oil viscosity SUBARU IMPREZA WRX 2004 2.G Owners Manual

8-11
Driving tips
– CONTINUED –
operating it off-road and not using common sense pre-
cautions such as those listed above is not eligible for
warranty coverage."Wash the vehicle’s underbody after off-road driving.
Suspension components are particularly prone to dirt
buildup, so they need to be washed thoroughly.Winter driving ! Operation during cold weather
Carry some emergency equipment, such as tire
chains, a window scraper, a bag of sand, flares, a
small shovel, and jumper cables.
Check the battery and cables. Cold temperatures re-
duce battery capacity. The battery must be in good
condition to provide enough power for cold winter starts.
Use an engine oil of proper grade and viscosity for
cold weather. Heavy summer oil will cause harder
UG8030AA

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 - 1 2
Maintenance and service
2.5-liter and 2.0-liter turbo models
1) Notch
2) Upper level
3) Lower level
4. Pull out the dipstick 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.
" Use only engine oil with the recommended
grade and viscosity. " Be careful not to spill engine oil when adding
it. If oil touches the exhaust pipe, it may cause
a bad smell, smoke, and/or a fire.
If you check the oil level just after stopping the engine,
wait a few minutes for the oil to drain back into the oil
pan before checking the level.
Just after driving or while the engine is warm, the en-
gine oil level reading may be in a range between the
upper level and the notch mark. This is caused by ther-
mal expansion of the engine oil.
To prevent overfilling the engine oil, do not add any
additional oil above the upper level when the engine iscold. ! Changing the oil and oil filter
Change the oil and oil filter according to the mainte-
nance schedule in the “Warranty and Maintenance Booklet”.
The engine oil and oil filter must be changed more fre-
quently than listed in the maintenance schedule when
driving on dusty roads, when short trips are frequently
made, or when driving in extremely cold whether.
1. Warm up the engine by letting the engine idle for
about 10 minutes to ease draining the engine oil.
2. Park the vehicle on a level surface and stop the en-
gine.
1 2
3
UGB082BB

11 - 1 6
Maintenance and service
again and if necessary, add more engine oil.
Be careful not to spill engine oil when adding it.
If oil touches the exhaust pipe, it may cause a
bad smell, smoke, and/or a fire.
! Recommended grade and viscosity
Oil grade:
ILSAC GF-3, which can be identified with the new
API certification mark (Starburst mark)
or API classification SL with the words “ENERGY
CONSERVING” (if you cannot obtain the oil with
SL grade, you may use SJ grade “ENERGY CON-
SERVING” oil).
These recommended oil grades can be identified by
looking for either or both of the following marks dis-
played on the oil container. API Service label
1) Indicates the oil quality by API designations
2) Indicates the SAE oil viscosity grade
3) Indicates that the oil has fuel saving capabilities
APISERVICESL
ENERGYCONSERVING
SAE
5W
30
1
2
3
HSB022BB

11 -1 7
Maintenance and service
– CONTINUED –
New API Certification Mark (Starburst Mark)
In choosing an oil, you want the proper quality and vis-
cosity, as well as one that will add to fuel economy.
The following table lists the recommended viscosities
and applicable temperatures.
When adding oil, different brands may be used togeth-
er as long as they are the same API classification and
SAE viscosity as those recommended by SUBARU. SAE viscosity number and applicable temperature
*: 5W-30 is preferred.
Engine oil viscosity (thickness) affects fuel economy.
Oils of lower viscosity provide better fuel economy.
However, in hot weather, oil of higher viscosity is re-
quired to properly lubricate the engine.
Use only engine oil with the recommended
grade and viscosity.
AMERICANPETROLEUMINSTITUTE
CERTIFIED
HSB023AA
5W-30*
10W-30, 10W-40
-30 -20 -10 0 10 20 30 40
-20
06 0
20 80 100 40
UGB084BA

11 - 1 8
Maintenance and service
!
Recommended grade and viscosity
under severe driving conditions
If the vehicle is used in desert areas, in areas with very
high temperatures, or used for heavy-duty applica-
tions such as towing a trailer, use of oil with the follow-
ing grade and viscosities is recommended.
API classification SL (or SJ):
SAE viscosity No.: 30, 40, 10W-50, 20W-40, 20W-50
! Synthetic oil
You can use synthetic engine oil that meets the same
requirements given for conventional engine oil. When
using synthetic oil, you must use oil of the same clas-
sification, viscosity and grade shown in this owner’s
manual, and must follow the oil and filter changing in-
tervals shown in the maintenance schedule.
Cooling system
Never attempt to remove the radiator cap until
the engine has been shut off and has cooled
down completely. Since the coolant is under
pressure, you may suffer serious burns from a
spray of boiling hot coolant when the cap is re-
moved.
" The cooling system has been filled at the fac-
tory with a high quality, corrosion-inhibiting,
year-around coolant which provides protection
against freezing down to –33 °F (–36 °C). For
adding, use genuine SUBARU coolant or an
equivalent: a mixture of 50% soft water and 50%
ethylene-glycol basis coolant. Use of improper
coolants may result in corrosion in the cooling
system. It is important to maintain protection
against freezing and corrosion, even if freezing
temperatures are not expected. Never mix dif-
ferent kinds of coolant. " Do not splash the engine coolant over paint-

11 - 3 0
Maintenance and service
1) Upper level
2) Lower level
3. Pull out the dipstick again and check the oil level on
it. If it is below the lower level, add oil through the dip-
stick hole to bring the level up to the upper level. ! Recommended grade and viscosity
Each oil manufacturer has its own base oils and addi-
tives. Never use different brands together.
Oil grade:
API classification GL-5 SAE viscosity No. and Applicable Temperature
L
F
F
L1
2 1
2
USB526BB
-30 -20 -10 0 10 20 30 40-20 0 60 20
80W
75W/90 80 100
40
85W 90
HSB036BA

11 -3 3
Maintenance and service
– CONTINUED –
Front differential gear oil (AT vehi-
cles) !Checking the oil level
1) Yellow handle
1. Park the vehicle on a level surface and stop the en-
gine.
2. Pull out the dipstick, wipe it clean, and insert it
again. 1) Upper level
2) Lower level
3. Pull out the dipstick 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. ! Recommended grade and viscosity
Each oil manufacturer has its own base oils and addi-
tives. Never use different brands together.
Oil grade:
API classification GL-5
HGB056FB
1
L F
1 2
HSB040BB

11 - 3 4
Maintenance and service
SAE viscosity No. and Applicable Temperature
Rear differential gear oil !
Checking the gear oil level
Your vehicle may be equipped with a rear differential
protector. The differential protector provides protec-
tion to the rear differential assembly during off-road
use. Removal of the rear differential protector is not re-
quired when checking the oil level.
1) Filler plug
2) Drain plug
-30
-20 20 40 60 90
85W
80W
80W/90 80 100
0
-20 -10 10 20 30 40
0
HSB041AA
2 1HSB042BB

11 -3 5
Maintenance and service
– CONTINUED –
1) Filler hole
2) Drain hole
3) Oil level
Remove the plug from the filler hole and check the oil
level. The oil level should be kept even with the bottom
of the filler hole. If the oil level is below the bottom
edge of the hole, add oil through the filler hole to raisethe level.
If the vehicle requires frequent refilling, there
may be an oil leak. If you suspect a problem,
have the vehicle checked at your SUBARU deal-
er.
! Recommended grade and viscosity
Each oil manufacturer has its own base oils and addi-
tives. Never use different brands together.
Oil grade:
API classification GL-5
SAE viscosity No. and Applicable Temperature
3 1
2
HSB043BB-30 -20 -10 0 10 20 30 40-20 0 60 20
80W
75W/90 80 100
40
85W 90
HSB036BA