Tires SUBARU WRX 2018 Workshop Manual

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北米Model "A1700BE-B" EDITED: 2017/ 10/ 11
Tire placardCheck the tire pressures when the tires are
cold. Use a pressure gauge to adjust the
tire pressures to the values shown on the
tire placard. The tire placard is located on
the door pillar on the driver’s side.
Driving even a short distance warms up
the tires and increases the tire pressures.
Also, the tire pressures are affected by the
outside temperature. It is best to check tire
pressure outdoors before driving the ve-
hicle.
When a tire becomes warm, the air inside it
expands, causing the tire pressure to
increase. Be careful not to mistakenly
release air from a warm tire to reduce its
pressure.
NOTE.The air pressure in a tire increases
by approximately 4.3 psi (30 kPa, 0.3
kgf/cm
2) when the tire becomes warm.
.The tires are considered cold when
you have parked the vehicle for at least
three hours or have driven less than
one mile (1.6 km).
WARNING
Do not let air out of warm tires to
adjust pressure. Doing so will result
in low tire pressure.
Incorrect tire pressures detract from con-
trollability and ride comfort, and they cause
the tires to wear abnormally..Correct tire pressure(tread worn
evenly)
Roadholding is good, and steering is
responsive. Rolling resistance is low, so
fuel consumption is also lower.
–CONTINUED–
Maintenance and service/Tires and wheels
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北米Model "A1700BE-B" EDITED: 2017/ 10/ 11
.Under inflated tire(tread worn on
shoulders)Rolling resistance is high, so fuel con-
sumption is also higher..Over inflated tire(tread worn in the
center)
Ride comfort is poor. Also, the tire magni-
fies the effects of road-surface bumps and
dips, possibly resulting in vehicle damage.
If the tire placard shows tire pressures for
the vehicle when fully loaded, adjust the
tire pressures to the values that match the
loading conditions.
WARNING
Driving at high speeds with exces-
sively low tire pressures can cause
the tires to deform severely and to
rapidly heat up. A sharp increase in
temperature could cause tread se-
paration, and destruction of the
tires. The resulting loss of vehiclecontrol could lead to an accident.
&Wheel balanceEach wheel was correctly balanced when
your vehicle was new, but the wheels will
become unbalanced as the tires become
worn during use. Wheel imbalance causes
the steering wheel to vibrate slightly at
certain vehicle speeds and detracts from
the vehicle’s straight-line stability. It can
also cause steering and suspension sys-
tem problems and abnormal tire wear. If
you suspect that the wheels are not
correctly balanced, have them checked
and adjusted by your SUBARU dealer.
Also have them adjusted after tire repairs
and after tire rotation.
CAUTION
Loss of correct wheel alignment
causes the tires to wear on one side
and reduces the vehicle’s running
stability. Contact your SUBARU
dealer if you notice abnormal tire
wear.
Maintenance and service/Tires and wheels
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北米Model "A1700BE-B" EDITED: 2017/ 10/ 11
NOTEThe suspension system is designed to
hold each wheel at a certain alignment
(relative to the other wheels and to the
road) for optimum straight-line stability
and cornering performance.&Wear indicators1) New tread
2) Worn tread
3) Tread wear indicatorEach tire incorporates a tread wear in-
dicator, which becomes visible when the
depth of the tread grooves decreases to
0.063 in (1.6 mm). Replace the tire when
the tread wear indicator appears as a solid
band across the tread.
WARNING
When a tire’s tread wear indicator
becomes visible, the tire is worn
beyond the acceptable limit and you
must replace it immediately. With a
tire in this condition, driving at high
speeds in wet weather can cause the
vehicle to hydroplane. The resulting
loss of vehicle control can lead to an
accident.NOTEFor safety, inspect tire tread regularly
and replace the tires before their tread
wear indicators become visible.
&Rotational direction of tiresExample of rotational direction marked on
the sidewall
1) FrontIf the tires have specific rotational direc-
tion, refer to the arrow marked on the side
wall.
The arrow should be pointing forward
when the wheels are fitted.
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Maintenance and service/Tires and wheels
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北米Model "A1700BE-B" EDITED: 2017/ 10/ 11
&Tire rotationVehicles equipped with 4 non-unidirec-
tional tires
1) Front
Vehicles equipped with unidirectional
tires
1) FrontTire wear varies from wheel to wheel.
Move the tires to the positions shown in the
illustration each time they are rotated. For
the tire rotation schedule, refer to the
“Warranty and Maintenance Booklet”.
Replace any damaged or unevenly worn
tires at the time of rotation. After tire
rotation, adjust the tires pressures and
make sure the wheel nuts are correctly
tightened.
After driving approximately 600 miles
(1,000 km), check the wheel nuts again
and retighten any nut that has become
loose.
&Tire replacementThe wheels and tires are important and
integral parts of your vehicle’s design; they
cannot be changed arbitrarily. The tires
fitted as standard equipment are optimally
matched to the characteristics of the
vehicle and were selected to give the best
possible combination of running perfor-
mance, ride comfort, and service life. It is
essential for every tire to have a size and
construction matching those shown on the
tire placard and to have a speed symbol
and load index matching those shown on
the tire placard.
Using tires of a non-specified size detracts
from controllability, ride comfort, braking
performance, speedometer accuracy and
odometer accuracy. It also creates incor-
rect body-to-tire clearances and inappro-
priately changes the vehicle’s ground
clearance.
All four tires must be the same in terms of
manufacturer, brand (tread pattern), con-
struction, and size. You are advised to
replace the tires with new ones that are
identical to those fitted as standard equip-
ment.
For safe vehicle operation, SUBARU
recommends replacing all four tires at the
same time.
Maintenance and service/Tires and wheels
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北米Model "A1700BE-B" EDITED: 2017/ 10/ 11
WARNING
.When replacing or installing
tire(s), all four tires must be the
same for the following items.
(a) Size
(b) Circumference
(c) Speed symbol
(d) Load index
(e) Construction
(f) Manufacturer
(g) Brand (tread pattern)
(h) Degrees of wear
For items (a) to (d), you must
obey the specification that is
printed on the tire placard. The
tire placard is located on the
driver’s door pillar.
If all four tires are not the same in
items (a) to (h), there is a possi-
bility that it may lead to serious
mechanical damage to the drive
train of your car and affect the
following factors.
—Ride
—Handling
—Braking—Speedometer/Odometer
calibration
—Clearance between the body
and the tires
It also may be dangerous and
lead to loss of vehicle control,
and it can lead to an accident.
.Use only radial tires. Do not use
radial tires together with belted
bias tires and/or bias-ply tires.
Doing so can dangerously re-
duce controllability, resulting in
an accident.
&Wheel replacementWhen replacing wheels due, for example,
to damage, make sure the replacement
wheels match the specifications of the
wheels that are fitted as standard equip-
ment. Replacement wheels are available
from SUBARU dealers.
WARNING
Use only those wheels that are
specified for your vehicle. Wheels
not meeting specifications could
interfere with brake caliper opera-
tion and may cause the tires to rub
against the wheel well housing dur-ing turns. The resulting loss of
vehicle control could lead to an
accident.
NOTEWhen any of the wheels are removed
and replaced for tire rotation or to
change a flat tire, always check the
tightness of the wheel nuts after driving
approximately 600 miles (1,000 km). If
any nut is loose, tighten it to the
specified torque.
Maintenance and service/Tires and wheels
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北米Model "A1700BE-B" EDITED: 2017/ 10/ 11
Specifications........................................................12-2
Dimensions...........................................................12-2
Engine..................................................................12-3
Fuel......................................................................12-3
Engine oil.............................................................12-4
Manual transmission, front differential and rear
differential gear oil..............................................12-6
Fluids...................................................................12-7
Engine coolant......................................................12-7
Electrical system..................................................12-8Tires.....................................................................12-8
Temporary spare tires...........................................12-9
Brake disc............................................................12-9
Fuses and circuits..............................................12-10
Fuse panel located in the passenger
compartment...................................................12-10
Fuse panel located in the engine compartment ... 12-12
Bulb chart............................................................12-14
Vehicle identification..........................................12-16
Specifications
12

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北米Model "A1700BE-B" EDITED: 2017/ 10/ 11
&Electrical systemAlternatorSTI 12V-110A
Except STI 12V-130A
Spark plugsTYPE RA ILFR7H (NGK)
STI except TYPE RA SILFR6A (NGK)
Except STIILKAR8H6 (NGK)&TiresTire sizeSTI—245/40R18 97W 245/35R19 89W
Except STI 235/45R17 94W 245/40R18 97W—
Wheel size
1768J 1868 1/2J 1968 1/2J
Pressure Front
33 psi (230 kPa, 2.3 kgf/cm
2)
Rear
32 psi (220 kPa, 2.2 kgf/cm2)
Wheel nut tightening torque
89 lbf·ft (120 N·m, 12 kgf·m)*1
*1: This torque is equivalent to applying approximately 88 to 110 lbf (40 to 50 kgf) at the end of the wheel nut wrench. If you have tightened the wheel nuts
by yourself, have the tightening torque checked at the nearest automotive service facility as soon as possible. For the wheel nut tightening procedure,
refer to“
Changing a flat tire”F9-5.Specifications/Specifications
12-8

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北米Model "A1700BE-B" EDITED: 2017/ 10/ 11
&Temporary spare tiresTemporary spare tire size T145/70D17 T135/70D18 205/50R17 205/45R18
Temporary spare tire inflation pressure
(recommended cold tire inflation pressure)60 psi (420 kPa, 4.2 kgf/cm
2) 33 psi (230 kPa, 2.3 kgf/cm
2) 38 psi (260 kPa, 2.6 kgf/cm
2)
Wheel nut tightening torque
89 lbf·ft (120 N·m, 12 kgf·m)*
1*2
*1: This torque is equivalent to applying approximately 88 to 110 lbf (40 to 50 kgf) at the end of the wheel nut wrench. If you have tightened the wheel nuts
by yourself, have the tightening torque checked at the nearest automotive service facility as soon as possible.
*2: For the wheel nut tightening procedure, refer to“
Changing a flat tire”F9-5.
&Brake discIf you need information on the usage limit value of brake discs and the method for measuring them, consult your SUBARU dealer.
Specifications/Specifications
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北米Model "A1700BE-B" EDITED: 2017/ 10/ 11
For U.S.A...............................................................13-2
Tire information.....................................................13-2
Tire labeling..........................................................13-2
Recommended tire inflation pressure....................13-4
Glossary of tire terminology..................................13-5
Tire care–maintenance and safety practices......13-10
Vehicle load limit–how to determine..................13-10
Determining compatibility of tire and vehicle
load capacities..................................................13-13Adverse safety consequences of overloading
on handling and stopping and on tires.............13-14
Steps for Determining Correct Load Limit ...........13-14
Uniform tire quality gradingstandards.............13-15
Treadwear...........................................................13-15
Traction AA, A, B, C............................................13-15
Temperature A, B, C...........................................13-15
Reporting safety defects(U.S.A.)......................13-16
Consumer information and Reporting safety defects
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北米Model "A1700BE-B" EDITED: 2017/ 10/ 11
Example:(6) Load Index: A numerical code
which specifies the maximum load
a tire can carry at the speed
indicated by its speed symbol, at
maximum inflation pressure.
For example,“90”means 1,323 lbs
(600 kg),“89”means 1,278 lbs (580
kg).
WARNING
Load indices apply only to the
tire, not to the vehicle. Putting
a load rated tire on any vehicle
does not mean the vehicle can
be loaded up to the tire’s rated
load.
(7) Speed Rating: An alphabetical
system describing a tire’s capability
to travel at established and prede-
termined speeds.
For example,“V”means 149 mph
(240 km/h)
WARNING
.
Speed ratings apply only to
the tire, not to the vehicle.
Putting a speed rated tire on
any vehicle does not mean
the vehicle can be operated
at the tire’s rated speed.
.
The speed rating is void if
the tires are worn out, da-
maged, repaired, retreaded,
or otherwise altered from
their original condition. If
tires are repaired, re-
treaded, or otherwise al-
tered, they may not be sui-
table for original equipment
tire designed loads and
speeds.
!Tire Identification Number (TIN)Tire Identification Number (TIN) is
marked on the intended outboard
sidewall. The TIN is composed of
four groups. Here is a brief review of
the TIN with a breakdown of its
individual elements.
(1) Manufacturer’s Identification
Mark
(2) Tire Size
(3) Tire Type Code
(4) Date of Manufacture
The first two figures identify the
week, starting with“01”to represent
the first full week of the calendar
year; the second two figures repre-
sent the year. For example, 0101
means the 1st week of 2001.!Other markingsThe following makings are also
placed on the sidewall.
!Maximum permissible infla-
tion pressure
The maximum cold inflation pres-
sure to which this tire may be
inflated. For example,“300 kPa
(44 PSI) MAX. PRESS”
–CONTINUED–
Consumer information and Reporting safety defects/Tire information
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