Tire BUICK LESABRE 2004 Service Manual

(A) Tire Size:The tire size code is a combination of
letters and numbers used to dene 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) Tire Performance Criteria Specication (TPC
Spec):Original equipment tires designed to GM’s
specic tire performance criteria have a TPC
specication code molded onto the sidewall. GM’s TPC
specications meet or exceed all federal safety
guidelines.
(C) 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.
(D) Tire Identication Number (TIN):The letters and
numbers following DOT code are the Tire Identication
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 Car Tire Example
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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 see
Uniform Tire Quality Grading on page 5-70.
(G) Maximum Cold Ination Load Limit:Maximum
load that can be carried and the maximum pressure
needed to support that load. For more information on
recommended tire pressure seeInation - Tire Pressure
on page 5-65andLoading Your Vehicle on page 4-33.
Compact Spare Tire Example
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(A) Temporary Use Only:The compact spare tire or
temporary use tire has a tread life of approximately
3,000 miles (5 000 km) and should not be driven
at speeds over 65 mph (105 km/h). The compact spare
tire is for emergency use when a regular road tire
has lost air and gone at. SeeCompact Spare Tire on
page 5-83andIf a Tire Goes Flat on page 5-73.
(B) Tire Ply Material:The type of cord and number of
plies in the sidewall and under the tread.
(C) Tire Identication Number (TIN):The Tire
Identication 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.
(D) Maximum Cold Ination Load Limit:Maximum
load that can be carried and the maximum pressure
needed to support that load. SeeCompact Spare Tire
on page 5-83andLoading Your Vehicle on page 4-33.(E) Tire Ination:The temporary use tire or compact
spare tire should be inated to 60 psi (420 kPa).
For more information on tire pressure and ination see
Ination - Tire Pressure on page 5-65.
(F) Tire Size:A combination of letters and numbers
dene a tire’s width, height, aspect ratio, construction
type and service description. The letter “T” as the
rst character in the tire size means the tire is for
temporary use only.
(G) Tire Performance Criteria Specication (TPC
Spec):Original equipment tires designed to GM’s
specic tire performance criteria have a TPC
specication code molded onto the sidewall. GM’s TPC
specications meet or exceed all federal safety
guidelines.
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Tire Size
The following illustration shows an example of a typical
passenger car tire size.
(A) P-Metric Tire:The United States version of a
metric tire sizing system. The letter “P” as the
rst character in the tire size means a passenger
vehicle tire engineered to standards set by the U. S.
Tire and Rim Association.
(B) Tire Width:The three-digit number indicates the
tire section width in millimeters from sidewall to sidewall.
(C) Aspect Ratio:A two-digit number that indicates
the tire height-to-width measurements. For example, if
the tire size aspect ratio is “70,” as shown in item “C” of
the illustration, it would mean that the tire’s sidewall is
70% as high as it is wide.(D) Construction Code: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 construction; and the letter “B”
means belted-bias ply construction.
(E) Rim Diameter:Diameter of the wheel in inches.
(F) Service Description:These characters represent
the load range and the speed rating of a tire. The
load range represents the load carrying capacity a tire is
certied to carry. The load index can range from 1 to
279. The speed rating is the maximum speed a tire
is certied to carry a load. Speed ratings range from
“A” to “Z”.
Tire Terminology and Denitions
Air Pressure:The amount of air inside the tire pressing
outward on each square inch of the tire. Air pressure
is expressed in pounds per square inch (psi) or
kilopascal (kPa).
Accessory Weight:This means the combined weight
of optional accessories. Some examples of optional
accessories are, automatic transmission, power steering,
power brakes, power windows, power seats, and air
conditioning.
Aspect Ratio:The relationship of a tire’s height to its
width.
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Belt:A rubber coated layer of cords that is located
between the plies and the tread. Cords may be made
from steel or other reinforcing materials.
Bead:The tire bead contains steel wires wrapped by
steel cords that hold the tire onto the rim.
Bias Ply Tire:A pneumatic tire in which the plies
are laid at alternate angles substantially less than
90 degrees to the centerline of the tread.
Cold Ination Pressure:The amount of air pressure in
a tire, measured in pounds per square inch (psi)
before a tire has built up heat from driving. See
Ination - Tire Pressure on page 5-65.
Curb Weight:This means the weight of a motor
vehicle with standard and optional equipment including
the maximum capacity of fuel, oil and coolant, but
without passengers and cargo.
DOT Markings:A code molded into the sidewall of a
tire signifying that the tire is in compliance with the U.S.
Department of Transportation motor vehicle safety
standards. The DOT code includes the Tire Identication
Number (TIN), an alphanumeric designator which can
also identify the tire manufacturer, production plant,
brand and date of production.
GVWR:Gross Vehicle Weight Rating, seeLoading
Your Vehicle on page 4-33.
GAWR FRT:Gross Axle Weight Rating for the front
axle, seeLoading Your Vehicle on page 4-33.GAWR RR:Gross Axle Weight Rating for the rear axle,
seeLoading Your Vehicle on page 4-33.
Intended Outboard Sidewall:The side of an
asymmetrical tire that must always face outward when
mounted on a vehicle.
Kilopascal (kPa):The metric unit for air pressure.
There are 6.9 kPa’s to one psi.
Light Truck (LT-Metric) Tire:A tire used on light duty
trucks and some multipurpose passenger vehicles.
Load Index:An assigned number ranging from
1 to 279 that corresponds to the load carrying capacity
of a tire.
Maximum Ination Pressure:The maximum air
pressure to which a cold tire may be inated. The
maximum air pressure is molded onto the sidewall.
Maximum Load Rating:The load rating for a tire at the
maximum permissible ination pressure for that tire.
Maximum Loaded Vehicle Weight:The sum of curb
weight; accessory weight; vehicle capacity weight;
and production options weight.
Normal Occupant Weight:The number of occupants a
vehicle is designed to seat multiplied by 150 pounds
(68 kg). SeeLoading Your Vehicle on page 4-33.
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Occupant Distribution:Designated seating positions.
Outward Facing Sidewall:The side of a asymmetrical
tire that has a particular side that faces outward
when mounted on a vehicle. The side of the tire that
contains a whitewall, bears white lettering or bears
manufacturer, brand and or model name molding that is
higher or deeper than the same moldings on the
other sidewall of the tire.
Passenger (P-Metric) Tire:A tire used on passenger
cars and some light duty trucks and multipurpose
vehicles.
Recommended Ination Pressure:Vehicle
manufacturer’s recommended tire ination pressure and
shown on the tire placard. SeeInation - Tire Pressure
on page 5-65andLoading Your Vehicle on page 4-33.
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 2/32 inch of tread remains. SeeWhen It
Is Time for New Tires on page 5-68.
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 5-70.
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 4-33.
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 original equipment tire size
and recommended ination pressure. SeeLoading Your
Vehicle on page 4-33.
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Ination - Tire Pressure
The tire and loading information label, shows the correct
ination pressures for your tires when they’re cold.
“Cold” means your vehicle has been sitting for at least
three hours or driven no more than 1 mile (1.6 km). See
Loading Your Vehicle on page 4-33, for the location
of your vehicle’s tire and loading information label.
Notice:Don’t let anyone tell you that underination
or overination is all right. It’s not. If your tires
don’t have enough air (underination), you can get
the following:
Too much exing
Too much heat
Tire overloading
Bad wear
Bad handling
Bad fuel economy
If your tires have too much air (overination), you
can get the following:
Unusual wear
Bad handling
Rough ride
Needless damage from road hazards
When to Check
Check your tires once a month or more.
Don’t forget your compact spare tire. It should be at
60 psi (420 kPa).
How to Check
Use a good quality pocket-type gage to check tire
pressure. You can’t tell if your tires are properly inated
simply by looking at them. Radial tires may look
properly inated even when they’re underinated. Check
the tire’s ination 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 ination pressure matches
the recommended pressure on the Tire and Loading
Information label, no further adjustment is necessary. If
the ination pressure is low, add air until you reach
the recommended amount.
If you overll 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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Check Tire Pressure System
If your vehicle has the check tire pressure system, it
can alert you to a large change in the pressure of one
tire. The system will not alert you before you drive
that a tire is low or at. You must begin driving before
the system will work properly.
The CHECK TIRE PRESSURE message will appear on
the Driver Information Center (DIC) if pressure
difference (low pressure) is detected in one tire. The
check tire pressure system may not alert you if:
More than one tire is low.
The vehicle is moving faster than
65 mph (105 km/h).
The system is not yet calibrated.
The tire treadwear is uneven.
The compact spare tire is installed.
Tire chains are being used.
The vehicle is being driven on a rough or
frozen road.
If the anti-lock brake system warning light comes on,
the check tire pressure system may not be working
properly. See your dealer for service. Also, see
Anti-Lock Brake System Warning Light on page 3-38.The check tire pressure system detects differences in
tire rotation speeds that are caused by changes in
tire pressure. The system can alert you about a
low tire — but it does not replace normal tire
maintenance. SeeTires on page 5-58.
When the CHECK TIRE PRESSURE message appears
on the Driver Information Center, you should stop as
soon as you can and check all your tires for damage. If
a tire is at, seeIf a Tire Goes Flat on page 5-73.
Also check the tire pressure in all four tires as soon as
you can. SeeInation - Tire Pressure on page 5-65.
Any time you adjust a tire’s pressure or have one
or more tires repaired or replaced, you will need to reset
(calibrate) the check tire pressure system. You will
also need to reset the system whenever you rotate the
tires, buy new tires and install or remove the compact
spare tire.
Do not reset the check tire pressure system without rst
correcting the cause of the problem and checking
and adjusting the pressure in all four tires. If you reset
the system when the tire pressures are incorrect,
the check tire pressure system will not work properly
and may not alert you when a tire is low or high.
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To reset (calibrate) the system:
1. Turn the ignition switch to RUN.
2. Press the GAGE INFO button on the DIC until TIRE
PRESSURE appears on the display.
3. Press and hold the DIC RESET button for about
ve seconds. After ve seconds, the display will
show TIRE PRESSURE RESET. If TIRE
PRESSURE RESET does not appear in the display
after about ve seconds repeat the procedure. If
it does not work after two tries, see your dealer for
service. After you release the DIC RESET button,
TIRE PRESSURE NORMAL will appear in the
display.
The system completes the calibration process during
driving. Calibration time can take 45 to 90 minutes,
depending on your driving habits. After the system
has been calibrated, the system will alert the driver
that a tire is low, up to a maximum speed of 65 mph
(105 km/h).Tire Inspection and Rotation
Tires should be rotated every 5,000 to 8,000 miles
(8 000 to 13 000 km).
Any time you notice unusual wear rotate your tires as
soon as possible and check wheel alignment. Also
check for damaged tires or wheels. SeeWhen It Is Time
for New Tires on page 5-68andWheel Replacement
on page 5-71for more information.
The purpose of regular rotation is to achieve more
uniform wear for all tires on the vehicle. The rst rotation
is the most important. SeePart A: Scheduled
Maintenance Services on page 6-4, for scheduled
rotation intervals.
When rotating your tires, always use the correct rotation
pattern shown here.
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Don’t include the compact spare tire in your tire rotation.
After the tires have been rotated, adjust the front and
rear ination pressures as shown on the Tire and
Loading Information label.
Reset the check tire pressure system, if equipped. See
Check Tire Pressure System on page 5-66.
Make certain that all wheel nuts are properly tightened.
See “Wheel Nut Torque” underCapacities and
Specications on page 5-99.
{CAUTION:
Rust or dirt on a wheel, or on the parts to
which it is fastened, can make wheel nuts
become loose after a time. The wheel could
come off and cause an accident. When you
change a wheel, remove any rust or dirt from
places where the wheel attaches to the vehicle.
In an emergency, you can use a cloth or a
paper towel to do this; but be sure to use a
scraper or wire brush later, if you need to, to
get all the rust or dirt off. See “Changing a Flat
Tire” in the Index.
When It Is Time for New Tires
One 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.
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