2007 CADILLAC STS V brake

(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/transaxle, 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.
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TPMS Sensor Identication Codes
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
GM dealer for service.
The TPMS sensors may also be matched to each
tire/wheel position by increasing or decreasing
the tire’s air pressure. When increasing the tire’s
pressure, do not exceed the maximum ination
pressure indicated on the tire’s sidewall. If
using this method to match TPMS sensors, the
complete procedure outlined below must be
performed within 15 minutes of the vehicle being
stationary.You will have one minute to match the rst
tire/wheel position, and ve minutes overall, to
match all four tire/wheel positions. If it takes longer
than one minute to match the rst tire and
wheel, or more than ve minutes to match all
four tire/wheel positions, the matching process
stops and you will need to start over.
The TPM matching process is outlined below:
1. Set the parking brake.
2. Press the push-button ignition switch to Acc.
(Off/Accessory).
3. Using the Keyless Access transmitter, lock
and unlock the vehicle’s doors.
4. Press the lock and unlock buttons, at the
same time, on the Keyless Access
transmitter. A single horn chirp will sound,
indicating that the TPMS is ready, and
the sensor matching process can begin.
5. Start with the driver’s side front tire.
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Buying New Tires
GM has developed and matched specic tires for
your vehicle. The original equipment tires
installed on your vehicle, when it was new, were
designed to meet General Motors Tire
Performance Criteria Specication (TPC Spec)
system rating. If you need replacement tires, GM
strongly recommends that you get tires with
the same TPC Spec rating. This way, your vehicle
will continue to have tires that are designed to
give the same performance and vehicle safety,
during normal use, as the original tires.
GM’s exclusive TPC Spec system considers over
a dozen critical specications that impact the
overall performance of your vehicle, including
brake system performance, ride and handling,
traction control, and tire pressure monitoring
performance. GM’s TPC Spec number is moldedonto the tire’s sidewall by the tire manufacturer. If
the tires have an all-season tread design, the
TPC Spec number will be followed by an MS for
mud and snow. SeeTire Sidewall Labeling on
page 423for additional information.
The optional 18-inch performance tires, size
255/45ZR18 99Y, used on some vehicles, meet
the General Motors Tire Performance Criteria
Specication (TPC Spec) rating but the TPC Spec
code has not been molded onto the tire’s
sidewall. If your vehicle has these tires, and you
need to replace them, you can still get these TPC
Spec rated tires by asking your GM dealer.
Your GM dealer can order these tires by part
number. This way, your vehicle will continue to
give the proper endurance, handling, traction, and
ride as the original tires.
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Your vehicle’s original equipment tires are listed
on the Tire and Loading Information label.
This label is attached to the vehicle’s center pillar
(B-pillar). SeeLoading Your Vehicle on page 349,
for more information about the Tire and Loading
Information label and its location on your vehicle.
Vehicles that have performance tires
P235/50R17 95V (front axle) and P255/45R17 98V
(rear axle) are mounted on wheels with different
rim widths. The front axle tires are mounted
on rims 7.5 inches (19.05 cm) wide and the rear
axle tires require wheels with a minimum rim width
of 8 inches (20.32 cm). The original equipment
wheels designed for P255/45R17 98V size
tires are etched with the words REAR ONLY.
When replacing P255/45R17 98V size tires have
them mounted on wheels with a minimum width of
8 inches (20.32 cm) and marked REAR ONLY.
SeeWheel Replacement on page 445.
Different Size Tires and Wheels
If you add wheels or tires that are a different size
than your original equipment wheels and tires,
this may affect the way your vehicle performs,
including its braking, ride and handling
characteristics, stability, and resistance to rollover.Additionally, if your vehicle has electronic systems
such as, anti-lock brakes, traction control, and
electronic stability control, the performance
of these systems can be affected.
{CAUTION:
If you add different sized wheels, your
vehicle may not provide an acceptable
level of performance and safety if tires not
recommended for those wheels are
selected. You may increase the chance
that you will crash and suffer serious
injury. Only use GM specic wheel and
tire systems developed for your vehicle,
and have them properly installed by a GM
certied technician.
SeeBuying New Tires on page 441and
Accessories and Modications on page 363for
additional information.
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Each new wheel should have the same
load-carrying capacity, diameter, width, offset and
be mounted the same way as the one it
replaces.
If you need to replace any of your wheels, wheel
bolts, or wheel nuts, replace them only with
new GM original equipment parts. This way, you
will be sure to have the right wheel, wheel
bolts, and wheel nuts for your vehicle.
{CAUTION:
Using the wrong replacement wheels,
wheel bolts, or wheel nuts on your vehicle
can be dangerous. It could affect the
braking and handling of your vehicle,
make your tires lose air and make you
lose control. You could have a collision in
which you or others could be injured.
Always use the correct wheel, wheel bolts,
and wheel nuts for replacement.Notice:The wrong wheel can also cause
problems with bearing life, brake cooling,
speedometer or odometer calibration,
headlamp aim, bumper height, vehicle ground
clearance, and tire or tire chain clearance
to the body and chassis.
SeeChanging a Flat Tire on page 464for more
information.
Used Replacement Wheels
{CAUTION:
Putting a used wheel on your vehicle is
dangerous. You cannot know how it has
been used or how far it has been driven. It
could fail suddenly and cause a crash. If
you have to replace a wheel, use a new
GM original equipment wheel.
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Tire Chains
{CAUTION:
If your vehicle has P255/45R17,
P255/45R18, P275/40R19, or 255/45ZR18
size tires, do not use tire chains, as there
is not enough clearance.
Tire chains used on a vehicle without the
proper amount of clearance can cause
damage to the brakes, suspension, or
other vehicle parts. The area damaged by
the tire chains could cause you to lose
control of your vehicle and you or others
may be injured in a crash.
Use another type of traction device only if
its manufacturer recommends it for use
on your vehicle and tire size combination
and road conditions. Follow that
manufacturer’s instructions.
CAUTION: (Continued)
CAUTION: (Continued)
To help avoid damage to your vehicle,
drive slowly, readjust, or remove the
device if it is contacting your vehicle, and
do not spin your vehicle’s wheels.
If you do nd traction devices that will t,
install them on the rear tires only.
Notice:If your vehicle has P235/50R17 95S
size tires, use tire chains only where legal and
only when you must. Use only SAE Class
S-type chains that are the proper size for your
tires. Install them on the rear tires and
tighten them as tightly as possible with the
ends securely fastened. Drive slowly and follow
the chain manufacturer’s instructions. If you
can hear the chains contacting your vehicle,
stop and retighten them. If the contact
continues, slow down until it stops. Driving
too fast or spinning the wheels with chains on
will damage your vehicle.
447

Lifting Your Vehicle (STS-V)
{CAUTION:
Lifting a vehicle can cause an injury. The
vehicle can slip off the jack and roll over
you or other people. You and they could
be badly injured. Find a level place to lift
your vehicle. To help prevent the vehicle
from moving:
1. Hold the brake pedal down with your
right foot.
2. Move the shift lever in PARK (P) by
pressing the button on the front of
the shift lever while pushing the lever
all the way toward the front of the
vehicle. Release the button.
3. With your right foot still holding the
brake pedal down, set the parking
brake with your left foot.
4. Turn off the engine.
CAUTION: (Continued)
CAUTION: (Continued)
To be even more certain the vehicle will
not move, you can put blocks in front of
and behind the wheels. Also, seeShifting
Into Park (P) on page 122andParking
Brake on page 121for additional
information.
{CAUTION:
Getting under a vehicle when it is jacked
up is dangerous. If the vehicle slips off
the jack, you could be badly injured or
killed. Never get under a vehicle when it is
supported only by a jack.
448

If a Tire Goes Flat
It is unusual for a tire to blowout while you are
driving, especially if you maintain your tires
properly. SeeTires on page 421. If air goes out of
a tire, It is much more likely to leak out slowly.
But if you should ever have a blowout, here are a
few tips about what to expect and what to do:
If a front tire fails, the at tire will create a drag that
pulls the vehicle toward that side. Take your
foot off the accelerator pedal and grip the steering
wheel rmly. Steer to maintain lane position,
and then gently brake to a stop well out of the
traffic lane.
A rear blowout, particularly on a curve, acts much
like a skid and may require the same correction
you would use in a skid. In any rear blowout,
remove your foot from the accelerator pedal. Get
the vehicle under control by steering the way
you want the vehicle to go. It may be very bumpy
and noisy, but you can still steer. Gently brake
to a stop, well off the road if possible.If a tire goes at, and your vehicle has a compact
spare tire, seeChanging a Flat Tire on page 464.
This information shows you how to use your
vehicle’s tire changing equipment and how
to change a at tire safely.
{CAUTION:
Lifting a vehicle and getting under it to do
maintenance or repairs is dangerous
without the appropriate safety equipment
and training. The jack provided with your
vehicle is designed only for changing a
at tire. If it is used for anything else, you
or others could be badly injured or killed
if the vehicle slips off the jack. Use the
jack provided with your vehicle only for
changing a at tire.
If your vehicle has 255/45ZR18 size tires, there is
no spare tire, jack, or tire changing equipment.
A tire inator kit, included with your vehicle, may
be used to seal small punctures in the tread
area of the tire. SeeTire Inator Kit on page 452.
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