2006 CADILLAC XLR V Owners Manual

Tire Size
The following illustration shows an example of a typical
passenger (p-metric) vehicle tire size.
(A) Passenger (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 60, as shown in item C of
the illustration, it would mean that the tire’s sidewall
is 60 percent 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 speed rating of the tire. The load
index represents the load carry 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.
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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.
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 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)
or kilopascals (kPa) before a tire has built up heat from
driving. SeeInation - Tire Pressure on page 6-58.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 (DOT) 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 5-33.
GAWR FRT:Gross Axle Weight Rating for the front
axle, seeLoading Your Vehicle on page 5-33.
GAWR RR:Gross Axle Weight Rating for the rear axle,
seeLoading Your Vehicle on page 5-33.
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.
Light Truck (LT-Metric) Tire:A tire used on light duty
trucks and some multipurpose passenger vehicles.
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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 lbs (68 kg).
SeeLoading Your Vehicle on page 5-33.
Occupant Distribution:Designated seating positions.
Outward Facing Sidewall:The side of an
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 6-58andLoading Your Vehicle on page 5-33.
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 1/16 inch (1.6 mm) of tread remains.
SeeWhen It Is Time for New Tires on page 6-63.
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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 6-66.
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 5-33.
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 vehicle’s capacity weight and
the original equipment tire size and recommended
ination pressure. See “Tire and Loading Information
Label” underLoading Your Vehicle on page 5-33.Run-Flat Tires
Your vehicle, when new, had run-at tires. There is no
spare tire, no tire changing equipment, and no place
to store a tire in the vehicle. Run-at tires perform
so well without any air that a Tire Pressure Monitor
(TPM) is used to alert you if a tire has lost pressure.
If a tire goes at, you will not need to stop on the side
of the road to change the tire. You can just keep on
driving. The shorter the distance you drive and the
slower the speed, the greater the chance that the tire
will not have to be replaced. If you drive on a deated
run-at tire for 50 miles (80 km) or less and at speeds of
55 mph (90 km/h) or less, there is a good chance that
the tire can be repaired. The tire can operate effectively
with no air pressure for up to 100 miles (160 km) at
speeds up to 55 mph (90 km/h), but the tire would then
have to be replaced. When a tire is lled with air, it
provides a cushion between the road and the wheel.
Because you will not have this cushion when driving on
a deated tire, try to avoid potholes that could damage
your wheel and require replacement of it.
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Some road hazards can damage a tire beyond repair.
This damage could occur even before you have
driven on the tire in a deated condition. When a tire
has been damaged, or if you have driven any distance
on a run-at tire, check with an authorized run-at
tire service center to determine whether the tire can be
repaired or should be replaced. To maintain your
vehicle’s run-at feature, all replacement tires must be
self-supporting tires. As soon as possible, contact
the nearest authorized GM or run-at servicing facility
for inspection and repair or replacement. To locate
the nearest GM or run-at servicing facility, call
Roadside Assistance. For phone numbers and Roadside
Service details seeRoadside Service on page 8-6.
{CAUTION:
Run-at tires are constructed differently than
other tires and could explode during improper
service. You or others could be injured or killed
if you attempt to repair, replace, dismount, or
mount a run-at tire. Let only an authorized
run-at service center repair, replace, dismount,
and mount run-at tires.The valve stems on your run-at tires have sensors that
are part of the Tire Pressure Monitor System (TPMS).
SeeTire Pressure Monitor System on page 6-59.
These sensors contain batteries which are designed to
last for 10 years under normal driving conditions.
See your dealer if you ever need to have a wheel
replaced, or if the sensors ever need replacement.
Notice:Using liquid sealants can damage the tire
valves and tire pressure monitor sensors in your
vehicle’s run-at tires. This damage would not
be covered by warranty. Do not use liquid sealants
in your vehicle’s run-at tires.
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Ination - Tire Pressure
Tires need the correct amount of air pressure to operate
effectively.
Notice:Do not let anyone tell you that
under-ination or over-ination is all right. It is not.
If your tires do not have enough air (under-ination),
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-ination), 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
center pillar, below the driver’s door latch. This label
shows your vehicle’s original equipment tires and
the correct ination pressures for your tires when they
are cold. The recommended cold tire ination 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, seeLoading Your Vehicle
on page 5-33. How you load your vehicle affects
vehicle handling and ride comfort, never load your
vehicle with more weight than it was designed to carry.
When to Check
Check your tires once a month or more.
How to Check
Use a good quality pocket-type gage to check tire
pressure. You cannot tell if your tires are properly inated
simply by looking at them. Radial tires may look properly
inated even when they are 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).
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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.
Tire Pressure Monitor (TPM)
Your vehicle has a Tire Pressure Monitor (TPM) that
sends tire pressure information to the Driver Information
Center (DIC). Using the DIC control buttons, the
driver is able to check tire pressure levels in all four
road tires. SeeTire Pressure Monitor System on
page 6-59andDIC Controls and Displays on page 3-64
for additional information.
Tire Pressure Monitor System
The Tire Pressure Monitor System (TPMS) on your
vehicle, uses radio and sensor technology to check tire
pressure levels. Sensors, mounted on each tire and
wheel assembly transmit tire pressure readings to
a receiver located in the vehicle. The TPMS sensors
transmit tire pressure readings once every 60 seconds
while the vehicle is being driven and once every
60 minutes when the vehicle is stationary for more than
15 minutes. Using the Driver Information Center
(DIC), tire pressure levels can be viewed by the driver.
The TPMS also uses the DIC to warn the driver
when air pressure, in one or more tires, falls below
25 psi (172 kPa) or is above 42 psi (290 kPa).
For additional information and details about the
DIC operation and displays seeDIC Controls and
Displays on page 3-64andDIC Warnings and
Messages on page 3-67.
A low tire pressure warning light also appears on the
instrument panel cluster when a low tire condition exists.
The DIC message, CHECK TIRE PRESSURE and
the low tire pressure warning light will be shown each
time the engine is started and stays on until the low tire
condition is corrected.
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Each tire, including the spare (if provided), should be
checked monthly when cold and inated to the ination
pressure recommended by the vehicle manufacturer
on the vehicle placard or tire ination pressure label.
(If your vehicle has tires of a different size than the
size indicated on the vehicle placard or tire ination
pressure label, you should determine the proper
tire ination pressure for those tires.)
As an added safety feature,
your vehicle has been
equipped with a tire
pressure monitoring system
(TPMS) that illuminates a
low tire pressure telltale
when one or more of your
tires is signicantly
under-inated.Accordingly, when the low tire pressure telltale
illuminates, you should stop and check your tires as
soon as possible, and inate them to the proper
pressure. Driving on a signicantly under-inated tire
causes the tire to overheat and can lead to tire failure.
Under-ination also reduces fuel efficiency and tire
tread life, and may affect the vehicle’s handling
and stopping ability.
Please note that the TPMS is not a substitute for proper
tire maintenance, and it is the driver’s responsibility to
maintain correct tire pressure, even if under-ination has
not reached the level to trigger illumination of the
TPMS low tire pressure telltale.
The Tire and Loading Information Label (tire information
placard) is attached to the vehicle’s b-pillar. This label
shows the size of your vehicle’s original tires and the
correct ination pressure for your vehicle’s tires when
they are cold. SeeLoading Your Vehicle on page 5-33.
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