Porsche Cayenne User Handbook Manual page 49

Intelligent, discreet, responsive.
The ideal travelling companion.
Porsche Traction Management (PTM)
on the Cayenne, Cayenne S,
Cayenne GTS and Cayenne Turbo.
Porsche Traction Management (PTM) is
an active all-wheel drive system with an
electronically variable, map-controlled
multi-plate clutch, automatic brake differ-
ential (ABD) and anti-slip regulation (ASR).
Torque is distributed between the front
and rear axles by means of the electron-
ically variable multi-plate clutch. For the
toughest off-road terrain, the differential
can be locked using the PTM control on
the centre console. With the aid of on-
board sensors, the status of the car is
continuously monitored and the front/
rear split is adjusted to match changing
driving conditions. The sensors are used
to measure a range of values, including
the rotational speed of all four wheels,
the lateral and longitudinal acceleration
of the car, and the current steering
angle.
If, for example, the rear wheels threaten
to lose traction under acceleration, a
greater proportion of drive torque is
automatically transmitted to the front
axle by a more positive engagement of
the multi-plate clutch. In addition, ASR
minimises wheel spin. During cornering,
the required level of engine torque is
distributed to the front wheels to ensure
excellent lateral stability.
In conjunction with advanced Porsche
Stability Management (PSM, p. 70), PTM
ensures the perfect distribution of drive
torque for optimum traction in all road
All-wheel drive on the Cayenne, Cayenne S, Cayenne GTS and Cayenne Turbo
scenarios, whether on long straights,
through tight corners or on surfaces
with different friction coefficients. If one
of the wheels is about to lose traction,
PTM uses the ABD function to apply the
corresponding brake. As a result, more
drive is automatically transferred to
the opposite wheel. If both wheels on
one axle are in danger of slipping, ASR
immediately intervenes and modifies
engine output to maintain drive. As well
as enhancing traction and active safety,
Porsche Traction Management (PTM)
offers exceptional handling and driving
dynamics.
Standard on the Cayenne, Cayenne S,
Cayenne GTS and Cayenne Turbo.
Drive systems and chassis | Transmission · 49