2004 CADILLAC XLR spare tire

Run-Flat Tires
Your vehicle, when new, had run-¯at tires. There's 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 won't 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 de¯ated
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 200 miles
(320 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 won't have this cushion when
driving on a de¯ated tire, try to avoid potholes that could
damage your wheel and require replacement of it.Some road hazards can damage a tire beyond repair.
This damage could occur even before you've driven
on the tire in a de¯ated condition. When a tire has been
damaged, or if you've 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
see
Roadside Service on page 7-5.
{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.
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A low tire 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 stay on until the low tire
condition is corrected.
When the tire pressure
monitoring system warning
light is lit, one or more
of your tires is signi®cantly
under-in¯ated.
You should stop and check your tires as soon as
possible, and in¯ate them to the proper pressure as
indicated on the vehicle's tire information placard.
Driving on a signi®cantly under-in¯ated tire causes the
tire to overheat and can lead to tire failure.
Under-in¯ation also reduces fuel efficiency and tire tread
life, and may affect the vehicle's handling and stopping
ability. Each tire, including the spare, should be
checked monthly when cold and set to the
recommended in¯ation pressure as speci®ed in the
vehicle placard and owner's manual.The Tire and Loading Information Label (tire information
placard) is either on the rear edge of the driver's door
or the driver's door jamb near the latch. This label shows
the size of your vehicle's original tires and the correct
in¯ation pressure for your vehicle's tires when they
are cold. See
In¯ation - Tire Pressure on page 5-57.
Your vehicle's TPM system can alert you about a low or
high tire pressure condition but it does not replace
normal tire maintenance. See
Tire Inspection and
Rotation on page 5-60
Each TPM sensor has a unique identi®cation code that
is matched to one of the four tire positions on your
vehicle. The tire and wheel assembly positions are, left
front (LF); right front (RF); right rear (RR) and left
rear (LR). Any time you rotate your vehicle's tires or
replace one or more TPM sensors, the identi®cation
codes will need to be matched to the new tire and wheel
position. The TPM matching process is performed in
a speci®c sequence and time limit. A special tool is also
required. See your dealer for service.
The SVC TIRE MONITOR message is displayed when
the TPM system is malfunctioning. For example,
one or more TPM sensors may be inoperable or
missing. See your dealer for service.
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Uniform Tire Quality Grading
Quality grades can be found where applicable on the
tire sidewall between tread shoulder and maximum
section width. For example:
Treadwear 200 Traction AA Temperature A
The following information relates to the system
developed by the United States National Highway
Traffic Safety Administration, which grades tires by
treadwear, traction and temperature performance. (This
applies only to vehicles sold in the United States.)
The grades are molded on the sidewalls of most
passenger car tires. The Uniform 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-production 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
Performance 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 speci®ed government test course.
For example, a tire graded 150 would wear one and
a half (1.5) times as well on the government course as
a tire graded 100. The relative performance of tires
depends upon the actual conditions of their use,
however, and may depart signi®cantly from the norm
due to variations in driving habits, service practices 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 represent the tire's ability
to stop on wet pavement as measured under controlled
conditions on speci®ed government test surfaces of
asphalt and concrete. A tire marked C may have poor
traction performance. Warning: 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.
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Vehicle Identi®cation
Vehicle Identi®cation Number (VIN)
This is the legal identi®er for your vehicle. It appears on
a plate in the front corner of the instrument panel, on
the driver's side. You can see it if you look through the
windshield from outside your vehicle. The VIN also
appears on the Vehicle Certi®cation and Service Parts
labels and the certi®cates of title and registration.
Engine Identi®cation
The 8th character in your VIN is the engine code. This
code will help you identify your engine, speci®cations
and replacement parts.
Service Parts Identi®cation Label
You will ®nd this label on the under side of the spare tire
cover in the trunk. It is very helpful if you ever need to
order parts. On this label is:
·your VIN,
·the model designation,
·paint information and
·a list of all production option and special equipment.
Be sure that this label is not removed from the
vehicle.
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