SUBARU IMPREZA WRX 2011 4.G Owners Manual

11-18Maintenance and service
case.
3. Loosen the screw of the clamp and
pull the air intake boot out of the air
cleaner case.
4. Unsnap the two clips holding the air
cleaner case cover.
5. Open the air cleaner case and remove
the air cleaner element.
6. Clean the inside of the air cleaner case
and case cover with a damp cloth and
install a new air cleaner element.
7. To install the air cleaner case, insert
the three projections on the air cleaner
case into the slits on the air cleaner case
cover.
8. Install in the reverse order of removal. !
Turbo models
1. Use a screwdriver to undo the clips on
the air intake duct, then remove the air
intake duct.
1) Connector
2) Clip

2. Unplug the connector that is attached
to the top of the air cleaner case.
3. Unsnap the two clips holding the air
cleaner case cover.
4. Open the air cleaner case and remove
the air cleaner element.
5. Clean the inside of the air cleaner case
and case cover with a damp cloth and
install a new air cleaner element.
6. If the air cleaner case has been
removed, insert the three projections on
the air cleaner case into the slits on the air
cleaner case cover.
7. Install in the reverse order of removal.Spark plugs
It may be difficult to replace the spark
plugs. It is recommended that you have
the spark plugs replaced by your
SUBARU dealer.
The spark plugs should be replaced
according to the maintenance schedule
in the
“Warranty and Maintenance Book-
let ”.
CAUTION
. When disconnecting the spark
plug cables, always grasp the
spark plug cap, not the cables.
. Make sure the cables are re-
placed in the correct order. Maintenance and service
11-19
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11-20Maintenance and service
&Recommended spark plugs
For the recommended spark plugs, refer to “Electrical system ”F 12-3. Drive belts
1) Power steering oil pump pulley
2) Front side belt
3) Alternator pulley
4) Air conditioner compressor pulley
5) Rear side belt
6) Crank pulley
A) 22 lbf (98 N, 10 kgf)
CAUTION
The front side belt, which runs in
conjunction with the following com-
ponents, must be used within the
specified deflection. . Power steering oil pump pulley
. Alternator pulley
. Crank pulley Check the deflection of the front
side belt and if there is any loosen-
ess, cracks, wear or unusual noise
on the front side belt, contact your
SUBARU dealer.
Continuing to use the vehicle with
the belt outside of the specification
may cause the engine to malfunc-
tion and the above components tomalfunction.
To check the deflection of the front side
belt, place a straightedge (ruler) across
two adjacent pulleys (alternator pulley and
crank pulley) and apply a force of 22 lbf
(98 N, 10 kgf) midway between the pulleys
by using a spring scale. The belt deflec-
tion should be the amount specified. If the
front side belt is loose, cracked or worn,
contact your SUBARU dealer. in (mm)
Deflection
New belt Used belt
A 0.28
–0.35
(7.0 –9.0) 0.35
–0.43
(9.0 –11.0)
The rear side belt is a stretch-type belt,
therefore the deflection does not need to
be checked. If there are cracks or wear
confirmed on the belts and a squeaking
noise is heard from them, contact your
SUBARU dealer.

Manual transmission oil &Checking the oil level
Non-turbo models
1) Yellow handle
Turbo models except STI Check the oil level monthly.
1. Park the vehicle on a level surface and
stop the engine.
2. Pull out the level gauge, wipe it clean,
and insert it again.
1) Upper level
2) Lower level
3. Pull out the level gauge again and
check the oil level on it. If it is below the
lower level, add oil through the level
gauge hole to bring the level up to the
upper level.
CAUTION
Be careful not to spill manual trans-
mission oil when adding it. If oil
touches the exhaust pipe, it may
cause a bad smell, smoke, and/or a
fire. If oil gets on the exhaust pipe,
be sure to wipe it off.
NOTE
There is no transmission oil level
gauge for STI. Consult your SUBARU
dealer to check the oil level. & Recommended grade and viscosity
Each oil manufacturer has its own base
oils and additives. Never use different
brands together. For details, refer to“ Manual transmission, front differential
and rear differential gear oil ”F 12-8.
Maintenance and service
11-21

11-22Maintenance and service
Automatic transmission fluid &Checking the fluid level
The automatic transmission fluid expands
largely as its temperature rises; the fluid
level differs according to fluid temperature.
Therefore, there are two different scales
for checking the level of hot fluid and cold
fluid on the level gauge.
Though the fluid level can be checked
without warming up the fluid on the“ COLD ”range, it is recommended to
check the fluid level when the fluid is at
operating temperature. ! Checking the fluid level when the
fluid is hot
1. Drive the vehicle several miles to raise
the temperature of the transmission fluid
up to normal operating temperature; 158
to 176 8F (70 to 80 8C) is normal.
2. Park the vehicle on a level surface and
set the parking brake.
3. First shift the select lever in each
position. Then shift it in the “P ” position,
and run the engine at idling speed.
1) Yellow handle
1) HOT range
2) COLD range
3) Upper level
4) Lower level
4. Pull out the level gauge and check the fluid level on the gauge. If it is below the
lower level on the
“HOT ”range, add the
recommended automatic transmission
fluid up to the upper level. ! Checking the fluid level when the
fluid is cold
When the fluid level has to be checked
without time to warm up the automatic
transmission, check to see that the fluid
level is between the lower level and upper
level on the “COLD ”range. If it is below
that range, add fluid up to the upper level.
Be careful not to overfill.
CAUTION
Be careful not to spill automatic
transmission fluid when adding it.
If automatic transmission fluid
touches the exhaust pipe, it may
cause a bad smell, smoke, and/or a
fire. If automatic transmission fluid
gets on the exhaust pipe, be sure to
wipe it off.

&Recommended fluid
Refer to “Fluids ”F 12-9.
NOTE
For optimum transmission perfor-
mance, only use the automatic trans-
mission fluid that is recommended and
provided by SUBARU.
If the recommended automatic trans-
mission fluid is unavailable, Dexron III
may be temporarily used. If the Dexron
III is used continuously there will be a
noticeable increase in the vibration and
noise from the automatic transmission. Front differential gear oil (AT models) &
Checking the oil level
1) Yellow handle
1. Park the vehicle on a level surface and
stop the engine.
2. Pull out the level gauge, wipe it clean,
and insert it again.
1) Upper level
2) Lower level
3. Pull out the level gauge again and
check the oil level on it. If it is below the
lower level, add oil to bring the level up to
the upper level.
CAUTION
Be careful not to spill front differ-
ential gear oil when adding it. If oil
touches the exhaust pipe, it may
cause a bad smell, smoke, and/or a
fire. If oil gets on the exhaust pipe,
be sure to wipe it off. Maintenance and service
11-23
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11-24Maintenance and service
&Recommended grade and viscosity
Each oil manufacturer has its own base
oils and additives. Never use different
brands together. For details, refer to“ Manual transmission, front differential
and rear differential gear oil ”F 12-8. Rear differential gear oil
There is no rear differential gear oil level
gauge. To check the rear differential gear
oil level, we recommend that you consult
your SUBARU dealer for inspection. &
Recommended grade and viscosity
Each oil manufacturer has its own base
oils and additives. Never use different
brands together. For details, refer to“ Manual transmission, front differential
and rear differential gear oil ”F 12-8. Power steering fluid &
Checking the fluid level
The power steering fluid expands greatly
as its temperature rises; the fluid level
differs according to fluid temperature.
Therefore, the reservoir tank has two
different checking ranges for hot and cold fluids.
Check the power steering fluid level
monthly.
1. Park the vehicle on a level surface,
and stop the engine.

2. Check the fluid level of the reservoir tank.
When the fluid is hot after the vehicle has
been run: Check that the oil level isbetween“HOT MIN ”and “HOT MAX ”on
the surface of the reservoir tank.
When the fluid is cool before the vehicle is
run: Check that the oil level is between“ COLD MIN ”and “COLD MAX ”on the
surface of the reservoir tank.
3. If the fluid level is lower than the
applicable “MIN ”line, add the recom-
mended fluid as necessary to bring the
level between the “MIN ”and “MAX ”line.
If the fluid level is extremely low, it may
indicate possible leakage. Consult your
SUBARU dealer for an inspection.
WARNING
Be careful not to burn yourself
because the fluid may be hot.
CAUTION
. When power steering fluid is
being added, use only clean fluid,
and be careful not to allow any
dirt into the tank. And never use
different brands together.
. Be careful not to spill power
steering fluid when adding it. If
power steering fluid touches the
exhaust pipe, it may cause a bad
smell, smoke, and/or a fire. If
power steering fluid gets on the
exhaust pipe, be sure to wipe it off.
& Recommended fluid
Refer to “Fluids ”F 12-9. Brake fluid &
Checking the fluid level
1) “MAX ”level mark
2) “MIN ”level mark
Check the fluid level monthly.
Check the fluid level on the outside of the
reservoir. If the level is below “MIN ”, add
the recommended brake fluid to “MAX ”.
Use only brake fluid from a sealed
container.
WARNING
. Never let brake fluid contact your
eyes because brake fluid can be
harmful to your eyes. If brake
fluid gets in your eyes, immedi-
ately flush them thoroughly with Maintenance and service
11-25
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11-26Maintenance and service
clean water. For safety, when
performing this work, wearing
eye protection is advisable.
. Brake fluid absorbs moisture
from the air. Any absorbed moist-
ure can cause a dangerous loss
of braking performance.
. If the vehicle requires frequent
refilling, there may be a leak. If
you suspect a problem, have the
vehicle checked at your SUBARU
dealer.
CAUTION
. When adding brake fluid, be care-
ful not to allow any dirt into the
reservoir.
. Never splash the brake fluid over
painted surfaces or rubber parts.
Alcohol contained in the brake
fluid may damage them.
. Be careful not to spill brake fluid
when adding it. If brake fluid
touches the exhaust pipe, it may
cause a bad smell, smoke, and/or
a fire. If brake fluid gets on the
exhaust pipe, be sure to wipe itoff. &
Recommended brake fluid
Refer to “Fluids ”F 12-9.
CAUTION
Never use different brands of brake
fluid together. Also, avoid mixing
DOT 3 and DOT 4 brake fluids even if
they are the same brand. Clutch fluid (MT models) &
Checking the fluid level
Check the fluid level on the outside of the
reservoir. If the level is below “MIN ”level
mark, add the recommended clutch fluidto “MAX ”level mark.
Use only clutch fluid from a sealed
container.
WARNING
Never let clutch fluid contact your
eyes because clutch fluid can be
harmful to your eyes. If clutch fluid
gets in your eyes, immediately flush
them thoroughly with clean water.
For safety, when performing this
work, wearing eye protection is

advisable.
CAUTION
. Clutch fluid absorbs moisture
from the air. Any absorbed moist-
ure can cause improper clutchoperation.
. If the vehicle requires frequent
refilling, there may be a leak. If
you suspect a problem, have the
vehicle checked at your SUBARU
dealer.
. When clutch fluid is added, be
careful not to allow any dirt into
the tank.
. Never splash the clutch fluid over
painted surfaces or rubber parts.
Alcohol contained in the clutch
fluid may damage them.
. Be careful not to spill clutch fluid
when adding it. If clutch fluid
touches the exhaust pipe, it may
cause a bad smell, smoke, and/or
a fire. If clutch fluid gets on the
exhaust pipe, be sure to wipe itoff. &
Recommended clutch fluid
Refer to “Fluids ”F 12-9.CAUTION
Never use different brands of clutch
fluid together. Also, avoid mixing
DOT 3 and DOT 4 brake fluids even if
they are the same brand. Brake booster
If the brake booster does not operate as
described in the following, have it checked
by your SUBARU dealer.
1. With the engine off, depress the brake
pedal several times, applying the same
pedal force each time. The distance the
pedal travels should not vary.
2. With the brake pedal depressed, start
the engine. The pedal should move
slightly down to the floor.
3. With the brake pedal depressed, stop
the engine and keep the pedal depressed
for 30 seconds. The pedal height should
not change.
4. Start the engine again and run for
approximately one minute then turn it off.
Depress the brake pedal several times to
check the brake booster. The brake
booster operates properly if the pedal
stroke decreases with each depression. NOTE
For vehicles equipped with the brake
assist system, when you depress the
brake pedal strongly or suddenly, the
following phenomena occur. However,
even though these occur, they do not
indicate any malfunctions, and the
brake assist system is operating prop-Maintenance and service
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