2005 SUBARU IMPREZA four wheel drive

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Starting and operating
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State emission testing (U.S. only)
At state inspection time, remember to tell your in-
spection or service station in advance not to place
your Subaru AWD vehicle on a two-wheel dyna-
mometer. Otherwise, serious transmission dam-
age will result.
Some states have started using dynamometers in
their state inspection programs in order to meet their
obligation under federal law to implement stricter vehi-
cle emission standards to reduce air pollution from ve-
hicles. A dynamometer is a treadmill or roller-like test-
ing device that allows your vehicle’s wheels to turn
while the vehicle remains in one place. Depending on
the severity of a state’s air pollution problems, the
states must adopt either a “basic” or “enhanced” vehi-
cle emission inspection test. Normally, a portion of the
basic emission test consists of an emission inspector
inserting an analyzer probe into the exhaust pipe of an
idling vehicle for a short period of time. States with
more severe air pollution problems are required to
adopt an enhanced vehicle emission test. This test
simulates actual driving conditions on a dynamometer
and permits more accurate measurement of tailpipe
emitted pollution than the basic emission test.
The U.S. Environmental Protection Agency (EPA) and states using two-wheel dynamometers in their emis-
sion testing programs have
EXEMPTED Subaru AWD
vehicles from the portion of the testing program that in-
volves a two-wheel dynamometer.
There are some states that use four-wheel dynamom-
eters in their testing programs. When properly used,
that equipment will not damage an AWD Subaru vehi- cle.
Under no circumstances should the rear wheels be
jacked off the ground, nor should the driveshaft be dis-
connected for state emission testing.
Testing of an All-Wheel Drive vehicle must
NEVER be performed on a single two-wheel dy-
namometer. Attempting to do so will result in
uncontrolled vehicle movement and may cause
an accident or injuries to persons nearby.
Resultant vehicle damage due to improper test-
ing is not covered under the SUBARU Limited
Warranty and is the responsibility of the state

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Driving tips
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Driving tips for AWD vehicles
All wheel drive distributes the engine power to all four
wheels. AWD vehicles provide better traction when
driving on slippery, wet or snow-covered roads and
when moving out of mud, dirt and sand. By shifting
power between the front and rear wheels, SUBARU
AWD can also provide added traction during acceler-
ation and added engine braking force during deceler-
ation.
Therefore, your SUBARU AWD vehicle may handle
differently than an ordinary two wheel drive vehicle
and it contains some features unique to AWD. For safety purposes as well as to avoid damaging the
AWD system, you should keep the following tips inmind: y
An AWD vehicle is better able to climb steeper
roads under snowy or slippery conditions than a two
wheel drive vehicle. There is little difference in han-
dling, however, during extremely sharp turns or sud-
den braking. Therefore, when driving down a slope or
turning corners, be sure to reduce your speed and
maintain an ample distance from other vehicles. y When replacing a tire, make sure you use only the
same size, construction, brand, and load range as the
original tires listed on the tire placard. Using other siz-
es, circumference or construction may result in severe
mechanical damage to the drive train of your vehicle
and may affect ride, handling, braking, speedometer/
odometer calibration, and clearance between the body
and tires. It also may be dangerous and lead to loss of
vehicle control. y If you use a temporary spare tire to replace a flat
tire, be sure to use the original temporary spare tire
stored in the vehicle. Using other sizes may result in
severe mechanical damage to the drive train of your
vehicle. y Always check the cold tire pressure before starting
to drive. The recommended tire pressure is provided
on the tire placard, which is located under the door
HS8003BA

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Driving tips
dent.
Your vehicle is equipped with “summer tires” as origi-
nal equipment, which are inadequate for driving on
slippery roads such as on snow-covered or icy roads.
Compared with winter and all-season tires, summer
tires give significantly less grip on snowy and icy road
surfaces. Therefore, use of winter tires is strongly rec-
ommended when driving with such road conditions.
When you choose to install winter tires on your vehi-
cle, be sure to use the correct tire size and type. You
must install four winter tires that are of the same size,
construction, brand and load range and you should
never mix radial, belted bias or bias tires since this
may result in dangerous handling characteristics.
When you choose a tire, make sure that there is
enough clearance between the tire and vehicle body.
Remember to drive with care at all times regardless of
the type of tires on your vehicle. „ Tire chains
Driving on snowy grades or icy roads may require the
use of tire chains, in which case put the chains on the
front wheels only. Use only SAE class S type chains
that are of the correct size for your tires so as not to damage the vehicle body or suspension.
When driving with tire chains, drive at speeds below
19 mph (30 km/h).
When a temporary spare tire is on a front wheel, re-
place the temporary spare tire with the rear tire on the
same side of the vehicle, and then fit chains on the
front tires.
Always use the utmost care when driving with tire
chains — overconfidence because you are driving
with tire chains could easily lead to a serious accident.
Tire chains cannot be used on tires listed below
because of lack of clearance between the tires
and vehicle body.y
225/45R17 tires for WRX-STi
yOptional 215/45R17 tires for WRX
„ Rocking the vehicle
If you must rock the vehicle to free it from snow, sand,
or mud, depress the accelerator pedal slightly and
move the selector lever back and forth between “D”
and “R” repeatedly. Do not race the engine. For the
best possible traction, avoid spinning the wheels when

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Maintenance and service
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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-season tires. The 17-inch tires that can be deal-
er-fitted on the WRX as an option are summer tires. T All season tires
All season tires are designed to provide an adequate
measure of traction, handling and braking perfor-
mance 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. T Summer tires
Summer tires are high-speed capability tires best suit-
ed 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. T
Winter (snow) tires
Winter tires are best suited for driving on snow-cov-
ered and icy roads. However winter tires do not per-
form 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 se-
rious damage, nails, and stones. At the same time,
check the tires for abnormal wear.
Contact your SUBARU dealer immediately if you find
any problem.
NOTE y When the wheels and tires strike curbs or are
subjected to harsh treatment as when the vehicle
is driven on a rough surface, they can suffer dam-
age 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, pot-
holes or on other rough surfaces. If doing so is un-
avoidable, 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