2005 PORSCHE CAYENNE S engine

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Shifting Gear, Traction Systems Off-road ABS
(ABS in Low Range program)
When Low Range is active, an ABS specially
matched to off-road driving is activated automati-
cally.
At speeds below 30 mph (50 km/h), the front
wheels can lock up in cycles during braking to
shorten the braking distance when the vehicle is
driven off-road (the wheels dig in to the surface).
If the driver needs to steer, this off-road driving
program is automatically switched off briefly to
maintain steerability.
HillholderIn selector lever positions D and M, the hillholder
function makes it easier to move off from a stand-
still on an upward slope when the engine is
running. The driver does not have to apply the
brake.
The hillholder thus makes moving off on slopes
easier.
Warning!
Risk of accident.
The vehicle can roll backwards if the Hillhold-
er is switched off.
fAlways apply the footbrake on slopes.
Hillholder is not active:
– In selector lever positions N and R
– In the reduced driving program and
– If not all of the wheels are touching the ground
(on difficult terrain, for example).
fPlease observe the chapter “STOPPING” on
Page 209.
Safety notes!
In spite of the advantages of the hillholder func-
tion, it is still the driver’s responsibility to adapt his
driving style and maneuvers in line with situational
conditions.
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 the hillholder function.
Driving at the limits should be avoided, e.g., on icy
slopes or on slippery surfaces. In this and similar
cases, the support of the hillholder function is not
ensured.

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225
Porsche Drive-Off Assistant –
Moving-off assistant on vehicles with
manual transmissionThe Porsche Drive-Off Assistant enables the driver
to move off on upward slopes. The vehicle must
have sufficient road contact to use this feature.
The Porsche Drive-Off Assistant is available for
slopes starting at approximately 5%.
fPlease observe the chapter “TRAILER
COUPLING” on Page 194.
Danger!
Risk of accident.
When moving off on a slippery surface (e.g.,
on icy or loose surfaces), assistance by the
Porsche Drive-Off Assistant is no longer
assured. In this case, the vehicle could slip.
The limits set by the physics of driving cannot
be overcome, even with the Porsche Drive-
Off Assistant. The responsibility for moving
off on upward slopes is still the driver's,
despite the Porsche Drive-Off Assistant.
fAlways adjust your driving style to the driving
conditions and vehicle load, use the footbrake if necessary.Moving off with Porsche Drive-Off Assistant
1. Hold the vehicle securely with footbrake or
parking brake on the slope.
The engine must be running.
2. Fully depress the clutch pedal.
3. Engage one of the gears used to ascend in the
direction of travel (1st gear or reverse).
4. While keeping the clutch pedal depressed,
release the footbrake or foot-operated parking
brake.
The vehicle is held on the slope.
5. Move off as usual.Note on operation
The Porsche Drive-Off Assistant ceases to
function:
– by shifting to neutral.
– when changing gears.
– by stopping or “stalling” the engine.
Danger!
Risk of accident.
If the Porsche Drive-Off Assistant ceases to
function, the vehicle will no longer be held on
a slope.
fHold the vehicle with the footbrake.

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Shifting Gear, Traction Systems
Engine Braking Support
(Assistance when heading downhill)The Porsche Down-Hill Assistant is an assistance
system which helps the driver at slower downhill
driving up to approx. 12 mph (20 km/h), e.g., on
steep slopes or on wintry mountain roads.
As long as the gas pedal is not used when trav-
eling downhill, the Porsche Down-Hill Assistant is
active and brakes the vehicle.
The braking ability of the Engine Braking Support
is affected by slippery surfaces (e.g., on icy or
loose surfaces), like all brakes.
If road grip is lost on one or more wheels, the
system brakes the wheels which have good road
contact.
Conditions:
– The gas pedal must not be used when
travelling downhill.
– The speed must not exceed 12 mph
(20 km/h).
– The selector lever position D or Mmust be
engaged.
Warning!
Risk of accident. Reduced braking ability on
a slippery surface.
fAlways adjust your driving style to the driving situation.
Tip on driving
The Porsche Down-Hill Assistant is active when
driving downhill either forwards or backwards.
Checks on test standsPower measurement
Power measurements on roller test stands are not
approved by Porsche.
Brake tests
Brake tests must be carried out only in High Range
and on plate-type test stands or roller test stands.
The following limit values must not be exceeded
on roller test stands:
– Testing speed 4.7 mph (7.5 km/h)
– Test duration 20 seconds
Parking brake test
Parking brake tests on the brake tester must be
performed only with the ignition switched off and
the selector lever in position N.
Balancing wheels on the vehicle
During finish balancing of the wheels, the entire ve-
hicle must be lifted and the wheels must be free to
turn.

Shifting Gear, Traction Systems
227
Off-Road DrivingPlease read this chapter carefully before driving
off road with your Porsche.
The information provided will familiarise you with
the special advantages of your vehicle, allowing
you to arrive at your destination safely every time.
We recommend practicing on less rugged terrain.
Vehicles with SportDesign package
Warning!
Risk of damage. On vehicles with Sport-
Design package, front, rear, and side
member trim are painted and pulled down
lower. Off-road driving can seriously damage
these trim parts.
fWhen driving off-road, make sure these parts
are not damaged.
fMake sure there is sufficient clearance
between obstacles and the underside of the
vehicle.
fAvoid driving through water.
fDo not use side member trim as a running board.Maintenance note
Please bear in mind that off-road driving subjects
all vehicle components to considerably more wear
than normal use, making professional inspection
and maintenance after each use a vital precondi-
tion for functioning and safety.
Grains of sand, dirt particles and other abrasive
materials entering the brakes can cause exces-
sive wear or unpredictable braking action.
Rules for off-road drivingfEnsure vehicle is equipped with approved all-
terrain tires.
fPlease observe the chapter “GROUND CLEA-
RANCE” on Page 366.
fActivate Low Range.
fStow or fasten luggage and loads securely.
Please observe the chapter “LOADING INFOR-
MATION” on Page 195.
fIf unknown terrain is obscured from view, ex-
amine it on foot first and traverse it with ex-
treme caution.
This way, obstacles are easier to recognise
and damage to the vehicle is avoided.
fAlways drive with the engine running.
Steering assistance is provided only with the
engine running.
fDrive slowly and uniformly.fAlways make sure that the wheels touch the
ground.
fBefore driving through water, check the water
depth, the condition of the surface beneath it
and the speed of the water.
fLook out for obstacles such as boulders,
holes, tree stumps or ruts.
fAlways keep the sliding/lifting roof or
Panorama roof system and the side windows
closed while driving.
fDo not depart from marked routes or paths.
fRespect Nature.
Always obey off-limits signs.

230
Shifting Gear, Traction Systems
Uphill driving
Danger!
Danger of serious personal injury or death
and risk of damage if the vehicle should
overturn.
fDo not turn around when driving uphill.
fIf it is not possible to climb a gradient, the car
must be backed down in reverse gear.
fDo not drive over embankments or slopes at
an angle to the line of maximum gradient.
fIf the vehicle starts to tilt, immediately steer in
the direction of the tilt (line of slope).
fWhen driving uphill, never let the vehicle roll
backward when in idle or not in gear.
Exclusive use of the footbrake is too risky in such situations.Note on operation
fActivate Low Range before taking extreme up-
ward or downward gradients.
Tips on driving
fDo not perform manual gear changes when
driving, and try to avoid stopping.
fAvoid high engine speeds (max. 2,500 rpm).
Traction on uphill slopesNote on operation
fActivate Low Range and engage differential
locks if necessary.
Tips on driving
fWhen driving uphill, go easy on the accelerator
and make sure that wheels have sufficient trac-
tion (don't spin).
fAvoid high engine speeds (max. 2,500 rpm).
fDrive slowly.

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231
Driving downhill
Danger!
There is a danger of serious personal injury
or death and risk of damage if the vehicle
should overturn.
fDo not drive over slopes at an angle to the line
of maximum gradient.
fDrive downhill slowly, with the wheels pointing
straight ahead.
fIf the vehicle starts to tilt, immediately steer in
the direction of the tilt (line of slope).
fWhen driving downhill, never let the vehicle roll
when in idle.
fUse engine braking effect.
If the engine braking effect is not adequate, gently apply the foot brake.Note on operation
fActivate Low Range. The off-road ABS is
switched on automatically.
Tips on driving
The same general principle as for uphill driving ap-
plies to downhill driving.
fDo not perform manual gear changes when
driving, and try to avoid stopping.
fAvoid high engine speeds (max. 2,500 rpm).
A special circuit of the off-road ABS permits con-
trolled brief lock-up of the front wheels so that they
can dig into the loose surface more effectively.
Locked wheels slip and can no longer be steered.
fWhen driving down steep hills on unpaved sur-
faces, brake carefully and do not start to slide.

232
Shifting Gear, Traction Systems
Water crossingfPlease observe the chapter “GROUND CLEA-
RANCE” on Page 366.
Danger!
Danger of drowning if water enters the vehi-
cle. Risk of damage to the engine and acces-
sories if water penetrates.
fBefore driving through water, check the water
depthA, water speed and the condition of the
surface beneath it.
The water must not be deeper than 20 in./
50 cm (22 in./55.5 cm for vehicles with level
control and height adjustment).
fCheck the door sills and rubber seals before
starting to drive.
fDo not drive through deep or rapidly flowing
water.
Deep or rapidly flowing water, e.g. mountain
streams, can cause the car to deviate from the
desired path.
fAvoid a "bow wave" by driving at an appropriate
speed.
fNever open the doors when driving through wa-
ter.Soiling can impair the braking action.
fCheck and clean the brakes if they have been
soiled.
Danger of steering assistance failing during
a long journey in the water if the drive belt
slips.
fIf the steering assistance fails, more effort will
be required to steer.
Danger of damaging electrical systems
fAvoid driving through salt water.
Notes on operation
fActivate Low Range.
fSwitch the air conditioner off.
fSwitch the headlights off.

Shifting Gear, Traction Systems
233
Tips on driving
fAvoid high engine speeds (max. 2,500 rpm).
fDo not perform manual gear changes when
driving, and try to avoid stopping.
Moving off in the water can be difficult due to
the high resistance and the loose surface in-
volved.
fStart the water crossing at a shallow place at
walking speed.
fAfter checking the body of water, take the
shortest path through it.
fNever drive into the water at high speed. The
resulting “bow wave” could damage the engine
and its accessories.
fAdjust your driving style to the unfamiliar sur-
roundings.
fCross the body of water slowly and at a con-
stant speed.
fNever turn around when crossing a body of wa-
ter.
fIf it is not possible to cross the body of water,
the car must be backed out of it in reverse
gear.
The servo pump and alternator can fail if the car is
driven through water for an extended period.
fIf the servo pump fails, substantially more
force will have to be exerted in order to steer. Maintenance note
The car requires a special check after the water
crossing.
fRemove mud from the tire tread.
fBriefly brake the brakes dry after driving
through the water.
HumpsfPlease observe the chapter “GROUND CLEA-
RANCE” on Page 366.
Note on operation
fActivate Low Range and engage differential
locks if necessary.
Tips on driving
fJust before reaching the hump, ease off the ac-
celerator slightly and use the car's momentum
to cross the hump. This will prevent the car
from jumping over the hump and landing on the
following downward slope at an excessive
speed.
fAvoid high engine speeds (max. 2,500 rpm).