2009 CADILLAC XLR service

(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 6-64.
(G) Maximum Cold Ination Load Limit
:Maximum load that can be carried and the
maximum pressure needed to support that load.
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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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 25 miles (40 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.
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 orreplacement. To locate the nearest GM or run-at
servicing facility, call Roadside Assistance. For phone
numbers and Roadside Service details seeRoadside
Service on page 8-7.
{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 6-55. These
sensors contain batteries which are designed to last
for 10 years under normal driving conditions. See your
dealer/retailer if you ever need to have a wheel
replaced, or if the sensors ever need replacement.
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Federal Communications Commission
(FCC) and Industry and Science Canada
The Tire Pressure Monitor System (TPMS) operates
on a radio frequency and complies with Part 15 of
the FCC Rules. Operation is subject to the following
two conditions:
1. This device may not cause harmful interference.
2. This device must accept any interference received,
including interference that may cause undesired
operation.
The TPMS operates on a radio frequency and complies
with RSS-210 of Industry and Science Canada.
Operation is subject to the following two conditions:
1. This device may not cause interference.
2. This device must accept any interference received,
including interference that may cause undesired
operation of the device.
Changes or modications to this system by other than
an authorized service facility could void authorization to
use this equipment.
Tire Pressure Monitor Operation
This vehicle may have a Tire Pressure Monitor
System (TPMS). The TPMS is designed to warn the
driver when a low tire pressure condition exists. TPMS
sensors are mounted onto each tire and wheel
assembly on your vehicle. The TPMS sensors monitor
the air pressure in the vehicle’s tires and transmits
the tire pressure readings to a receiver located in the
vehicle.
When a low tire pressure
condition is detected, the
TPMS illuminates the low
tire pressure warning light,
located in the instrument
panel cluster.
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TPMS Malfunction Light and Message
The TPMS will not function properly if one or more of the
TPMS sensors are missing or inoperable. When the
system detects a malfunction, the low tire warning light
ashes for about one minute and then stays on for the
remainder of the ignition cycle. A DIC warning message
is also displayed. The low tire warning light and DIC
warning message come on at each ignition cycle until the
problem is corrected. Some of the conditions that can
cause the malfunction light and DIC message to come
on are:
The TPMS sensor matching process was not done
or not completed successfully. The DIC message
should go off after successfully completing the
sensor matching process.
One or more TPMS sensors are missing or
damaged. Under these conditions the TPMS
malfunction light (low tire warning light) comes on,
and at the same time the DIC message is displayed.
The DIC message and TPMS malfunction light
should go off once the TPMS sensors are installed
and the sensor matching process is performed
successfully.
Replacement tires or wheels do not match your
vehicle’s original equipment tires or wheels. Tires
and wheels other than those recommended for your
vehicle could prevent the TPMS from functioning
properly. SeeBuying New Tires on page 6-62.
Operating electronic devices or being near facilities
using radio wave frequencies similar to the TPMS
could cause the TPMS sensors to malfunction.
If the TPMS is not functioning it cannot detect or
signal a low tire condition. See your dealer/retailer
for service if the TPMS malfunction light and DIC
message comes on and stays on.
TPMS Sensor Matching Process
Each TPMS sensor has a unique identication code.
Any time you replace one or more of the TPMS sensors
or rotate your vehicle’s tires, the identication codes
will need to be matched to the new tire/wheel position.
The sensors are matched to the tire/wheel positions
in the following order: driver side front tire, passenger
side front tire, passenger side rear tire, and driver
side rear tire using a TPMS diagnostic tool. See your
dealer/retailer for service.
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Tire Inspection and Rotation
We recommend that you regularly inspect your
vehicle’s tires for signs of wear or damage.
SeeWhen It Is Time for New Tires on page 6-61
for additional information.
If your vehicle has P235/50R18 size tires they
should be rotated any time you notice unusual
wear. Rotate the 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 6-61andWheel Replacement on
page 6-66.
When rotating P235/50R18 size tires, always use
the correct rotation pattern shown here.After the tires have been rotated, adjust the front
and rear ination pressures as shown on the Tire
and Loading Information label, seeInflation - Tire
Pressure on page 6-54andLoading the Vehicle on
page 5-21. Vehicles that have the Tire Pressure
Monitor System (TPMS) need the TPMS sensors
reset after a tire rotation is performed. A special tool
is needed to reset the sensor identication codes.
See your dealer/retailer for service. Make certain
that all wheel nuts are properly tightened. See
Wheel Replacement on page 6-66and “Wheel Nut
Torque” underCapacities and Specifications on
page 6-90
.
{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 a crash. 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.
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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 (NHTSA), 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 (UTQG)
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 specied 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 signicantly 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 specied government test
surfaces of asphalt and concrete. A tire marked C
may have poor traction performance.
6-64

{CAUTION:
Raising the vehicle with the jack improperly
positioned can damage the vehicle or the vehicle
may fall and cause your or others injury.
If you ever use a jack to lift the vehicle, follow the
instructions that came with the jack, and be sure to use
the correct lifting points to avoid damaging the vehicle.
Notice:Lifting the vehicle improperly can damage
the vehicle and result in costly repairs not covered
by the vehicle’s warranty. To lift the vehicle
properly, follow the advice in this part.
To help prevent vehicle damage:
Be sure to place a block or pad between the
jack and the vehicle.
Make sure the jack you are using spans at least
two crossmember ribs.
Lift only in the areas shown in the following
pictures.
For additional information, see your GM dealer and
the Cadillac XLR service manual.
Lifting From the Front
The front lifting points can be accessed from either side
of the vehicle, behind the front tires.
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3. Lift the vehicle with the jack, making sure the jack
spans at least two of the crossmember ribs (B).
For more information, seeDoing Your Own Service
Work on page 6-4.
If a Tire Goes Flat
It is unusual for a tire to blow out while you are driving,
especially if you maintain the tires properly. If air
goes out of a tire, it is much more likely to leak out
slowly. SeeTires on page 6-46for additional
information.
This vehicle, when new, had run-at tires. This type of tire
can operate effectively with no air pressure, so you will
not need to stop on the side of the road to change a at
tire. You can just keep on driving. The shorter the
distance you drive and the slower the speed, the greater
the chance that the run-at tire will not have to be
replaced. 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. SeeRun-Flat Tires on page 6-52
andTire Pressure Monitor System on page 6-55.
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