torque SUBARU IMPREZA WRX STI 2011 Owners Manual

Black plate (141,1)
北米Model "A1110BE-C" EDITED: 2010/ 12/ 17
is not working properly. Contact your
nearest SUBARU dealer for service im-
mediately.&
Rear differential oil
temperature warning
light (STI)
CAUTION
Reduce vehicle speed and park the
vehicle in a safe place as soon as
possible if the R.DIFF TEMP light
illuminates. Continued driving with
this light illuminated can damage
the rear differential and other parts
of the powertrain.
If this light illuminates when the engine is
running, it may indicate that the rear
differential oil temperature is too hot.
At this time, the driver ’s control center
differential will automatically cancel the
current torque-distribution ratio setting and
adopt its minimum ratio.
If the light illuminates while driving, reduce
vehicle speed and stop the vehicle at the
nearest safe place. Park the vehicle for
several minutes. After the light turns off,
you can start driving.
If the light does not turn off, contact the
nearest SUBARU dealer for service.
NOTE. If the tire pressures are not correct
and/or the tires are not all the same
size and brand, the rear differential will
be heavily loaded when the vehicle is
driven, resulting in an abnormally high
oil temperature.
. The rear differential oil will deterio-
rate if its temperature increases en-
ough for the rear differential oil tem-
perature warning light to illuminate. It is
advisable to have the rear differential
oil replaced as soon as possible.&
Low tire pressure
warning light (U.S.-spec.
models)
When the ignition switch is turned to the
“ON ”position, the low tire pressure warn-
ing light will illuminate for approximately 2
seconds to check that the tire pressure
monitoring system (TPMS) is functioning
properly. If there is no problem and all tires
are properly inflated, the light will turn off.
Each tire, including the spare (if provided),
should be checked monthly when cold
and inflated to the inflation pressure
recommended by the vehicle manufac-
turer on the vehicle placard or tire inflation
pressure label. (If your vehicle has tires of
a different size than the size indicated on the vehicle placard or tire inflation pres-
sure label, you should determine the
proper tire inflation pressure for those
tires.)
As an added safety feature, your vehicle
has been equipped with a tire pressure
monitoring system (TPMS) that illuminates
a low tire pressure telltale when one or
more of your tires is significantly under-
inflated. Accordingly, when the low tire
pressure telltale illuminates, you should
stop and check your tires as soon as
possible, and inflate them to the proper
pressure. Driving on a significantly under-
inflated tire causes the tire to overheat and
can lead to tire failure. Under-inflation also
reduces fuel efficiency and tire tread life,
and may affect the vehicle
’s handling and
stopping ability.
Please note that the TPMS is not a
substitute for proper tire maintenance,
and it is the driver ’s responsibility to
maintain correct tire pressure, even if
under-inflation has not reached the level
to trigger illumination of the TPMS low tire
pressure telltale.
Your vehicle has also been equipped with
a TPMS malfunction indicator to indicate
when the system is not operating properly.
The TPMS malfunction indicator is com-
bined with the low tire pressure telltale.
When the system detects a malfunction,
Instruments and controls
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3

Black plate (149,1)
北米Model "A1110BE-C" EDITED: 2010/ 12/ 17
turn it again to the “ON ”position.
. If this indicator light and the CHECK
ENGINE warning light/malfunction in-
dicator lamp flash simultaneously dur-
ing driving, have the vehicle checked
by your nearest SUBARU dealer.&
Cruise control set in-
dicator light
This light illuminates when vehicle speed
has been set.&
Front fog light indicator
light (if equipped)
This indicator light illuminates while the
front fog lights are illuminated.&
Headlight indicator
light (if equipped)
This indicator light illuminates when the
headlight switch is placed in the “
”or
“
” position.
& Driver ’s control center differ-
ential auto indicator light
(STI)This light functions while the ignition
switch is “ON ”. When illuminated, it
indicates that the driver ’s control center
differential is set to the auto mode. It turns
off when the driver ’s control center differ-
ential is set to the manual mode. For
details, refer to “Driver’s Control Center
Differential (DCCD) (STI) ”F 7-18.
! Driver ’s control center dif-
ferential auto [+] indicator
lightWhen the AUTO [+] mode is set, the
AUTO [+] indicator light illuminates.
For details, refer to “Driver ’sControl
Center Differential (DCCD) (STI) ”F 7-18. !
Driver ’s control center dif-
ferential auto [ ] indicator
light
When the AUTO [ ] mode is set, the
AUTO [ ] indicator light illuminates.
For details, refer to “Driver ’s Control
Center Differential (DCCD) (STI) ”F 7-18.& Driver ’s control center differ-
ential indicator and warning
lights (STI)! Indicator lightsWhen you select the manual mode of the
driver ’s control center differential, the
initial limited slip differential (LSD) torque
that is currently selected for the center
differential is indicated by the illumination
of these indicator lights.
Instruments and controls
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3

Black plate (286,1)
北米Model "A1110BE-C" EDITED: 2010/ 12/ 17
7-18
Starting and operating
Non-turbo models
mph (km/h)
1st 32 (51)
2nd 53 (86)
3rd 76 (122)
Turbo models mph (km/h)
1st 35 (56)
2nd 58 (94)
3rd 85 (137)
WARNING
When shifting down a gear, ensure
that the vehicle is not travelling at a
speed exceeding the Maximum Al-
lowable Speed for the gear which is
about to be selected. Failure to
observe this precaution can lead to
engine over-revving and this in turn
can result in engine damage.
In addition, sudden application of
engine brakes when the vehicle is
travelling on a slippery surface can
lead to wheel locking; as a conse-
quence, control of the vehicle may
be lost and the risk of an accident
increased.
NOTENever exceed the posted speed limit.&
Driving tipsDo not drive with your foot resting on the
clutch pedal and do not use the clutch to
hold your vehicle at a standstill on an
upgrade. Either of those actions may
cause clutch damage.
Do not drive with your hand resting on the
shift lever. This may cause wear on the
transmission components.
When it is necessary to reduce vehicle
speed due to slow traffic, turning corners,
or driving up steep hills, downshift to a
lower gear before the engine starts to
labor.
On steep downgrades, downshift the
transmission to 4th, 3rd or 2nd gear as
necessary; this helps to maintain a safe
speed and to extend brake pad life.
In this way, the engine provides a braking
effect. Remember, if you “ride”(over use)
the brakes while descending a hill, they
may overheat and not work properly.
The engine may, on rare occasions, knock
when the vehicle rapidly accelerates or
rapidly pulls away from a standstill. This
phenomenon is not an indication of a
problem in your vehicle.
Driver ’s Control Center Dif-
ferential (DCCD) (STI)
WARNING
Always use the utmost care when
driving. Being overconfident be-
cause you are driving a vehicle with
a driver ’s control center differential
could easily lead to a serious acci-
dent.
CAUTION
All the indicator lights will flash in
the event that the driver ’s control
center differential has a malfunc-
tion. Have the vehicle inspected by
your SUBARU dealer.
The driver ’s control center differential
allows you to freely change the degree
of limitation of the d ifferential action
(limited slip differential (LSD) torque) of
your vehicle’ s center differential.
By using the center differential control
switch, you can set an initial LSD torque to
match the road surface conditions, driving
conditions and your driving style.

Black plate (287,1)
北米Model "A1110BE-C" EDITED: 2010/ 12/ 17
1) LSD torque
2) Traction torque
3) Initial LSD torque (maximum)
4) Initial LSD torque (minimum)
A) Initial LSD torque (adjustable)
B) Mechanical LSD torqueThe driver ’s control center differential has
an auto mode and a manual mode. In the
auto mode, the system automatically
adjusts the initial LSD torque. In the
manual mode, you can change to the
desired mode manually by using the
center differential control switch.NOTEIf you rapidly depress and release the
accelerator pedal while driving at low
speed, you may hear a knocking sound
from the vicinity of the center differen- tial and rear differential. This sound
occurs because of the structure of the
center differential. It does not indicate a
problem.
&
To change mode of driver ’s
control center differentialPress the “AUTO-MANU ”switch on the
center console to switch from auto mode
to manual mode or vice versa. When you
select the auto mode, the “AUTO ”indica-
tor light illuminates. When you select the
manual mode, the “AUTO”indicator light
turns off.
& Auto modeIn the auto mode, the system estimates
the driving and road conditions using
signals from the wheel speed sensor,
throttle position sensor, steering angle
sensor and brake switch, etc. According
to the result, it electronically and auto-
matically controls the degree of limitation
of the differential action (LSD torque) to
optimize the differential action of the
center differential. When the ignition
switch is turned ON, the “AUTO”indicator
light on the combination meter illuminates.
Starting and operating
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7

Black plate (288,1)
北米Model "A1110BE-C" EDITED: 2010/ 12/ 17
7-20
Starting and operating
The auto mode has 3 modes as follows.
Mode Operation
AUTO [+] This mode emphasizes traction control and strengthens the
limitation of differential action
that is suitable for driving on
slippery roads for vehicle stabi-
lity.
AUTO This mode is suitable for most driving situations.
AUTO [ ] This mode is suitable when you
seek quick response from the
steering wheel and smooth
driving.
! Mode setting method
In most situations, it is recommended that
the “AUTO ”mode is selected.Push the control switch forward to select the
“AUTO [+] ”mode. After setting the
mode, “
”on the combination meter
illuminates.
Pull the control switch rearward to select
the “AUTO [ ]” mode. After setting the
mode, “
”on the combination meter
illuminates.
When the “AUTO [+]”mode is selected,
pull the control switch rearward to change
to the “AUTO ”mode. When the “AUTO
[ ]” mode is set, push the control switch
forward to change to the “AUTO”mode.
& Manual modeIn the manual mode, you can use the
center differential control switch to adjust
the initial LSD torque as desired. When
this mode is selected, the “AUTO”indica-
tor light on the combination meter turns
off.

Black plate (289,1)
北米Model "A1110BE-C" EDITED: 2010/ 12/ 17
! Center differential control switch
and indicator lightThe control switch is located beside the
parking brake lever. By pushing the
control switch forward or pulling it rear-
ward, it is possible to change the initial
LSD torque.
The center differential indicator lights on
the combination meter give six levels of
indication. The indicator lights and control
switch are linked; when the switch is
pushed or pulled to change the initial
LSD torque, the illumination position of the
indicator lights changes accordingly.
Push the switch forward to increase the
initial LSD torque; when the “LOCK ”
indicator light illuminates, the initial LSD
torque setting is maximum. The center
differential will then be almost completely
locked.
Pull the switch rearward to reduce the
initial LSD torque. When the lowest posi-
tion of the driver ’s control center differen-
tial indicator light illuminates, the initial
LSD torque will be minimum. Under this
condition, only the Mechanical LSD torque
will limit the differential action.
CAUTION
. Do not operate the control switch
when a wheel slippage occurs.
Wait until the wheelspin has been
brought under control.
. Under any of the following con-
ditions after setting to the man-
ual mode, pull the center differ-
ential control switch to minimize
the initial LSD torque:
Starting and operating
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7

Black plate (290,1)
北米Model "A1110BE-C" EDITED: 2010/ 12/ 17
7-22
Starting and operating
. When a temporary spare tire is
installed
. When your vehicle is towed
. When the vehicle is stopped
with the manual mode se-
lected
NOTE. A higher initial LSD torque setting
gives the vehicle greater traction when
driving straight ahead but makes cor-
nering more difficult. Remember this
when adjusting the initial LSD torque.
In general, higher initial LSD torque
settings assist driving on slippery
roads and lower settings for non-slip-
pery roads. When the vehicle is stuck
in snow or mud, setting the initial LSD
torque to the maximum will help to free
the vehicle.
. The setting of the initial LSD torque
will remain even when the auto mode is
selected or the ignition switch is turned
to the “OFF ”position. However, the
initial LSD torque will be minimized
when the battery is disconnected and
reconnected.
. During cornering or when making
turns (especially when going into the
garage), the rotational difference be-
tween the front and rear wheels may cause a braking effect accompanied by
vibration and noise. This does not
indicate a problem. The phenomenon
will disappear when setting the initial
LSD torque to the minimum.
In the auto mode, it controls the initial
LSD torque automatically. While in the
auto mode, this phenomenon some-
times occurs depending on the driving
condition, however, it does not indicate
a problem.
.
Use the center differential indicator
light only as a rough indication of the
initial LSD torque.
. If you operate the center differential
control switch while quickly accelerat-
ing or turning a tight corner, you may
feel slight shocks. This is due to
differential action by the center differ-
ential and does not indicate a problem.
& Temporary releaseWhen the driver stops the vehicle and
pulls the parking brake lever after manu-
ally setting the initial LSD torque, the LSD
torque is temporarily minimized. However
the indicator on the combination meter
continues to show the driver ’s selected
initial LSD torque. When the driver re-
leases the parking brake lever, the initial
LSD torque set by the driver is restored.
Automatic transmissionThe automatic transmission is electroni-
cally controlled and provides 4 forward
speeds and 1 reverse speed. Also, it has a
manual mode and a SPORT mode.
WARNING
Do not shift from the “P ” or “N ”
position into the “D ” or “R ” position
while depressing the accelerator
pedal. This may cause the vehicle
to jump forward or backward.
CAUTION
. Shift into the “P ” or “R ” position
only after the vehicle is comple-
tely stopped. Shifting while the
vehicle is moving may cause
damage to the transmission.
. Do not race the engine for more
than 5 seconds in any position
except the “N ” or “P ” position
when the brake is set or when
chocks are used in the wheels.
This may cause the automatic
transmission fluid to overheat.
. Avoid shifting from one of the
forward driving positions into the

Black plate (304,1)
北米Model "A1110BE-C" EDITED: 2010/ 12/ 17
7-36
Starting and operating
The Vehicle Dynamics Control System
may therefore operate. Such operation
does not indicate a system malfunc-
tion.
–on gravel-covered or rutted
roads
– on unfinished roads
– when the vehicle is fitted with
snow tires or winter tires
. Activation of the Vehicle Dynamics
Control system will cause operation of
the steering wheel to feel slightly
different compared to that for normal
conditions.
. It is always important to reduce
speed when approaching a corner,
even if the vehicle is equipped with
Vehicle Dynamics Control.
. Always turn off the engine before
replacing a tire as failure to do so may
render the Vehicle Dynamics Control
system unable to operate correctly.& Vehicle Dynamics Control
system monitorRefer to “Vehicle Dynamics Control opera-
tion indicator light ”F 3-23 and “Vehicle
Dynamics Control warning light/Vehicle
Dynamics Control OFF indicator light/
Traction Control OFF indicator light (STI) ”
F 3-23.
& Vehicle Dynamics Control
mode switch (STI)Indicator lightVehicle Dynamics Control mode switchWhen the switch is pressed briefly or for
more than approximately 3 seconds dur- ing engine operation, the mode of the
Vehicle Dynamics Control System will be
changed.
!
Vehicle Dynamics Control mode
When the ignition switch is on, this mode
is selected.
This mode enables all controls for ABS,
the Traction Control System, and the
Vehicle Dynamics Control system. Select
this mode for most driving situations.
When this mode is selected, the indicator
light on the combination meter turns off.
! Traction mode
This mode restricts the functions of the
Traction Control System and Vehicle
Dynamics Control system and thus delays
utilizing their functions as a reaction to
vehicle behavior in comparison with the
Vehicle Dynamics Control mode. This
mode should be used in driving situations
where the vehicle dynamic performance
will improve without decreasing engine
torque control.
When the switch is pressed briefly during
engine operation, the indicator light on the
combination meter illuminates in green.
When the switch is pressed again to
reactivate the Vehicle Dynamics Control
system, the indicator light turns off.

Black plate (341,1)
北米Model "A1110BE-C" EDITED: 2010/ 12/ 17
12. Before putting the spare tire on, clean
the mounting surface of the wheel and hub
with a cloth.
13. Put on the spare tire. Replace the
wheel nuts. Tighten them by hand.
WARNING
Do not use oil or grease on the
wheel studs or nuts when the spare
tire is installed. This could cause the
nuts to become loose and lead to an
accident.
14. Turn the jack handle counterclockwise
to lower the vehicle.15. Use the wheel nut wrench to securely
tighten the wheel nuts to the specified
torque, following the tightening order in the illustration.
For the wheel nut tightening torque, refer
to
“Tires ”F 12-11. Never use your foot on
the wheel nut wrench or a pipe extension
on the wrench because you may exceed
the specified torque. Have the wheel nut
torque checked at the nearest automotive
service facility.
Turbo models
Non-turbo models16. Store the flat tire in the spare tire
compartment. Put in the spacer and tight-
en the attaching bolt firmly.
Also store the jack, jack handle and wheel
nut wrench in their storage locations.
WARNING
Never place a tire or tire changing
tools in the passenger compartment
after changing wheels. In a sudden
stop or collision, loose equipment
could strike occupants and cause
injury. Store the tire and all tools in
the proper place.
In case of emergency
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9

Black plate (397,1)
北米Model "A1110BE-C" EDITED: 2010/ 12/ 17
& Tire replacementThe wheels and tires are important and
integral parts of your vehicle’ s design;
they cannot be changed arbitrarily. The
tires fitted as standard equipment are
optimally matched to the characteristics
of the vehicle and were selected to give
the best possible combination of running
performance, ride comfort, and service
life. It is essential for every tire to have a
size and construction matching those
shown on the tire placard and to have a
speed symbol and load index matching
those shown on the tire placard.
Using tires of a non-specified size detracts
from controllability, ride comfort, braking
performance, speedometer accuracy and
odometer accuracy. It also creates incor-
rect body-to-tire clearances and inappro-
priately changes the vehicle ’sground
clearance.
All four tires must be the same in terms of
manufacturer, brand (tread pattern), con-
struction, and size. You are advised to
replace the tires with new ones that are
identical to those fitted as standard equip-
ment.
For safe vehicle operation, SUBARU
recommends replacing all four tires at
the same time.
WARNING
. All four tires must be the same in
terms of manufacturer, brand
(tread pattern), construction, de-
gree of wear, speed symbol, load
index and size. Mixing tires of
different types, sizes or degrees
of wear can result in damage to
vehicle ’s powertrain. Use of dif-
ferent types or sizes of tires can
also dangerously reduce con-
trollability and braking perfor-
mance and can lead to an acci-
dent.
. Use only radial tires. Do not use
radial tires together with belted
bias tires and/or bias-ply tires.
Doing so can dangerously re-
duce controllability, resulting in
an accident.& Wheel replacementWhen replacing wheels due, for example,
to damage, make sure the replacement
wheels match the specifications of the
wheels that are fitted as standard equip-
ment. Replacement wheels are available
from SUBARU dealers.
WARNING
Use only those wheels that are
specified for your vehicle. Wheels
not meeting specifications could
interfere with brake caliper opera-
tion and may cause the tires to rub
against the wheel well housing dur-
ing turns. The resulting loss of
vehicle control could lead to an
accident.NOTEWhen any of the wheels are removed
and replaced for tire rotation or to
change a flat tire, always check the
tightness of the wheel nuts after driv-
ing approximately 600 miles (1,000 km).
If any nut is loose, tighten it to the
specified torque.
Maintenance and service
11-37
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