2008 CADILLAC DTS tire size

High-Speed Operation
{CAUTION:
Driving at high speeds, 100 mph (160 km/h)
or higher, puts an additional strain on tires.
Sustained high-speed driving causes
excessive heat build up and can cause sudden
tire failure. You could have a crash and you or
others could be killed. Some high-speed rated
tires require ination pressure adjustment for
high speed operation. When speed limits and
road conditions are such that a vehicle can be
driven at high speeds, make sure the tires are
rated for high speed operation, in excellent
condition, and set to the correct cold tire
ination pressure for the vehicle load.If your vehicle has P235/55R17 or P245/50R18 size
tires, and you will be driving at speeds of 100 mph
(160 km/h) or higher, where it is legal, set the cold
ination pressure to the maximum ination pressure
shown on the tire sidewall, or 38 psi (265 kPa),
whichever is lower. See the example following.
Example:
You will nd the maximum load and ination pressure
molded on the tire’s sidewall, in small letters, near
the rim ange. It will read something like this: Maximum
load 690 kg (1521 lbs) 300 kPa (44 psi) Max. Press.
For this example, you would set the ination pressure for
high-speed driving at 38 psi (265 kPa).
When you end this high-speed driving, return the tires to
the cold ination pressure shown on the Tire and Loading
Information label. SeeLoading the Vehicle on page 4-20.
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Tire Pressure Monitor System
The Tire Pressure Monitor System (TPMS) uses radio
and sensor technology to check tire pressure levels.
The TPMS sensors monitor the air pressure in
your vehicle’s tires and transmit tire pressure readings
to a receiver located in the vehicle.
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.
Your vehicle has also been equipped with a TPMS
malfunction indicator to indicate when the system is not
operating properly. The TPMS malfunction indicator is
combined with the low tire pressure telltale. When the
system detects a malfunction, the telltale will ash
for approximately one minute and then remain
continuously illuminated. This sequence will continue
upon subsequent vehicle start-ups as long as the
malfunction exists.
When the malfunction indicator is illuminated, the
system may not be able to detect or signal low tire
pressure as intended. TPMS malfunctions may occur
for a variety of reasons, including the installation of
replacement or alternate tires or wheels on the vehicle
that prevent the TPMS from functioning properly. Always
check the TPMS malfunction telltale after replacing one
or more tires or wheels on your vehicle to ensure that
the replacement or alternate tires and wheels allow the
TPMS to continue to function properly.
SeeTire Pressure Monitor Operation on page 5-64for
additional information.
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At the same time a message to check the pressure in
a specic tire appears on the Driver Information Center
(DIC) display. The low tire pressure warning light and the
DIC warning message come on at each ignition cycle
until the tires are inated to the correct ination pressure.
Using the DIC, tire pressure levels can be viewed by the
driver. For additional information and details about the
DIC operation and displays seeDIC Operation and
Displays on page 3-70andDIC Warnings and Messages
on page 3-75.
The low tire pressure warning light may come on in cool
weather when the vehicle is rst started, and then
turn off as you start to drive. This could be an early
indicator that the air pressure in the tire(s) are getting
low and need to be inated to the proper pressure.A Tire and Loading Information label, attached to
your vehicle, shows the size of your vehicle’s original
equipment tires and the correct ination pressure
for your vehicle’s tires when they are cold. SeeLoading
the Vehicle on page 4-20, for an example of the Tire
and Loading Information label and its location on
your vehicle. Also seeInflation - Tire Pressure on
page 5-60.
Your vehicle’s TPMS can warn you about a low tire
pressure condition but it does not replace normal
tire maintenance. SeeTire Inspection and Rotation
on page 5-68andTires on page 5-52.
Notice:Liquid tire sealants could damage the Tire
Pressure Monitor System (TPMS) sensors. Sensor
damage caused by using a tire sealant is not
covered by your warranty. Do not use liquid tire
sealants.
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If your vehicle has a compact spare tire, it should
not be included in the tire rotation process.
Use the four-tire rotation pattern shown.A ve-tire rotation pattern may be used for your
professional vehicle, if it has a full-size spare
tire and wheel assembly that matches the original
equipment tires and wheels in size, type and
brand. The correct ve-tire rotation pattern is
shown.
After the tires have been rotated, adjust the front
and rear ination pressures as shown on the
Tire and Loading Information label. SeeLoading
the Vehicle on page 4-20.
Four-Tire Rotation PatternFive-Tire Rotation Pattern
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You need new tires 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
cannot be repaired well because of the size or
location of the damage.
The rubber in tires degrades over time, even if they are
not being used. This is also true for the spare tire, if your
vehicle has one. Multiple conditions affect how fast this
aging takes place, including temperatures, loading
conditions, and ination pressure maintenance. With
proper care and maintenance tires will typically wear out
before they degrade due to age. If you are unsure about
the need to replace your tires as they get older, consult
the tire manufacturer for more information.
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 molded onto the tire’s sidewall near the tire
size. 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 5-53for
additional information.
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GM recommends replacing tires in sets of four. This is
because uniform tread depth on all tires will help keep
your vehicle performing most like it did when the tires
were new. Replacing less than a full set of tires can affect
the braking and handling performance of your vehicle.
SeeTire Inspection and Rotation on page 5-68for
information on proper tire rotation.
{CAUTION:
Mixing tires could cause you to lose control of
your vehicle while driving. If you mix tires of
different sizes, brands, or types (radial and
bias-belted tires), the vehicle may not handle
properly, and you could have a crash. Using
tires of different sizes, brands, or types may
also cause damage to your vehicle. Be sure to
use the correct size, brand, and type of tires
on all wheels.
CAUTION: (Continued)
CAUTION: (Continued)
Your vehicle may have a compact spare tire
and wheel assembly. If the vehicle has a
compact spare tire and wheel, they have the
same overall diameter as your vehicle’s
full-size tires and wheels. Because they were
designed and developed for use on your
vehicle, it is all right to drive your vehicle with
the compact spare installed properly. Compact
spare tires are designed for temporary use
only. SeeSpare Tire on page 5-89.
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{CAUTION:
If you use bias-ply tires on your vehicle,
the wheel rim anges could develop
cracks after many miles of driving. A tire
and/or wheel could fail suddenly, causing
a crash. Use only radial-ply tires with the
wheels on your vehicle.
If you must replace your vehicle’s tires with those that
do not have a TPC Spec number, make sure they
are the same size, load range, speed rating, and
construction type (radial and bias-belted tires) as
your vehicle’s original tires.
Vehicles that have a tire pressure monitoring system
could give an inaccurate low-pressure warning if
non-TPC Spec rated tires are installed on your vehicle.
Non-TPC Spec rated tires may give a low-pressure
warning that is higher or lower than the proper warning
level you would get with TPC Spec rated tires.
SeeTire Pressure Monitor System on page 5-63.
Your vehicle’s original equipment tires are listed on
the Tire and Loading Information Label. SeeLoading
the Vehicle on page 4-20, for more information about the
Tire and Loading Information Label and its location on
your vehicle.
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, antilock 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 5-71andAccessories
and Modifications on page 5-3for additional information.
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Used Replacement Wheels
{CAUTION:
Putting a used wheel on the 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.
Tire Chains
{CAUTION:
Do not use tire chains. 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
the 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 the
vehicle and tire size combination and road
conditions. Follow that manufacturer’s
instructions. To help avoid damage to the
vehicle, drive slowly, readjust or remove the
device if it is contacting the vehicle, and do
not spin the vehicle’s wheels. If you do nd
traction devices that will t, install them on
the front tires.
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