2004 SUBARU IMPREZA WRX transmission oil

3-22
Instruments and controls
Do not operate the engine with the oil pressure
warning light on. This may cause serious en-
gine damage.
! AT OIL TEMPerature warning
light (for AT vehicles)
If this light comes on when the engine is running, it
may indicate that the automatic transmission fluid tem-
perature is too hot.
If the light comes on while driving, it is unnecessary to
stop the vehicle, but avoid driving up steep grades or
in stop and go traffic. ! Automatic transmission control system warn-
ing
If the light flashes after the engine starts, it may indi-
cate that the automatic transmission control system is
not working properly. Contact your nearest SUBARU
dealer for service immediately. !
Rear differential oil temperature
warning light (WRX-STi)
Reduce vehicle speed and park the vehicle in a
safe place as soon as possible if the R.DIFF
TEMP light comes on. Continued driving with
this light on can damage the rear differential
and other parts of the powertrain.
If this light comes on 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 ra-
tio setting and adopts its minimum ratio.
If the light comes on while driving, reduce vehicle
speed and stop the vehicle at the nearest safe place.
Park the vehicle for several minutes. After the light
goes out, you can start driving.
If the light does not go out, contact the neares
SUBARU dealer for service.
NOTE " If the tire pressures are not correct and/or the

7-9
Starting and operating
– CONTINUED –
Preparing to drive
You should perform the following checks and adjust-
ments every day before you start driving.
1. Check that all windows, mirrors, and lights are
clean and unobstructed.
2. Check the appearance and condition of the tires.
Also check tires for proper inflation.
3. Look under the vehicle for any sign of leaks.
4. Check that the hood, trunk and rear gate are fully
closed.
5. Check the adjustment of the seat.
6. Check the adjustment of the inside and outside mir-
rors.
7. Fasten your seatbelt. Check that your passengers
have fastened their seatbelts.
8. Check the operation of the warning and indicator
lights when the ignition switch is turned to the “ON” po-sition.
9. Check the gauges, indicator and warning lights af-
ter starting the engine.
NOTE
Engine oil, engine coolant, brake fluid, washer flu-
id and other fluid levels should be checked daily,
weekly or at fuel stops.
Starting the engine
Do not operate the starter motor continuously
for more than ten seconds. If the engine fails to
start after operating the starter for five to ten
seconds, wait for ten seconds or more before
trying again.
! Manual transmission vehicle
1. Apply the parking brake.
2. Turn off unnecessary lights and accessories.
3. Press the clutch pedal to the floor and shift the shift
lever into neutral. Hold the clutch pedal to the floor
while starting the engine.
The starter motor will only operate when the clutch
pedal is pressed fully to the floor.
4. Turn the ignition switch to the “ON” position and
check the operation of the warning and indicator lights.
Refer to the “Warning and indicator lights” section (chapter 3).
5. Turn the ignition switch to the “START” position
without depressing the accelerator pedal. Release
the key immediately after the engine has started.

8-10
Driving tips
shallow streams, first check the depth of the water and
the bottom of the stream bed for firmness and ensure
that the bed of the stream is flat. Drive slowly and com-
pletely through the stream. The water should be shal-
low enough that it does not reach the vehicle’s under-
carriage. Water entering the engine air intake or the
exhaust pipe or water splashing onto electrical parts
may damage your vehicle and may cause it to stall.
Never attempt to drive through rushing water; regard-
less of its depth, it can wash away the ground from un-
der your tires, resulting in possible loss of traction and
even vehicle rollover. "
Always check your brakes for effectiveness immedi-
ately after driving in sand, mud or water. Do this by
driving slowly and stepping on the brake pedal. Re-
peat that process several times to dry out the brake
discs and brake pads. " Do not drive or park over or near flammable materi-
als such as dry grass or fallen leaves, as they may
burn easily. The exhaust system is very hot while the
engine is running and right after the engine stops. This
could create a fire hazard." After driving through tall grass, mud, rocks, sand,
rivers, etc., check that there is no grass, bush, paper,
rags, stones, sand, etc. adhering to or trapped on the
underbody. Clear off any such matter from the under-
body. If the vehicle is used with these materials trapped or adhering to the underbody, a mechanical
breakdown or fire could occur. "
Secure all cargo carried inside the vehicle and make
certain that it is not piled higher than the seatbacks.
During sudden stops or jolts, unsecured cargo could
be thrown around in the vehicle and cause injury. Do
not pile heavy loads on the roof. Those loads raise the
vehicle’s center of gravity and make it more prone to
tip over." If you must rock the vehicle to free it from 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 pos-
sible traction, avoid spinning the wheels when trying to
free the vehicle.
When the road surface is extremely slippery, you can
obtain better traction by starting the vehicle with the
transmission in 2nd than 1st (both for MT and AT). " Never equip your vehicle with tires larger than those
specified in this manual. " Frequent driving of an AWD vehicle under hard-driv-
ing conditions such as rough roads or off roads will ne-
cessitate more frequent replacement of engine oil,
brake fluid and transmission oil than that specified in
the maintenance schedule described in the “Warranty
and Maintenance Booklet”.
Remember that damage done to your Subaru while

8-39
Driving tips
– CONTINUED –
tance is required because of the added weight and
length caused by attaching the trailer to your vehicle.
1) Left turn
2) Right turn
" Backing up with a trailer is difficult and takes prac-
tice. When backing up with a trailer, never accelerate
or steer rapidly. When turning back, grip the bottom of
the steering wheel with one hand and turn it to the left
for a left turn, and turn it to the right for a right turn." If the ABS warning light illuminates while the vehicle
is in motion, stop towing the trailer and have repairs
performed immediately by the nearest SUBARU deal-er. !
Driving on grades
" Before going down a steep hill, slow down and shift
into lower gear (if necessary, use 1st gear) in order to
utilize the engine braking effect and prevent overheat-
ing of your vehicle’s brakes. Do not make sudden
downshifts. " When driving uphill in hot weather, the air condition-
er may turn off automatically to protect the engine from
overheating. " When driving uphill in hot weather, pay attention to
the water temperature gauge pointer (for all vehicles)
and AT OIL TEMP warning light (for AT vehicles) since
the engine and transmission are relatively prone to
overheating under these conditions. If the water tem-
perature gauge pointer approaches the OVERHEAT
zone or the AT OIL TEMP warning light illuminates,
immediately switch off the air conditioner and stop the
vehicle at the nearest safe place. Refer to the “Engine
overheating” section in chapter 9, and “Warning and
indicator lights” section in chapter 3." If your vehicle has an automatic transmission, avoid
using the accelerator pedal to stay stationary on an
uphill slope instead of using the parking brake or foot
brake. That may cause the transmission fluid to over-
heat. Also, if your vehicle is equipped with an automat-
ic transmission, avoid driving with the gear selector le-
ver in “D” when towing a heavy trailer to prevent fluid
1 2
HS8023BB

9-20
In case of emergency
"
Use only the specified towing hook and tie-
down hook. Never use suspension parts or oth-
er body parts for towing or tie-down purposes." Never use the tie-down hook on the under-
side of the vehicle closest to the muffler for
towing purposes.
! Using a flat-bed truck
This is the best way to transport your vehicle. Use the
following procedures to ensure safe transportation. 1. Shift the selector lever into the “P” position for au-
tomatic transmission vehicles or “1st” for manual
transmission vehicles.
2. Pull up the parking brake lever firmly.
3. Secure the vehicle onto the carrier properly with
safety chains. Each safety chain should be equally
tightened and care must be taken not to pull the chains
so tightly that the suspension bottoms out.
If your vehicle has a front underspoiler and rear
underspoiler (both optional), be careful not to
scrape them when placing the vehicle on the
carrier and when removing the vehicle from the
carrier.
HG9023AA

9-21
In case of emergency
– CONTINUED –
!Towing with all wheels on the ground
1. Check the transmission and differential oil levels
and add oil to bring it to the upper level if necessary.
2. Release the parking brake and put the transmis-
sion in neutral.
3. The ignition switch should be in the “ACC” position
while the vehicle is being towed.
4. Take up slack in the towline slowly to prevent dam-
age to the vehicle.
" Never turn the ignition switch to the “LOCK”
position while the vehicle is being towed be- cause the steering wheel and the direction of
the wheels will be locked. "
Remember that the brake booster and power
steering do not function when the engine is not
running. Because the engine is turned off, it will
take greater effort to operate the brake pedal
and steering wheel.
" If transmission failure occurs, transport your
vehicle on a flat-bed truck. " Do not run the engine while being towed us-
ing this method. Transmission damage could
result if the vehicle is towed with the engine
running. " For vehicles with automatic transmission,
the traveling speed must be limited to less than
20 mph (30 km/h) and the traveling distance to
less than 31 miles (50 km). For greater speeds
and distances, transport your vehicle on a flat-
bed truck.
HG9024AA

11 - 1
11
Maintenance and service
Maintenance schedule ................................. 11-3
Maintenance precautions ............................ 11-3 Before checking or servicing in the engine compartment .................................................. 11-4
When you do checking or servicing in the engine compartment while the engine is
running ............................................................ 11-5
Engine hood .................................................. 11-5
Engine compartment overview ................... 11-8 2.5 liter model .................................................... 11-8
2.0 liter (Turbo) model ...................................... 11-9
2.5 liter (Turbo) model ...................................... 11-10
Engine oil ...................................................... 11-11 Checking the oil level ....................................... 11-11
Changing the oil and oil filter .......................... 11-12
Recommended grade and viscosity ................ 11-16
Recommended grade and viscosity under severe driving conditions .............................. 11-18
Synthetic oil ....................................................... 11-18
Cooling system ............................................. 11-18 Cooling fan, hose and connections ................ 11-19
Engine coolant .................................................. 11-19
Air cleaner element ...................................... 11-23 Replacing the air cleaner element ................... 11-23
Spark plugs ................................................... 11-26 Recommended spark plugs ............................. 11-27
Drive belts ..................................................... 11-27
Manual transmission oil ............................... 11-28 Checking the oil level ....................................... 11-28
Recommended grade and viscosity ................ 11-30 Automatic transmission fluid ...................... 11-31
Checking the fluid level .................................... 11-31
Recommended fluid ......................................... 11-32
Front differential gear oil (AT vehicles) ...... 11-33 Checking the oil level ....................................... 11-33
Recommended grade and viscosity ............... 11-33
Rear differential gear oil ............................... 11-34 Checking the gear oil level .............................. 11-34
Recommended grade and viscosity ............... 11-35
Power steering fluid ...................................... 11-36 Checking the fluid level .................................... 11-36
Recommended fluid ......................................... 11-37
Brake fluid ..................................................... 11-37 Checking the fluid level .................................... 11-37
Recommended brake fluid ............................... 11-38
Clutch fluid (MT vehicles) ............................ 11-38 Checking the fluid level .................................... 11-38
Recommended clutch fluid .............................. 11-39
Brake booster ................................................ 11-40
Brake pedal .................................................... 11-40 Checking the brake pedal free play ................ 11-40
Checking the brake pedal reserve distance ... 11-41
Clutch pedal (MT vehicles) ........................... 11-41 Checking the clutch function .......................... 11-41
Checking the clutch pedal free play ............... 11-42
Replacement of brake pad and lining ......... 11-42 Breaking-in of new brake pads and linings .... 11-43
Parking brake stroke .................................... 11-44
Tires and wheels ........................................... 11-44

11 - 8
Maintenance and service
Engine compartment overview !
2.5 liter model
12 345 67
8
9
10
11
12
13
UGB505BB
1) Manual transmission oil level
gauge (MT) (page 11-28) or Dif-
ferential gear oil level gauge
(AT) (page 11-33)
2) Air cleaner element (page 11- 23)
3) Clutch fluid reservoir (page 11- 38)
4) Automatic transmission fluid lev-
el gauge (page 11-31)
5) Brake fluid reservoir (page 11-
37)
6) Windshield washer tank (page 11-54)
7) Fuse box (page 11-60)
8) Battery (page 11-58)
9) Engine oil filler cap (page 11-11)
10) Engine coolant reservoir (page 11-19)
11) Radiator cap (page 11-19)
12) Engine oil level gauge (page 11- 11)
13) Power steering fluid reservoir
(page 11-36)