220
Shifting Gear, Traction Systems
Manual transmission, clutch
Warning!
Risk of accident.
fDo not obstruct the pedal travel with floor mats or other objects.
Floor mats of the correct size and with the
appropriate fasteners are available from your
authorized Porsche dealer.The positions of the gears are shown on the shift
diagram on the gearshift lever.
fWhen shifting gears, always ensure that the
clutch pedal is fully depressed and the gear
has fully engaged.
fSelect reverse only when vehicle is stationary.
fSelect an appropriately low gear on upward
and downward slopes.
This will ensure optimum use of engine power
and engine braking.
When reverse gear is selected and the ignition is
on, the reversing lights are lit.
Permitted engine speedfYou should change into a higher gear before
the needle reaches the red mark on the
tachometer, or ease off the accelerator.
If the red zone is reached during acceleration, fuel
feed is interrupted.
Caution!
Risk of engine damage (overrevving) when
shifting down to a lower gear.
fTake care not to exceed the maximum permit-ted engine speed when down-shifting.
Shifting Gear, Traction Systems
225
M - Manual selection mode (in the on-
road driving program)The functions of selector lever positions D and M
differ in the on-road program, High Range, and in
the off-road program, Low Range.
The currently selected gear is retained if you
change from D to M.
If you change from M to D, the gear-changing map
suitable for your current driving style is selected
and the appropriate gear is selected.
Warning!
The kickdown function is not active in manual
selection mode “M“.
The kickdown function cannot be used to
downshift in manual selection mode “M“.
fTherefore shift down manually when accelerat-ing (e.g. to overtake).
Shifting up
fPress upper part (+) of a rocker switch A or
fPush selector lever B forward in the M gate.Shifting down
fPress lower part (–) of a rocker switch A or
fPush selector lever B back in the M gate.
Depending on driving speed and engine speed,
you can shift up or down at any time. Gear chang-
es which would exceed the upper or lower engine-
speed limit are not executed by the control unit.
You can change down two gears by quickly press-
ing rocker switches A or selector lever B twice.
If PSM is active and the engine-speed limit is
reached, an automatic upward shift is performed
or, just before idling speed is reached, a down-
ward shift is performed.
fSelect an appropriately low gear on upward
and downward slopes.
This will ensure optimum use of engine power
and engine braking.
If manual mode fails, the control electronics
switch to automatic mode.
In this event, the instrument panel will display se-
lector lever position D.
fTo remedy the fault, please consult an author-
ized Porsche dealer.
f f f
226
Shifting Gear, Traction Systems
M - Manual selection mode (in the off-
road driving program)The functions of selector lever positions D and M
differ in the on-road program, High Range, and in
the off-road program, Low Range.
The currently selected gear is retained if you
change from D to M.
If you change from M to D, the gear-changing map
suitable for your current driving style is selected
and the appropriate gear is selected.
Warning!
The kickdown function is not active in manual
selection mode “M“.
The kickdown function cannot be used to
downshift in manual selection mode “M“.
fTherefore shift down manually when accelerat-ing (e.g. to overtake).
Tip on driving
The kickdown function is not active in selector le-
ver position M.
Unlike in the road driving program, an automatic
upshift is not performed when the engine-speed
limit is reached.
Shifting up
fPress upper part (+) of a rocker switch A or
fPush selector lever B forward in the M gate.Shifting down
fPress lower part (–) of a rocker switch A or
fPush selector lever B back in the M gate.
Depending on driving speed and engine speed,
you can shift up or down at any time. Gear chang-
es which would exceed the upper or lower engine-
speed limit are not executed by the control unit.
You can change down two gears by quickly press-
ing rocker switches A or selector lever B twice.
The gear is changed down automatically just be-
fore idle speed is reached.
fSelect an appropriately low gear on upward
and downward slopes.
This will ensure optimum use of engine power
and engine braking.
If manual mode fails, the control electronics
switch to automatic mode. In this event, the instru-
ment panel will display selector lever position D.
fTo remedy the fault, please consult an author-
ized Porsche dealer.
Shifting Gear, Traction Systems
227
StoppingfFor a brief stop (e.g. at a traffic light), leave the
selector lever in drive position and hold the ve-
hicle with the brake pedal.
fDo not hold the car on a slope using the accel-
erator. Use the brake pedal or the parking
brake instead.
fBefore leaving the vehicle, always apply the
handbrake and move the selector lever to
position P.
Tip on driving
In selector lever positions D and M, the Hillholder
prevents the car from rolling backward when it has
been stopped on an upward slope with the engine
running.
fPlease observe the chapter “HILLHOLDER” on
Page 242.
ParkingfGo easy on the accelerator.
fWhen parking or maneuvring in a small space,
control the speed by careful use of the foot-
brake.Driving in winterIn wintry road conditions it is advisable to take
steep inclines in manual mode M. This prevents
the occurrence of gear changes that could cause
wheelspin.
Reduced driving programIf there is a fault in the transmission:
–An X appears instead of the current gear
indicator on the multi-purpose display of the in-
strument panel.
The transmission no longer shifts.
fTo remedy the fault, immediately consult an au-
thorized Porsche dealer.
Warning!
Reverse gear lock monitoring is disabled in
the emergency running program.
Damage to the vehicle may result as well as
loss of control, if the vehicle is moving for-
ward fast enough to cause rear wheel lockup.
fDo not shift into R while the vehicle is moving forward.
Tip on driving
3rd or 5th gear in selector position D and reverse
gear R are now available and will allow you to
reach the nearest authorized Porsche dealer.
fPlease go to your authorized Porsche dealer
as soon as possible.
Shifting Gear, Traction Systems
233
Disengaging
fPress button E.
Disengagement of the anti-roll bars is indicated
on the multi-purpose display of the instrument
panel and by illumination of light-emitting diode
F.
The light-emitting diode on the button flashes
several times during the disengagement
process.
The anti-roll bars are disengaged.
Note on operation
The anti-roll bars cannot be disengaged manually
at speeds above 25 mph (40 km/h).
Engaging
fPress button E.
Light-emitting diode F on the button flashes
several times during the engagement
process and then goes out.
The anti-roll bars are engaged.Note on operation
The anti-roll bars are engaged automatically when
a speed of 30 mph (50 km/h) is exceeded or
when the lateral acceleration value is high.
Notes
Engagement of the anti-roll bars is audible.
At temperatures below –4°F (–20°C), the anti-roll
bars take somewhat longer to engage.Indication of a fault by:
– Continuous illumination of the light-emitting
diode in the button
– Illumination of the warning light on the
instrument panel
– A message on the multi-purpose display of the
instrument panel
fAdapt your driving behavior to the changed
conditions.
Drive slowly to the nearest authorized Porsche
dealer and have the fault remedied.
fPlease observe the chapter “WARNING LIGHTS
AND WARNING MESSAGES” on Page 124.
Indicator light and warnings
236
Shifting Gear, Traction Systems
Porsche Traction Management (PTM)Porsche Traction Management is a full-time all-
wheel control system designed to influence the
longitudinal and lateral dynamics. It is closely
linked with the Porsche Stability Management
(PSM) system:
PTM ensures the best possible power distribution
to the four driven wheels at the front and rear ax-
les. The system realises this optimal traction by in-
tervening in the lock control function of the trans-
fer case and rear differential. PTM is active at all
times and, unlike the PSM, cannot be switched off.Advantages of PTM
– Obvious improvement in traction, driving stabil-
ity and steering ability of the car.
– Vehicle is more manageable when driven at its
performance limits.
– Improved straight-ahead tracking and stability.
– The aforementioned features allow for a sport-
ier setup of the running gear.
– The TCS and ABD provide even better traction
for all wheels.
Warning!
In spite of the advantages of PTM, it is still the driv-
er’s responsibility to adapt his/her driving style
and maneuvres in line with road and weather con-
ditions, as well as the traffic situation.
The increased safety that is provided should not in-
duce you to take greater risks with your safety.
The limits set by the physics of driving cannot be
overcome, even with PTM.
Risks of accident due to inappropriate speed
cannot be reduced by PTM.
Shifting Gear, Traction Systems
237
Full-time all-wheel drive
With the four-wheel drive, the drive power is varia-
bly distributed to the front and rear wheels.
Power distribution and wheel speed compensation
between the front and rear axles is realised with a
transfer box.
Distribution of the drive power depends on the
wheel speed difference between the two axles.
The transfer box always controls power distribu-
tion in such a way that optimal propulsion is
achieved, even on an unfavorable road surface.
Full-time four-wheel drive ensures optimal handling
and great stability.
Warning!
In spite of the advantages of four-wheel drive, it is
still the driver’s responsibility to adapt his driving
style and maneuvers in line with road and weather
conditions, as well as the traffic situation.
The increased safety that is provided should not in-
duce you to take greater risks with your safety.
The limits set by the physics of driving cannot be
overcome, even with four-wheel drive.
Risks of accident due to inappropriate speed can-
not be reduced by four-wheel drive.Automatic brake differential (ABD)
The ABD system controls the front and rear axles
separately. If one wheel of an axle starts to spin,
it is braked so that the other wheel on the same
axle can be driven.
The ABD recognises different driving states, and it
features control strategies adapted to these
states. In situations in which little propulsive power
is required, such as when the car moves off on a
level gravel surface, traction control already be-
comes active at low engine speeds. If great
propulsive power is required, e.g. when moving off
on an uphill slope or for rapid acceleration, the
ABD is adapted accordingly.
A special off-road program is used in Low Range
mode.Traction control system (TCS)
The traction control system prevents the wheels
from spinning by adjusting the engine power,
thereby ensuring good lane-holding ability and a
stable driving behavior.
238
Shifting Gear, Traction Systems
Porsche Stability Management (PSM)PSM is an active control system for stabilisation of
the vehicle during extreme driving maneuvres. It
operates together with the Porsche Traction
Management (PTM) system.
PSM makes use of both the ABD and TCS sys-
tems, as well as the known functions of the anti-
lock brake system (ABS) and engine drag torque
control system (MSR).
Warning!
In spite of the advantages of PSM, it is still the driv-
er’s responsibility to adapt his driving style and
maneuvres in line with road and weather condi-
tions, as well as the traffic situation.
The increased safety that is provided should not in-
duce you to take greater risks with your safety.
The limits set by the physics of driving cannot be
overcome, even with PSM.
Risks of accident due to inappropriate speed
cannot be reduced by PSM.Advantages of PSM
– Best possible traction and lane-holding ability
in all driving situations – even on road surfaces
with varying friction.
– The system compensates for undesired vehi-
cle reactions (load-alteration effect) when the
driver releases the accelerator pedal or brakes
on corners. This compensation functions up to
the maximum lateral acceleration.
– PSM actively stabilises the vehicle in the event
of under and oversteering during dynamic
driving maneuvres (e.g. rapid steering move-
ments, during lane changes or on alternating
corners).
– Improved braking stability on corners and on
different or varying road surfaces.Readiness for operation
PSM is switched on automatically every time you
start the engine.
Function
Sensors at the wheels, brakes, steering system
and engine continuously measure:
–Driving speed
– Direction of travel
– Lateral acceleration
– Longitudinal acceleration
– Rate of turn about the vertical axis
PSM uses these values to determine the direction
of travel desired by the driver.
PSM intervenes and corrects the course if the ac-
tual direction of motion deviates from the desired
course (steering-wheel position):
It brakes individual wheels as needed. If neces-
sary, PSM additionally influences the engine power
or the gear-changing characteristic of the Tiptron-
ic in order to stabilise the vehicle.