2005 CADILLAC CTS V service

Tire Size
The following illustration shows an example of a typical
passenger 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.
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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Run-Flat Tires (CTS-V)
If your vehicle has run-at tires, there is no spare tire
and no tire changing equipment. Your vehicle also has
a Tire Pressure Monitor (TPM) which will alert you if
there is a loss of tire pressure in any of the tires. See
Tire Pressure Monitor System (CTS-V) on page 5-65.
{CAUTION:
When the low tire warning light is displayed on
the instrument panel cluster, your vehicle’s
handling capabilities will be reduced during
severe maneuvers. If you drive too fast, you
could lose control of your vehicle. You or
others could be injured. Don’t drive over
55 mph (90 km/h) when the low tire warning
light is displayed. Drive cautiously and check
your tire pressures as soon as you can.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 tire can operate effectively with no air
pressure for up to 65 miles (105 km) at speeds up
to 55 mph (90 km/h). The shorter the distance you
drive and the slower the speed, the greater the chance
that the tire will not 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 deated run-at 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 deated 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.
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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 Service. SeeRoadside
Service on page 7-5for details.
{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).
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
run-at tires. This damage would not be covered
by warranty. Don’t use liquid sealants in your
run-at tires.
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
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If you have replaced a tire/wheel assembly without
transferring the TPM sensors, the error message will be
displayed. Once you re-install the TPM sensors, the
error message should go off. See your GM dealer
for service if all TPM sensors are installed and the error
message comes on and stays on.
The TPM system operates on a radio frequency subject
to Federal Communications Commission (FCC) Rules
and with Industry and Science Canada.
This device complies with Part 15 of the FCC Rules.
Operation is subject to the following two conditions:
1. this device may not cause interference, and
2. this device must accept any interference received,
including interference that may cause undesired
operation.
This device complies with RSS-210 of Industry Canada.
Operation is subject to the following two conditions:
1. this device may not cause interference, and
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 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 5-69andWheel Replacement
on page 5-72for 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. SeeScheduled Maintenance
on page 6-4.
When rotating your tires, always use the correct rotation
pattern shown here.
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If your vehicle has a compact spare tire, do not include
it in the tire rotation.
After the tires have been rotated, adjust the front and
rear ination pressures as shown on the Tire and
Loading Information label. SeeLoading Your Vehicle
on page 4-33, for an example of the tire and loading
information label and its location on your vehicle.
If your vehicle has run-at tires, the Tire Pressure
Monitor (TPM) system will need to have the sensors
reset after a tire rotation is performed. A special tool is
needed to reset the sensor identication codes. See
your dealer for service.
Make certain that all wheel nuts are properly tightened.
See “Wheel Nut Torque” underCapacities and
Specications on page 5-107.
{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 needed, to get
all the rust or dirt off. SeeChanging a Flat
Tire (CTS) on page 5-76.
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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.
Buying New Tires
To nd out what kind and size of tires your vehicle
needs, look at the tire and loading information label. For
more information about this label and its location on
your vehicle, seeLoading Your Vehicle on page 4-33.
The tires installed on your vehicle when it was new had a
Tire Performance Criteria Specication (TPC Spec)
number on each tire’s sidewall. When you get new tires,
GM recommends that you get tires with that same TPC
Spec number. That way your vehicle will continue to
have tires that are designed to give proper endurance,
handling, speed rating, load range, traction, ride, tire
pressure monitoring system performance and other
things during normal service on your vehicle. If your
tires have an all-season tread design, the TPC number
will be followed by an “MS” (for mud and snow).
Whenever you replace your tires with those not having
a TPC Spec number, make sure they are the same
size, load range, speed rating and construction
type (bias, bias-belted or radial) as your original tires.
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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 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 controlledconditions on specied 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.
Temperature – A, B, C
The temperature grades are A (the highest), B, and C,
representing the tire’s resistance to the generation
of heat and its ability to dissipate heat when tested
under controlled conditions on a specied indoor
laboratory test wheel. Sustained high temperature can
cause the material of the tire to degenerate and
reduce tire life, and excessive temperature can lead to
sudden tire failure. The grade C corresponds to a
level of performance which all passenger car tires must
meet under the Federal Motor Vehicle Safety Standard
No. 109. Grades B and A represent higher levels of
performance on the laboratory test wheel than the
minimum required by law.
Warning: The temperature grade for this tire is
established for a tire that is properly inated and not
overloaded. Excessive speed, underination, or
excessive loading, either separately or in combination,
can cause heat buildup and possible tire failure.
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SeeRun-Flat Tires (CTS-V) on page 5-61andTire
Pressure Monitor System (CTS-V) on page 5-65,
for additional information.
{CAUTION:
Special tools and procedures are required to
service a run-at tire. If these special tools
and procedures aren’t used you or others
could be injured and your vehicle could be
damaged. Always be sure the proper tools
and procedures, as described in the service
manual, are used.
To order a service manual seeService Publications
Ordering Information on page 7-11.
Changing a Flat Tire (CTS)
If a tire goes at, avoid further tire and wheel
damage by driving slowly to a level place.
Turn on your hazard warning ashers.
{CAUTION:
Changing a tire can be dangerous. The vehicle
can slip off the jack and roll over or fall on you
or other people. You and they could be badly
injured or even killed. Find a level place to
change your tire. To help prevent the vehicle
from moving:
1. Set the parking brake rmly.
2. Put an automatic transmission shift lever
in PARK (P), or shift a manual transmission
to FIRST (1) or REVERSE (R).
3. Turn off the engine and do not restart while
the vehicle is raised.
4. Do not allow passengers to remain in the
vehicle.
Put the wheel blocks at the front and rear of the
tire farthest away from the one being changed.
That would be the tire on the other side, at the
opposite end of the vehicle.
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