2007 SUBARU IMPREZA WRX Owners Manual

Replacement of brake pad
and lining
The right front disc brake and the right rear
disc brake have audible wear indicators
on the brake pads. If the brake pads wear
close to their service limit, the wear
indicator makes a very audible scraping
noise when the brake pedal is applied.
If you hear this scraping noise each time
you apply the brake pedal, have the brake
pads serviced by your SUBARU dealer as
soon as possible.
CAUTION
If you continue to drive despite the
scraping noise from the audible
brake pad wear indicator, it will result in the need for costly brake
rotor repair or replacement.
& Breaking-in of new brake
pads and linings
When replacing the brake pad or lining,
use only genuine SUBARU parts. After
replacement, the new parts must be
broken in as follows: ! Brake pad and lining
While maintaining a speed of 30 to 40
mph (50 to 65 km/h), step on the brake
pedal lightly. Repeat this five or moretimes. ! Parking brake lining
1. Drive the vehicle at a speed of
approximately 22 mph (35 km/h).
2. With the parking brake release button
pushed in, pull the parking brake lever
SLOWLY and GENTLY. (Pulling with a
force of approximately 33 lbs [147 N, 15kg].)
3. Drive the vehicle for approximately
220 yards (200 meters) in this condition.
4. Wait 5 to 10 minutes for the parking
brake to cool down. Repeat this proce-dure.
5. Check the parking brake stroke. If the
parking brake stroke is out of the specified range, adjust it by turning the adjusting nut
located on the parking brake lever.
Parking brake stroke: 7–8 notches / 44 lbs (196 N, 20 kg)
WARNING
A safe location and situation should
be selected for break-in driving.
CAUTION
Pulling the parking brake lever too
forcefully may cause the rear
wheels to lock. To avoid this, be
certain to pull the lever up slowly
and gently. Maintenance and service
11-29

11-30Maintenance and service
Parking brake stroke
Check the parking brake stroke according
to the maintenance schedule in the“Warranty and Maintenance Booklet ”.
When the parking brake is properly
adjusted, braking power is fully applied
by pulling the lever up seven to eight
notches gently but firmly (approximately
44 lbs [196 N, 20 kg]). If the parking brake
lever stroke is not within the specified
range, have the brake system checked
and adjusted at your SUBARU dealer. Tires and wheels &
Types of tires
You should be familiar with type of tires
present on your vehicle.
The factory-fitted 17-inch tires on the
WRX-STI are summer tires. The factory-
fitted tires on other versions are all-seasontires. ! All season tires
All season tires are designed to provide
an adequate measure of traction, handling
and braking performance in year-round
driving including snowy and icy road
conditions. However all season tires do
not offer as much traction performance as
winter (snow) tires in heavy or loose snow
or on icy roads.
All season tires are identified by “ALL
SEASON ”and/or “M+S ”(Mud & Snow) on
the tire sidewall. ! Summer tires
Summer tires are high-speed capability
tires best suited for highway driving under
dry conditions.
Summer tires are inadequate for driving
on slippery roads such as on snow-
covered or icy roads.
If you drive your vehicle on snow-covered
or icy roads, we strongly recommend the use of winter (snow) tires.
When installing winter tires, be sure to
replace all four tires. !
Winter (snow) tires
Winter tires are best suited for driving on
snow-covered and icy roads. However
winter tires do not perform as well as
summer tires and all season tires on roads
other than snow-covered and icy roads. & 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. 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. Maintenance and service
11-31
– CONTINUED –

11-32Maintenance and service
.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 and for the
vehicle when towing a trailer, 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
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 markExample 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. Maintenance and service
11-33
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11-34Maintenance and service
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 unidirectional tires
1) Front
Vehicles equipped with 4 non-unidirec-
tional 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 (12,500
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 become loose. &
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 ’s ground
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. 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.. Be sure to fit tire chains on uniformly
and completely around the tire, otherwise
the chains may scratch the wheel. . When wheel nuts, balance weights, or
the center cap is replaced, be sure to
replace them with genuine SUBARU parts
designed for aluminum wheels. Maintenance and service
11-35

11-36Maintenance and service
Intercooler water spray (WRX-STI)
Add water to the intercooler water spray
tank when the intercooler water spray
warning light in the combination meter
comes on. The warning light comes on
when the water in the tank has decreased
to approximately 0.4 liters (0.4 US qt, 0.4
Imp qt).
The tank is located on the right-hand side
of the trunk. NOTE .Use only pure water for refilling.
. In cold weather (when you do not
use the intercooler water spray), keep
the tank half-empty in case the water
freezes. A larger amount of water could
break the tank if it froze. 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.