2011 SUBARU IMPREZA Owners Manual

11-32Maintenance and service
temperature outside. By way of example,
the following table shows the required tire
pressures that correspond to various out-
side temperatures when the temperature
in the garage is 60 8F (15.6 8C).
Example:
Tire size: P205/55R16 89V and
P205/50R17 88V
Standard tire pressures:
Front: 33 psi (230 kPa, 2.3 kgf/cm
2)
Rear: 32 psi (220 kPa, 2.2 kgf/cm2)
Garage temperature: 60 8F (15.6 8C)
Outside
temperature Adjusted pressure
[psi (kPa, kgf/cm
2)]
Front Rear
30 8F( 18C) 36 (250, 2.5) 35 (240, 2.4)
10 8F( 12 8C) 38
(265, 2.65) 37
(255, 2.55)
10 8F( 23 8C) 40 (280, 2.8) 39 (270, 2.7)
If the low tire pressure warning light
illuminates when you drive the vehicle in
cold outside air after adjusting the tire
pressures in a warm garage, re-adjust the
tire pressures using the method described
above. Then, increase the vehicle speed
to at least 20 mph (32 km/h) and check to
see that the low tire pressure warning light
turns off a few minutes later. If the low tire
pressure warning light does not turn off, the tire pressure monitoring system may
not be functioning normally. In this event,
go to a SUBARU dealer to have the
system inspected as soon as possible.
While the vehicle is driven, friction be-
tween tires and the road surface causes
the tires to warm up. After illumination of
the low tire pressure warning light, any
increase in the tire pressures caused by
an increase in the outside air temperature
or by an increase in the temperature in the
tires can cause the low tire pressure
warning light to turn off.
System resetting is necessary when the
wheels are changed (for example, a
switch to snow tires) and new TPMS
valves are installed on the newly fitted
wheels. Have this work performed by a
SUBARU dealer following wheel replace-ment.
It may not be possible to install TPMS
valves on certain wheels that are on the
market. Therefore, if you change the
wheels (for example, a switch to snow
tires), use wheels that have the same part
number as the standard-equipment
wheels. Without four operational TPMS
valve/sensors on the wheels, the TPMS
will not fully function and the warning light
on the combination meter will illuminate
steadily after blinking for approximatelyone minute.
When a tire is replaced, adjustments are
necessary to ensure continued normal
operation of the tire pressure monitoring
system. As with wheel replacement, there-
fore, you should have the work performed
by a SUBARU dealer.
WARNING
If the low tire pressure warning light
does not illuminate briefly after the
ignition switch is turned ON or the
light illuminates steadily after blink-
ing for approximately one minute,
you should have your Tire Pressure
Monitoring System checked at a
SUBARU dealer as soon as possi-ble.
If this light illuminates while driving,
never brake suddenly and keep
driving straight ahead while gradu-
ally reducing speed. Then slowly
pull off the road to a safe place.
Otherwise an accident involving
serious vehicle damage and serious
personal injury could occur.
If this light still illuminates while
driving after adjusting the tire pres-
sure, a tire may have significant
damage and a fast leak that causes
the tire to lose air rapidly. If you have

a flat tire, replace it with a spare tire
as soon as possible.
When a spare tire is mounted or a
wheel rim is replaced without the
original pressure sensor/transmitter
being transferred, the low tire pres-
sure warning light will illuminate
steadily after blinking for approxi-
mately one minute. This indicates
the TPMS is unable to monitor all
four road wheels. Contact your
SUBARU dealer as soon as possible
for tire and sensor replacement and/
or system resetting. If the light
illuminates steadily after blinking
for approximately one minute,
promptly contact a SUBARU dealer
to have the system inspected.
& Tire inspection
Check on a daily basis that the tires are
free from serious damage, nails, and
stones. At the same time, check the tires
for abnormal wear.
Contact your SUBARU dealer immedi-
ately if you find any problem. NOTE . When the wheels and tires strike
curbs or are subjected to harsh treat-
ment as when the vehicle is driven on a rough surface, they can suffer damage
that cannot be seen with the naked eye.
This type of damage does not become
evident until time has passed. Try not
to drive over curbs, potholes or on
other rough surfaces. If doing so is
unavoidable, keep the vehicle
’s speed
down to a walking pace or less, and
approach the curbs as squarely as
possible. Also, make sure the tires are
not pressed against the curb when you
park the vehicle.. If you feel unusual vibration while
driving or find it difficult to steer the
vehicle in a straight line, one of the
tires and/or wheels may be damaged.
Drive slowly to the nearest authorized
SUBARU dealer and have the vehicleinspected.
& Tire pressures and wear
Maintaining the correct tire pressures
helps to maximize the tires ’service lives
and is essential for good running perfor-
mance. Check and, if necessary, adjust
the pressure of each tire (including the
spare) at least once a month (for example,
during a fuel stop) and before any long
journey.
Check the tire pressures when the tires
are cold. Use a pressure gauge to adjust
the tire pressures to the values shown on
the tire placard. The tire placard is located
on the door pillar on the driver ’s side.
Driving even a short distance warms up
the tires and increases the tire pressures.
Also, the tire pressures are affected by the
outside temperature. It is best to check tire
pressure outdoors before driving thevehicle.
When a tire becomes warm, the air inside
it expands, causing the tire pressure to
increase. Be careful not to mistakenly
release air from a warm tire to reduce itspressure. Maintenance and service
11-33
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11-34Maintenance and service
NOTE .The air pressure in a tire increases
by approximately 4.3 psi (30 kPa, 0.3 kgf/cm
2) when the tire becomes warm.
. The tires are considered cold when
the vehicle has been parked for at least
three hours or has been driven less
than one mile (1.6 km).
WARNING
Do not let air out of warm tires to
adjust pressure. Doing so will result
in low tire pressure.
Incorrect tire pressures detract from con-
trollability and ride comfort, and they
cause the tires to wear abnormally. .
Correct tire pressure (tread worn
evenly)
Roadholding is good, and steering is
responsive. Rolling resistance is low, so
fuel consumption is also lower. .
Abnormally low tire pressure (tread
worn at shoulders)Rolling resistance is high, so fuel con-
sumption is also higher.

.Abnormally high tire pressure (tread
worn in center)
Ride comfort is poor. Also, the tire
magnifies the effects of road-surface
bumps and dips, possibly resulting in
vehicle damage.
If the tire placard shows tire pressures for
the vehicle when fully loaded, adjust the
tire pressures to the values that match
current loading conditions.
WARNING
Driving at high speeds with exces-
sively low tire pressures can cause
the tires to deform severely and to
rapidly become hot. A sharp in-
crease in temperature could cause
tread separation, and destruction of the tires. The resulting loss of
vehicle control could lead to anaccident.
& Wheel balance
Each wheel was correctly balanced when
your vehicle was new, but the wheels will
become unbalanced as the tires become
worn during use. Wheel imbalance causes
the steering wheel to vibrate slightly at
certain vehicle speeds and detracts from
the vehicle ’s straight-line stability. It can
also cause steering and suspension sys-
tem problems and abnormal tire wear. If
you suspect that the wheels are not
correctly balanced, have them checked
and adjusted by your SUBARU dealer.
Also have them adjusted after tire repairs
and after tire rotation. NOTE
Loss of correct wheel alignment*
causes the tires to wear on one side
and reduces the vehicle ’s running
stability. Contact your SUBARU dealer
if you notice abnormal tire wear.
*: The suspension system is designed to hold
each wheel at a certain alignment (relative to
the other wheels and to the road) for optimum
straight-line stability and cornering perfor- mance. &
Wear indicators
1) New tread
2) Worn tread
3) Tread wear indicator
Each tire incorporates a tread wear
indicator, which becomes visible when
the depth of the tread grooves decreases
to 0.063 in (1.6 mm). A tire must be
replaced when the tread wear indicator
appears as a solid band across the tread.
WARNING
When a tire ’s tread wear indicator
becomes visible, the tire is worn
beyond the acceptable limit and
must be replaced immediately. With
a tire in this condition, driving at
high speeds in wet weather can Maintenance and service
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11-36Maintenance and service
cause the vehicle to hydroplane.
The resulting loss of vehicle control
can lead to an accident.
NOTE
For safety, inspect tire tread regularly
and replace the tires before their tread
wear indicators become visible. & Tire rotation direction mark
Example of tire rotation direction mark
1) Front
If the tire has the rotation direction
specification, the tire rotation direction
mark is placed on its sidewall.
When you install a tire that has the tire
rotation direction mark, install the tire with the direction mark facing forward.
& Tire rotation
Vehicles equipped with 4 non-unidirec-
tional tires
1) Front
Vehicles equipped with unidirectional tires
1) Front
Tire wear varies from wheel to wheel. To
maximize the life of each tire and ensure
that the tires wear uniformly, it is best to
rotate the tires every 7,500 miles (12,000
km). Move the tires to the positions shown
in the illustration each time they arerotated.
Replace any damaged or unevenly worn
tires at the time of rotation. After tire
rotation, adjust the tires pressures and
make sure the wheel nuts are correctlytightened.
After driving approximately 600 miles
(1,000 km), check the wheel nuts again
and retighten any nut that has becomeloose.

&Tire replacement
The 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 tovehicle ’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 replacement
When 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 anaccident.
NOTE
When 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

11-38Maintenance and service
Aluminum wheels
Aluminum wheels can be scratched and
damaged easily. Handle them carefully to
maintain their appearance, performance,
and safety. .When 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 driving approximately
600 miles (1,000 km). If any nut is loose,
tighten it to the specified torque. . Never apply oil to the threaded parts,
wheel nuts, or tapered surface of the wheel. . Never let the wheel rub against sharp
protrusions or curbs.. When wheel nuts, balance weights, or
the center cap is replaced, be sure to
replace them with genuine SUBARU parts
designed for aluminum wheels. Windshield washer fluid
If you spray washer fluid on the windshield
but the supply of washer fluid appears to
diminish, check the level of washer fluid in
the tank.
Washer fluid level gauge
Remove the washer tank filler cap, then
check the fluid level indicated by the level
gauge (attached to the inside of the cap).
If the level is near the
“Low ”mark, add
fluid until it reaches the “Hi ”level on the

level gauge or the“FULL ”mark on the
tank.
Use windshield washer fluid. If windshield
washer fluid is unavailable use clean
water.
In areas where water freezes in winter,
use an anti-freeze type windshield washer
fluid. SUBARU Windshield Washer Fluid
contains 58.5% methyl alcohol and 41.5%
surfactant, by volume. Its freezing tem-
perature varies according to how much it
is diluted, as indicated in the followingtable.
Washer Fluid
Concentration Freezing
Temperature
30% 10.48F( 12 8C)
50% 48F( 20 8C)
100% 49 8F( 45 8C)
CAUTION
Never use engine coolant as washer
fluid because it could cause paintdamage.
In order to prevent freezing of washer
fluid, check the freezing temperatures in
the table above when adjusting the fluid
concentration to the outside temperature.
If you fill the reservoir tank with a fluid with a different concentration from the one
used previously, purge the old fluid from
the piping between the reservoir tank and
washer nozzles by operating the washer
for a certain period of time. Otherwise, if
the concentration of the fluid remaining in
the piping is too low for the outside
temperature, it may freeze and block thenozzles.
CAUTION
. Adjust the washer fluid concen-
tration appropriately for the out-
side temperature. If the concen-
tration is inappropriate, sprayed
washer fluid may freeze on the
windshield and obstruct your
view, and the fluid may freeze in
the reservoir tank.
. State or local regulations on
volatile organic compounds may
restrict the use of methanol, a
common windshield washer anti-
freeze additive. Washer fluids
containing non-methanol anti-
freeze agents should be used
only if they provide cold weather
protection without damaging
your vehicle ’s paint, wiper blades
or washer system. Replacement of wiper blades
Grease, wax, insects, or other material on
the windshield or the wiper blade results in
jerky wiper operation and streaking on the
glass. If you cannot remove the streaks
after operating the windshield washer or if
the wiper operation is jerky, clean the
outer surface of the windshield (or rear
window) and the wiper blades using a
sponge or soft cloth with a neutral
detergent or mild-abrasive cleaner. After
cleaning, rinse the windshield and wiper
blades with clean water. The windshield is
clean if beads do not form when you rinse
the windshield with water.
CAUTION
. Do not clean the wiper blades
with gasoline or a solvent, such
as paint thinner or benzine. This
will cause deterioration of the
wiper blades.
. While removing the wiper blades
from the wiper arms, do not
return the wiper arms to the
original positions. Otherwise,
the windshield surface may bescratched.
. When returning the raised wiper
arms to the original positions, Maintenance and service
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