducted by publications like Autocar and Top Gear.

Comparison with Other Four-Wheel Drive Systems

Compared with part-time transfer case systems used historically by Land Rover and Jeep (Stellantis), quattro emphasizes permanent or actively managed torque distribution rather than driver-operated high/low gearing. Against systems by Subaru Corporation (symmetrical AWD) and BMW xDrive, quattro implementations emphasize packaging differences—longitudinal engine layouts with center differentials versus transverse-mounted engines with on-demand clutches—while companies such as GKN and BorgWarner supply comparable torque coupling hardware. Motorsport comparisons include Audi Sport's dominance in the Group B era contrasted with competitors like Lancia Stratos and manufacturer efforts by Ford Motor Company in the WRC.

Category:Automotive technology Category:Audi