Specifications

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quattro® with sports differential
With quattro®, we have created one of
the best all-wheel drive systems in the world.
Of course, that was not good enough for us.
quattro® is a permanent all-wheel drive system.
If the wheels on one axle of the vehicle lose grip
on the road and threaten to spin, then the power
is transferred to the other axle – automatically
and permanently distributed through the centre
differential. The basic distribution is 40:60 –
40% of the power comes from the front axle,
60% to the rear. The benefit is better traction
during acceleration and greater safety due to
the improved grip. So much for the technology.
But what makes quattro unique is really the
driving feel. “As if you were stuck to the road,”
some customers say. We put it like this: quattro
gives you more feel for the road – combined with
added safety.
quattro® with sports differential further reinforc-
es this unmistakeable quattro feeling. Vehicles
tend to experience understeer when steering or
driving into corners. This is a normal physical pro-
cess: a moving object opposes a change in direc-
tion. The elastic tyres and suspension mounts
tense up until the new direction has been adopt-
ed. When accelerating into a corner, the load on
the front axle is reduced and it therefore trans-
fers less lateral force to the tyres – the vehicle
understeers. With the sports differential on the
rear axle, the tendency to understeer is counter-
acted.
This is because the quattro rear axle differential
has been extended left and right by a clutch
system with two gear levels. These ensure that
the individual wheels on the rear axle receive
different levels of drive torque. The clutches
are activated by an electrohydraulic actuator.
Depending, for example, on the steering angle,
lateral acceleration, yaw angle and driving speed,
the system calculates the right distribution of
wheel torque for any driving situation. In this way
the power is specifically channelled to the outer
rear wheel, when steering or accelerating into a
corner.
The fuel consumption and CO₂ emission figures can be found on page 54.
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