octane SUBARU LEGACY 2006 4.G Owners Manual

7-2 Starting and operating
Starting and operatingFuel
„Fuel requirements
T 2.5-liter non-turbo models
The 2.5-liter non-turbo engine is designed
to operate using unleaded gasoline with
an octane rating of 87 AKI or higher. T 2.5-liter turbo models and 3.0-liter models
The 2.5-liter turbo engine and 3.0-liter en-
gine are designed to operate using premi-
um unleaded gasoline with an octane rat-
ing of 91 AKI or higher. If premium unlead-
ed gasoline is not available, regular un-
leaded gasoline with an octane rating of
87 AKI or higher may be temporarily used.
For optimum engine performance and
driveability, it is required (for 2.5-liter turbo
models), and recommended (for 3.0-liter
models) that you use premium grade un-
leaded gasoline.
NOTE
Be sure to use premium unleaded gas- oline of 91 AKI or higher for a 2.5-liter
turbo engine model. If other gasoline
(lower than 91 AKI) is used, knocking,
reduced output and poor accelerator
response will result. T
Fuel octane rating
This octane rating is the average of the
Research Octane and Motor Octane num-
bers and is commonly referred to as the
Anti Knock Index (AKI).
Using a gasoline with a lower octane rat-
ing can cause persistent and heavy
knocking, which can damage the engine.
Do not be concerned if your vehicle some-
times knocks lightly when you drive up a
hill or when you accelerate. See your
dealer or a qualified service technician if
you use a fuel with the specified octane
rating and your vehicle knocks heavily or persistently. T Unleaded gasoline
The neck of the fuel f iller pipe is designed
to accept only an unleaded gasoline filler
nozzle. Under no circumstances should
leaded gasoline be used because it will damage the emission control system and
may impair driveability and fuel economy. T California fuel
If your vehicle was certified to California
Emission Standards as indicated on the underhood tune-up label,
it is designed to
optimize engine and emission control sys-
tem performance with gasoline that meets
the clean burning low-sulfur California
gasoline specifications. If you live in any
other state than Calif ornia, your vehicle
will operate on gasoline meeting Federal
specifications. Gasoline sold outside Cali-
fornia is permitted to have higher sulfur
levels, which may affect the performance
of your vehicle’s catalytic converter and
may produce a sulfur exhaust odor or
smell. SUBARU recomm ends that you try
a different brand of unleaded gasoline
having lower sulfur to determine if the
problem is fuel related before returning
your vehicle to an authorized dealer for
service. The CHECK ENGINE warning
light/Malfunction indicator lamp may also
turn on. If this occurs, return to your autho-
rized SUBARU dealer for diagnosis. If it is
determined that the condition is caused by
the type of fuel us ed, repairs may not be
covered by your warranty. T MMT
Some gasoline contains an octane-en-
hancing additive called MMT (Methylcy-
clopentadienyl Manganese Tricarbonyl). If
you use such fuels, your emission control
system performance may deteriorate and
the CHECK ENGINE warning light/Mal-
Use of a fuel which is low in quality
or use of an inappropriate fuel addi-
tive may cause engine damage.

Starting and operating 7-3
– CONTINUED –
function indicator lamp may turn on. If this
happens, return to your authorized
SUBARU Dealer for service. If it is deter-
mined that the condition is caused by the
type of fuel used, repairs may not be cov-
ered by your warranty. T
Gasoline for cleaner air
Your use of gasoline with detergent addi-
tives will help prevent deposits from form-
ing in your engine and fuel system. This
helps keep your engine in tune and your
emission control system working properly,
and is a way of doing your part for cleaner
air. If you continuously use a high quality
fuel with the proper detergent and other
additives, you should never need to add
any fuel system cleaning agents to your
fuel tank.
Many gasolines are now blended with ma-
terials called oxygenates. Use of these fu-
els can also help keep the air cleaner. Ox-
ygenated blend fuels, such as MTBE (Me- thyl Tertiary Butyl ether) or ethanol (ethyl
or grain alcohol) may be used in your ve-
hicle, but should contain no more than
15% MTBE or 10% ethanol for the proper
operation of your SUBARU.
In addition, some gasoline suppliers are
now producing reformulated gasolines,
which are designed to reduce vehicle
emissions. SUBARU approves the use of
reformulated gasoline.
If you are not sure what the fuel contains,
you should ask your service station oper-
ators if their gasolines contain detergents
and oxygenates and if they have been re-
formulated to reduce vehicle emissions.
As additional guidance, only use fuels
suited for your vehicle as explained in the
following. y
Fuel should be unleaded and have an
octane rating no lower than that specified
in this manual. y Methanol (methyl or wood alcohol) is
sometimes mixed with unleaded gasoline.
Methanol can be used in your vehicle ONLY if it does not exceed 5% of the fuel
mixture AND if it is accompanied by suffi-
cient quantities of the proper cosolvents
and corrosion inhibitors required to pre-
vent damage to the fuel system. Do not
use fuel containing methanol EXCEPT un-der these conditions.y
If undesirable driveability problems are
experienced and you suspect they may be
fuel related, try a di fferent brand of gaso-
line before seeking service at your
SUBARU dealer.y Fuel system damage or driveability
problems which result from the use of im-
proper fuel are not covered under the
SUBARU Limited Warranty.
Do not let fuel spill on the exterior
surfaces of the vehicle. Fuels con-
taining alcohol may cause paint
damage, which is not covered under
the SUBARU Limited Warranty.

GAS STATION REFERENCE
Fuel: T2.5-liter non-turbo models
Use only unleaded gasoline with an octane rating of 87 AKI or
higher. T 2.5-liter turbo models and 3.0-liter models
Use premium unleaded gasoline with an octane rating of 91 AKI or
higher. For temporary purposes if premium unleaded gasoline is
not available, you may use regular unleaded gasoline with an oc-
tane rating of 87 AKI or higher. For optimum engine performance
and driveability, it is required (for 2.5-liter turbo models), and rec-
ommended (for 3.0-liter models) that you use premium grade un-
leaded gasoline. „ Fuel octane rating
This octane rating is the average of the Research Octane and Mo- tor Octane numbers and is commonly referred to as the Anti Knock
Index (AKI). Refer to “Fuel
” section in this manual.
Fuel capacity:
16.9 US gal (64 liters, 14.1 Imp gal) Engine oil:
Use only API classification SM with the words “ENERGY CON-
SERVING” and the ILSAC certification mark (starburst mark) dis-
played on the container.
Engine oil capacity:
2.5-liter models: 4.2 US qt (4.0 liters, 3.5 Imp qt)
3.0-liter models: 5.8 US qt (5.5 liters, 4.8 Imp qt)
Cold tire pressure: Tire size P205/50R17 88V 215/45ZR17 P225/55R17 95V Wheel size 17 x 7 JJ
Pressure Front 33 psi (230 kPa, 2.3 kgf/cm 2
) 35 psi (240 kPa, 2.4 kgf/cm 2
) 32 psi (220 kPa, 2.2 kgf/cm 2
)
Rear 32 psi (220 kPa, 2.2 kgf/cm 2
) 33 psi (230 kPa, 2.3 kgf/cm 2
) 30 psi (210 kPa, 2.1 kgf/cm 2
)
Rear at trailer towing –
32 psi (220 kPa, 2.2 kgf/cm2
)
Temporary
spare tire Size T135/80R16 T135/70D17 T155/70D17
Pressure
60 psi (420 kPa, 4.2 kgf/cm2
)