254 Car careAutomatic tire pressure
monitoring3The pressure monitoring system consists of
a sensor in each wheel, a detector in three
wheel housings and a receiver. The sensors
are located inside the wheels directly adja-
cent to the air valves.Each tire, including the spare (if provided),
should be checked monthly when cold and
inflated to the inflation pressure recom-
mended by the vehicle manufacturer on the
vehicle placard or tire inflation pressure
label. (If your vehicle has tires of a different
size than the size indicated on the vehicle
placard or tire inflation pressure label, you
should consult the appropriate section of
this owner’s manual to determine the proper
tire inflation pressure, see page 306.) When
the low tire pressure telltale is illuminated,
one or more of your tires is significantly
underinflated.
You should stop and check your tires as
soon as possible, and inflate them to the
proper pressure. Driving on a significantly
under-inflated tire causes the tire to over-
heat and can lead to tire failure.
WARNING
The system is intended to aid the driver.
The driver is always ultimately responsi-
ble for ensuring that the tire pressure is
correct.
For optimum safety, economy and
comfort, check the tires regularly, even if
the automatic tire pressure monitoring
system has not issued an alarm
NOTICEGreat care must be taken when changing
tires so as not to damage the sensors that
are integrated in the valves.
Remove the rear side first.
Start removing the tire at a point oppo-
site the valve.
Do not allow the tire removal equip-
ment to come closer than approx.
10 cm to the valve.
Start and finish fitting approx. 4 in.
(10 cm) from the valve.
Do not inflate the tire to above
700 kPa/100 psi.
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255 Car care
Under-inflation also reduces fuel efficiency
and tire tread life, and may affect the vehi-
cle’s handling and stopping ability.
Your vehicle has also been equipped with a
TPMS malfunction telltale to indicate when
the system is not operating properly. When
the malfunction telltale is illuminated, the
system may not be able to detect or signal
low tire pressure as intended. TPMS mal-
functions may occur for a variety of reasons,
including the installation of incompatible
replacement tires on the vehicle. Always
check the TPMS malfunction telltale after
replacing one or more tires on your vehicle
to ensure that the replacement tires are
compatible with the TPMS.
Tire pressure information is sent wirelessly
to the receiver.
The system checks the tire pressure when
the car is travelling over 18 mph (30 km/h).
The system is “self-learning”, which means
that the position of the wheels can be
changed without requiring adjustments to
the monitoring system. The spare wheel
does not have a sensor.
The sensor batteries have an average life of
10 years. The batteries cannot be changed
but require the sensor units to be replaced.
The system does not warn if a tire is overin-
flated.If the tire pressure drops
If the tire pressure drops 25% or more below
highest recommended pressure (see tire
pressure label on page 267), the SID will
issue a warning as to which tire is affected.
Adjust the tire pressure as soon as possible.If the vehicle is equipped with a different
wheel size than those fitted as standard and
therefore should use a different recom-
mended highest tire pressure the owner
shall contact a workshop to have the system
recalibrated. We recommend that you
contact a Saab dealer. Low tire pressure,
front left.
Make a safe stop.
Valve without sensor
Valve with sensor
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259 Car care
Flat spottingAll tires get hot, especially on long journeys
or when the car is driven hard. After the car
has been parked with hot tires and the tires
have cooled down, a flat spot can form in the
tire, where it is in contact with the ground.
The same can occur if the car has not been
moved for a long time.
Flat spots can cause vibration that can be
felt through the steering wheel, similar to
that experienced when the wheels need bal-
ancing.
Flat spots of this type disappear once the
tires get hot again, usually after 10–15 miles
(20–25 km) of driving at cruising speed. If
the outdoor temperature is low it takes a
longer distance.
When It Is Time for New TiresOne way to tell when it’s time for new tires is
to check the treadwear indicators, which will
appear when your tires have only 1/16 inch
(1.6 mm) or less of tread remaining.
You need a new tire if any of the following
statements are true:
You can see the indicators at three or
more places around the tire.
You can see cord or fabric showing
through the tire’s rubber.
The tread or sidewall is cracked, cut or
snagged deep enough to show cord or
fabric.
The tire has a bump, bulge or split.
The tire has a puncture, cut or other
damage that can’t be repaired well
because of the size or location of the
damage.
Treadwear indicatorsThe tires incorporate wear indicators in the
form of smooth, treadless strips across the
width, which become visible when only
2/32" (1.6 mm) of tread remains. As soon as
the indicators become visible, new tires
should be fitted without delay.
Make sure you are familiar with the legal
limit for minimum tread depth in your
country and also any regulations gov-
erning the use of winter (snow) tires.Treadwear indicator
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260 Car careBuying New TiresTo find out what kind and size of tires you
need, look at the Tire-Loading Information
label.
If you wish to fit other tires or wheels than
those supplied with the car, consult your
Saab dealer first as to the possibilities
available.
Wheels/tires combinations that are not
approved by Saab can negatively affect the
car’s directional stability, steering and brak-
ing in both wet and dry conditions.The wheels and tires have been carefully
matched to the characteristics of the car and
play a key role in its outstanding roadhold-
ing and handling.
Do not take it for granted that a wheel/tire
combination will work in the best possible
way, just because it can be fitted to the car.
To ensure that the speedometer is as accu-
rate as possible it should be reprogrammed
if wheels of a different dimension are fitted.
Contact a Saab dealer.
Because of front wheel drive, the front tires
tend to wear faster than the rear ones. New
tires should always be fitted in pairs, so that
tires on the same axle have the same
amount of tread.
Store wheels lying flat or hanging – never
standing upright.
NOTICEAlways consult your Saab dealer before
changing the car’s wheels or tires on your
Saab.
Wide wheels and tires with side walls that
are too low can:
be damaged in potholes, etc.
cause springs, shock absorbers and
wheel bearings and body mountings
to be overloaded.
affect the function of the Electronic
Stability Program (ESP).
The speed and load limits of the tires
must not be exceeded; see page 266.
Wheels larger than 17" must not be fitted
on the Saab 9-3 for reasons above. The
permissible offset is 1.61 inch (41 mm).
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261 Car care
Uniform Tire Quality GradingQuality grades can be found where applica-
ble on the tire sidewall between tread shoul-
der and maximum section width. For exam-
ple:
Treadwear 200 Traction AA Temperature
A
The following information relates to the
system developed by the United States
National Highway Traffic Safety Administra-
tion, which grades tires by treadwear, trac-
tion and temperature performance. (This
applies only to vehicles sold in the United
States.) The grades are molded on the side-
walls of most passenger car tires. The Uni-
form Tire Quality Grading system does not
apply to deep tread, winter-type snow tires,
space-saver or temporary use spare tires,
tires with nominal rim diameters of 10 to 12
inches (25 to 30 cm), or to some limited-pro-
duction tires.
While the tires available on General Motors
passenger cars and light trucks may vary
with respect to these grades, they must also
conform to federal safety requirements and
additional General Motors Tire Perfor-
mance Criteria (TPC) standards.Treadwear
The treadwear grade is a comparative
rating based on the wear rate of the tire
when tested under controlled conditions on
a specified government test course. For
example, a tire graded 150 would wear one
and a half (1.5) times as well on the govern-
ment course as a tire graded 100. The rela-
tive performance of tires depends upon the
actual conditions of their use, however, and
may depart significantly from the norm due
to variations in driving habits, service prac-
tices and differences in road characteristics
and climate.
Traction – AA, A, B, C
The traction grades, from highest to lowest,
are AA, A, B, and C. Those grades repre-
sent the tire’s ability to stop on wet pave-
ment as measured under controlled condi-
tions on specified government test surfaces
of asphalt and concrete. A tire marked C
may have poor traction performance. Warn-
ing: The traction grade assigned to this tire
is based on straight-ahead braking traction
tests, and does not include acceleration,
cornering, hydroplaning, or peak traction
characteristics.
WARNING
Mixing tires could cause you to lose
control while driving. If you mix tires of
different sizes or types (radial and bias-
belted tires), the vehicle may not handle
properly, and you could have a crash.
Using tires of different sizes may also
cause damage to your vehicle. Be sure to
use the same size and type tires on all
wheels. It’s all right to drive with your
compact spare temporarily, it was devel-
oped for use on your vehicle. See
“Compact spare” on page 270.
WARNING
If you use bias-ply tires on your vehicle,
the wheel rim flanges could develop
cracks after many miles of driving. A tire
and/or wheel could fail suddenly, causing
a crash. Use only radial-ply tires with the
wheels on your vehicle.93U S M 06.book Page 261 Friday, February 18, 2005 1:15 PM
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263 Car care
Notice:
The wrong wheel can also cause
problems with bearing life, brake cool-
ing, speedometer or odometer calibra-
tion, headlamp aim, bumper height, vehi-
cle ground clearance and tire or tire
chain clearance to the body and chassis.
See “Changing a tire” on page 273.Used Replacement Wheels
Tire Chains
WARNING
When fitting just one new pair of tires,
these should be fitted to the rear wheels,
as these are more critical to the direc-
tional stability of the car (e.g. on braking
or in a skid). The existing rear wheels
should therefore be moved to the front.
WARNING
Putting a used wheel on your vehicle is
dangerous. You can’t know how it’s been
used or how far it’s been driven. It could
fail suddenly and cause a crash. If you
have to replace a wheel, use a new GM
original equipment wheel.
WARNING
If your vehicle has 235/45 R17 size tires,
don’t use tire chains, there’s not enough
clearance.
Tire chains used on a vehicle without the
proper amount of clearance can cause
damage to the brakes, suspension or
other vehicle parts. The area damaged by
the tire chains could cause you to lose
control of your vehicle and you or others
may be injured in a crash.
Use another type of traction device only if
its manufacturer recommends it for use
on your vehicle and tire size combination
and road conditions. Follow that manu-
facturer’s instructions. To help avoid
damage to your vehicle, drive slowly,
readjust or remove the device if it’s
contacting your vehicle, and don’t spin
your wheels.
If you do find traction devices that will fit,
install them on the front tires.
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264 Car careNotice:
If your vehicle does not have
235/45R17 size tires, use tire chains only
where legal and only when you must.
Contact your Saab dealer regarding suit-
able snow chains. Install them on the
front tires and tighten them as tightly as
possible with the ends securely
fastened. Drive slowly and follow the
chain manufacturer’s instructions. If you
can hear the chains contacting your
vehicle, stop and retighten them. If the
contact continues, slow down until it
stops. Driving too fast or spinning the
wheels with chains on will damage your
vehicle.
If a Tire Goes FlatIt’s unusual for a tire to “blowout” while
you’re driving, especially if you maintain
your tires properly. If air goes out of a tire,
it’s much more likely to leak out slowly. But
if you should ever have a “blowout”, here are
a few tips about what to expect and what to
do:
If a front tire fails, the flat tire will create a
drag that pulls the vehicle toward that side.
Take your foot off the accelerator pedal and
grip the steering wheel firmly. Steer to main-
tain lane position, and then gently brake to
a stop well out of the traffic lane.
A rear blowout, particularly on a curve, acts
much like a skid and may require the same
correction you’d use in a skid. In any rear
blowout, remove your foot from the acceler-
ator pedal. Get the vehicle under control by
steering the way you want the vehicle to go.
It may be very bumpy and noisy, but you can
still steer. Gently brake to a stop – well off
the road if possible.
If a tire goes flat, the next part shows how to
use your jacking equipment to change a flat
tire safely.
Tire Sidewall LabelingUseful information about a tire is molded
into it´s sidewall.
Tire size: The tire size ia a combination of
letters and numbers used to define a partic-
ular tire´s width, height, aspect ratio, con-
struction type and service description.
Department of Transportation (DOT):
The Department of Transportation (DOT)
code indicates that the tire is in compliance
with the U.S. Department of Transportation
Motor Vehicle Safety standards.
Tire Identification Number (TIN): The let-
ters and numbers following DOT code are
the Tire Identification Number (TIN). The
TIN shows the manufacturer and plant
code, tire size, and date the tire was manu-
factured. The TIN is molded onto both sides
of the tire.
Tire Ply Material: The type of cord and
number of plies in the sidewall and under
the tread.
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265 Car care
Uniform Tire Quality Grading (UTQG):
Tire manufacturers are required to grade
tires based on the performance factors:
treadwear, traction and temperature resis-
tance. For more information see “Uniform
Tire Quality Grading” on page 261.
Maximum Cold Inflation Load Limit: Max-
imum load that can be carried and the max-
imum pressure needed to support that load.
For information on recommended tire pres-
sure see “Recommended lowest tire pres-
sure, cold tires” on page 306 and “Loading
Your Vehicle” on page 267.
Tire SizeThe following illustration shows an example
of a typical passenger car tire size.
Tire Width: The three-digit number indi-
cates the tire section width in millimeters
from sidewall to sidewall.Aspect ratio: A two-digit number that indi-
cates the tire height-to-width measure-
ments. For example, if the tire size aspect
ratio is “55”, as shown in item “C” of the illus-
tration, it would mean that the tire´s sidewall
is 55% as high as it is wide.
Belt Rating: A letter code is used to indicate
the type of ply construction in the tire. The
letter “R” means radial ply construction; the
letter “D” means diagonal or bias ply con-
struction; and the letter “B” means belted-
bias ply construction.
Rim Diameter: Diameter of the wheel in
inches.
Load range: The load range represents the
load carry capacity a tire is certified to carry.
Speed Rating: The maximum speed that a
tire is certified to carry a load. Speed ratings
range from “A” to “Z”. 215/55 R 16 93 H
||||||
abcdef
aTire Width
b Aspect Ratio
c Belt Rating
d Rim diameter
e Load range
f Speed rating
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