ALL-WHEEL DRIVE OPERATION

The Audi Quattro has all-wheel drive. Thanks to the automatic locking center differential, engine power is distributed to suit the driving style and road conditions to the maximum extent. This is why the Quattro performs equally well on paved roads and motorways in normal conditions as well as in extreme conditions such as snow and ice, including off-road. At the same time, it is not an off-road vehicle, since its ground clearance is too low for that.

The drive system diagram is shown in the figure: 1 — front axle differential 2 — rear axle differential 3 — center differential 4 — driveshaft.

Operating principle: Engine power is transmitted through the transmission and the center differential directly to the front axle differential, and from it through the driveshaft to the rear axle differential.

The center differential, thanks to a complex worm gear mechanism, automatically locks the drive on slippery road surfaces without driver intervention.

During normal driving on dry road surfaces, it distributes engine power evenly to all wheels of the front and rear axles. If the wheels of one axle, for example on icy roads, lose stable grip with the road and approach the point of slipping, the center differential, without interrupting traction, automatically begins to lock these wheels, redistributing engine power to the wheels of the other axle, where grip with the road is more stable.

As you can see, the distribution of drive power to the wheels is not always even; it depends on road conditions, primarily on the degree of grip of the front or rear wheels with the road surface.

The rear axle differential lock can be engaged and disengaged manually. This lock is intended primarily for smooth starting and acceleration in difficult road conditions, and it disengages automatically when speed reaches approximately 25 km/h. The ABS anti-lock braking system is disabled during this time.