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Tires
Your new vehicle comes with high-quality tires
made by a leading tire manufacturer. If you ever
have questions about your tire warranty and where
to obtain service, see your Saab Warranty
booklet for details. For additional information refer
to the tire manufacturer’s booklet included with
your vehicle.
{CAUTION:
Poorly maintained and improperly
used tires are dangerous.
Overloading your tires can cause
overheating as a result of too much
friction. You could have an air-out and
a serious accident. SeeLoading Your
Vehicle on page 296.
CAUTION: (Continued)
CAUTION: (Continued)
Underin ated tires pose the same
danger as overloaded tires. The
resulting accident could cause serious
injury. Check all tires frequently to
maintain the recommended pressure.
Tire pressure should be checked when
your tires are cold. SeeInflation - Tire
Pressure on page 388.
Overin ated tires are more likely to be
cut, punctured, or broken by a sudden
impact — such as when you hit a
pothole. Keep tires at the
recommended pressure.
Worn, old tires can cause accidents.
If your tread is badly worn, or if
your tires have been damaged,
replace them.
SeeHigh-Speed Operation on page 390for
in ation pressure adjustment for high
speed driving.
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Tire Sidewall Labeling
Useful information about a tire is molded into the
sidewall. The following illustrations are examples
of a typical P-Metric and a LT-Metric tire sidewall.(A) Tire Size:The tire size code is a combination
of letters and numbers used to de ne a particular
tire’s width, height, aspect ratio, construction
type, and service description. See the “Tire Size”
illustration later in this section for more detail.
(B) TPC Spec (Tire Performance Criteria
Speci cation):Original equipment tires designed
to GM’s speci c tire performance criteria have
a TPC speci cation code molded onto the sidewall.
GM’s TPC speci cations meet or exceed all
federal safety guidelines.
(C) DOT (Department of Transportation):
The Department of Transportation (DOT) code
indicates that the tire is in compliance with the U.S.
Department of Transportation Motor Vehicle Safety
Standards.
(D) Tire Identi cation Number (TIN):The letters
and numbers following DOT code are the Tire
Identi cation Number (TIN). The TIN shows
the manufacturer and plant code, tire size, and
date the tire was manufactured. The TIN is molded
onto both sides of the tire, although only one side
may have the date of manufacture.
Passenger (P-Metric) Tire
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(E) Tire Ply Material:The type of cord and
number of plies in the sidewall and under
the tread.
(F) Uniform Tire Quality Grading (UTQG):
Tire manufacturers are required to grade
tires based on three performance factors:
treadwear, traction, and temperature resistance.
For more information, seeUniform Tire Quality
Grading on page 400.
(G) Maximum Cold In ation Load Limit:
Maximum load that can be carried and the
maximum pressure needed to support that load.
For information on recommended tire pressure
seeIn ation - Tire Pressure on page 388
andLoading Your Vehicle on page 296.
(A) Tire Size:The tire size code is a combination
of letters and numbers used to de ne a particular
tire’s width, height, aspect ratio, construction
type, and service description. See the “Tire Size”
illustration later in this section for more detail.
Light Truck (LT-Metric) Tire
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(B) TPC Spec (Tire Performance Criteria
Speci cation):Original equipment tires designed
to GM’s speci c tire performance criteria have
a TPC speci cation code molded onto the sidewall.
GM’s TPC speci cations meet or exceed all
federal safety guidelines.
(C) Dual Tire Maximum Load:Maximum load
that can be carried and the maximum pressure
needed to support that load when used in a dual
con guration. For information on recommended
tire pressure seeIn ation - Tire Pressure on
page 388andLoading Your Vehicle on page 296.
(D) DOT (Department of Transportation):
The Department of Transportation (DOT) code
indicates that the tire is in compliance with the
U.S. Department of Transportation Motor Vehicle
Safety Standards.(E) Tire Identi cation Number (TIN):The letters
and numbers following DOT code are the Tire
Identi cation Number (TIN). The TIN shows
the manufacturer and plant code, tire size, and
date the tire was manufactured. The TIN is
molded onto both sides of the tire, although only
one side may have the date of manufacture.
(F) Tire Ply Material:The type of cord and
number of plies in the sidewall and under
the tread.
(G) Single Tire Maximum Load:Maximum load
that can be carried and the maximum pressure
needed to support that load when used as a
single. For information on recommended
tire pressure seeIn ation - Tire Pressure on
page 388andLoading Your Vehicle on page 296.
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Radial Ply Tire:A pneumatic tire in which the
ply cords that extend to the beads are laid
at 90 degrees to the centerline of the tread.
Rim:A metal support for a tire and upon which
the tire beads are seated.
Sidewall:The portion of a tire between the tread
and the bead.
Speed Rating:An alphanumeric code assigned
to a tire indicating the maximum speed at
which a tire can operate.
Traction:The friction between the tire and the
road surface. The amount of grip provided.
Tread:The portion of a tire that comes into
contact with the road.
Treadwear Indicators:Narrow bands, sometimes
called wear bars, that show across the tread of a
tire when only 1/16 inch (1.6 mm) of tread remains.
SeeWhen It Is Time for New Tires on page 397.UTQGS (Uniform Tire Quality Grading
Standards):A tire information system that
provides consumers with ratings for a tire’s
traction, temperature, and treadwear. Ratings
are determined by tire manufacturers using
government testing procedures. The ratings are
molded into the sidewall of the tire. SeeUniform
Tire Quality Grading on page 400.
Vehicle Capacity Weight:The number of
designated seating positions multiplied by
150 lbs (68 kg) plus the rated cargo load.
SeeLoading Your Vehicle on page 296.
Vehicle Maximum Load on the Tire:Load on
an individual tire due to curb weight, accessory
weight, occupant weight, and cargo weight.
Vehicle Placard:A label permanently attached
to a vehicle showing the vehicle’s capacity
weight and the original equipment tire size and
recommended in ation pressure. See “Tire
and Loading Information Label” underLoading
Your Vehicle on page 296.
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In ation - Tire Pressure
Tires need the correct amount of air pressure to
operate effectively.
Notice:Do not let anyone tell you that
under-in ation or over-in ation is all right.
It is not. If your tires do not have enough air
(under-in ation), you can get the following:
Too much exing
Too much heat
Tire overloading
Premature or irregular wear
Poor handling
Reduced fuel economy
If your tires have too much air (over-in ation),
you can get the following:
Unusual wear
Poor handling
Rough ride
Needless damage from road hazardsA Tire and Loading Information label is attached to
the vehicle’s center pillar (B-pillar), below the
driver’s door latch. This label shows your vehicle’s
original equipment tires and the correct in ation
pressures for your tires when they are cold.
The recommended cold tire in ation pressure,
shown on the label, is the minimum amount of air
pressure needed to support your vehicle’s
maximum load carrying capacity.
For additional information regarding how much
weight your vehicle can carry, and an example
of the tire and loading information label, see
Loading Your Vehicle on page 296. How you load
your vehicle affects vehicle handling and ride
comfort, never load your vehicle with more weight
than it was designed to carry.
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When to Check
Check your tires once a month or more.
Also, check the tire pressure of the spare tire.
How to Check
Use a good quality pocket-type gage to check
tire pressure. You cannot tell if your tires are
properly in ated simply by looking at them.
Radial tires may look properly in ated even when
they’re underin ated. Check the tire’s in ation
pressure when the tires are cold. Cold means your
vehicle has been sitting for at least three hours
or driven no more than 1 mile (1.6 km).Remove the valve cap from the tire valve stem.
Press the tire gage rmly onto the valve to
get a pressure measurement. If the cold tire
in ation pressure matches the recommended
pressure on the tire and loading information label,
no further adjustment is necessary. If the
pressure is low, add air until you reach the
recommended amount.
If you over ll the tire, release air by pushing on
the metal stem in the center of the tire valve.
Recheck the tire pressure with the tire gage.
Be sure to put the valve caps back on the valve
stems. They help prevent leaks by keeping out dirt
and moisture.
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High-Speed Operation
{CAUTION:
Driving at high speeds, 100 mph (160 km/h)
or higher, puts an additional strain on tires.
Sustained high-speed driving causes
excessive heat build up and can cause
sudden tire failure. You could have a
crash and you or others could be killed.
Some high-speed rated tires require
in ation pressure adjustment for high
speed operation. When speed limits and
road conditions are such that a vehicle
can be driven at high speeds, make sure
the tires are rated for high speed operation,
in excellent condition, and set to the
correct cold tire in ation pressure for the
vehicle load.
If your vehicle has P255/55R18 104H size tires
installed on the rear axle, they will require
in ation pressure adjustment when driving your
vehicle at speeds above 99 mph (160 km/h).Set the cold in ation pressure, for the rear tires
only, to the maximum in ation pressure shown on
the tire sidewall, or 36 psi (248 kPa), whichever
is lower. See the example following. When you end
this high-speed driving, return the tires to the
cold tire in ation pressure shown on the Tire and
Loading Information label. SeeLoading Your
Vehicle on page 296.
Example:
You will nd the maximum load and in ation
pressure molded on the tire’s sidewall, in small
letters, near the rim ange. It will read something
like this: Maximum load 690 kg (1521 lbs)
300 kPa (44 psi) Max. Press.
For this example, you would set the in ation
pressure for high-speed driving at
36 psi (248 kPa).
The in ation pressure for the front tires should be
set to the cold tire in ation pressure shown on
the Tire and Loading Information label.
Racing or other competitive driving may affect the
warranty coverage of your vehicle. See your
warranty booklet for more information.
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