2008 CADILLAC CTS Owners Manual

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.
{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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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.
Wheel Alignment and Tire Balance
The tires and wheels on your vehicle were aligned and
balanced carefully at the factory to give you the longest
tire life and best overall performance. Adjustments to
wheel alignment and tire balancing will not be necessary
on a regular basis. However, if you notice unusual tire
wear or your vehicle pulling to one side or the other, the
alignment might need to be checked. If you notice your
vehicle vibrating when driving on a smooth road, the tires
and wheels might need to be rebalanced. See your
dealer/retailer for proper diagnosis.
Wheel Replacement
Replace any wheel that is bent, cracked, or badly rusted
or corroded. If wheel nuts keep coming loose, the wheel,
wheel bolts, and wheel nuts should be replaced. If the
wheel leaks air, replace it (except some aluminum
wheels, which can sometimes be repaired). See your
dealer/retailer if any of these conditions exist.
Your dealer/retailer will know the kind of wheel
you need.
Each new wheel should have the same load-carrying
capacity, diameter, width, offset, and be mounted
the same way as the one it replaces.
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If you need to replace any of your wheels, wheel bolts,
wheel nuts, or Tire Pressure Monitor System (TPMS)
sensors, replace them only with new GM original
equipment parts. This way, you will be sure to have
the right wheel, wheel bolts, wheel nuts, and TPMS
sensors 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 5-102for more
information.
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.
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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
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. To help avoid damage to your
vehicle, drive slowly, re-adjust or remove the
device if it is contacting your vehicle, and do
not spin your wheels. If you do nd traction
devices that will t, install them on the rear
tires.
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 5-58. 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.
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If a tire goes at, and your vehicle has a compact
spare tire, seeChanging a Flat Tire on page 5-102.
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.
Tire Sealant and Compressor Kit
If your vehicle has a factory installed tire sealant and
compressor kit, there is no spare tire, no tire changing
equipment and no place to store a tire.
If a tire goes at, avoid further tire and wheel damage
by driving slowly to a level place and stopping.
1. Turn on the hazard warning ashers. SeeHazard
Warning Flashers on page 3-6.
2. Park your vehicle. If your vehicle has an automatic
transmission, set the parking brake rmly and put
the shift lever in PARK (P). SeeShifting Into Park
(Automatic Transmission) on page 2-45. If your
vehicle has a manual transmission, move the
shift lever to REVERSE (R) and set the parking
brake rmly. SeeParking the Vehicle (Manual
Transmission) on page 2-47for additional
information.
3. Turn off the engine.
4. Inspect the at tire.
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If the tire has been separated from the wheel, has
damaged sidewalls, or has a puncture larger than a
14inch (6 mm), the tire is too severely damaged for
the tire sealant and compressor kit to be effective.
SeeRoadside Service on page 7-7.
If the tire has a puncture less than a
14inch (6 mm)
in the tread area of the tire, seeTire Sealant and
Compressor Kit (With Sealant Selector Switch) on
page 5-84orTire Sealant and Compressor Kit
(Without Sealant Selector Switch) on page 5-93.
Tire Sealant and Compressor Kit
(With Sealant Selector Switch)
Your vehicle has a tire sealant and compressor kit that
is capable of temporarily sealing a puncture up to 6 mm in
the tread area of the tire. There is no jack or spare tire.
The kit inates the tire with liquid sealant and air. The tire
sealant and compressor kit can also be used to inate
an underinated tire. After the tire is inated to the
recommended ination pressure, seeInflation - Tire
Pressure on page 5-66for more information, the vehicle
must be driven for ve miles to distribute the sealant in
the tire and seal the puncture. After driving ve miles the
tire pressure must be rechecked and adjusted as needed.See Using the Tire Sealant and Compressor Kit later in
this section. Be sure to read and follow all of the tire
sealant and compressor kit instructions. The kit includes:
A. Selector Switch
B. On/Off Button
C. Air Pressure Gage
D. Tire Sealant
CanisterE. Air Compressor
Accessory Plug
F. Sealant/Air Hose
(Clear)
G. Air Only Hose
After temporarily sealing the tire sealant and compressor
kit, it is recommended to take your vehicle to an
authorized dealer/retailer as soon as possible. If the
sealant is removed within 100 miles (161 kilometers) of
driving, then it is easier to clean from the tire and you are
less likely to require a replacement tire.
5-84

Accessing the Tire Sealant and
Compressor Kit
A. Tire Sealant and Compressor Kit
B. Foam Container
C. Wing Nut
To access the tire sealant and compressor kit:
1. Open the trunk. SeeTrunk on page 2-21for more
information.
2. Locate the tire sealant and compressor kit (A) in the
center of the cargo area.3. Remove the tire sealant and compressor kit by
turning the wing nut (C counterclockwise).
4. Remove the sealant and compressor kit from its
foam container (B).
Tire Sealant
Read and follow the safe handling instructions on the
sealant canister.
The sealant can temporarily seal small punctures in the
tread area of the tire. The sealant cannot seal sidewall
damage, large punctures, or a tire that has unseated
from the wheel. SeeRoadside Service on page 7-7if
you need assistance.
The sealant can only be used to seal one tire. After
usage, the sealant canister and sealant lling hose
assembly must be replaced at a dealer/retailer. See
Removal and Installation of Sealant Canister later in
this section.
Check the tire sealant expiration date on the sealant
canister. The sealant might not be effective beyond
the expiration date. If needed, see your dealer/retailer
for a replacement canister.
5-85

Using the Tire Sealant and
Compressor Kit
Follow these directions closely for correct sealant
usage.
A. Selector Switch
B. On/Off Button
C. Air Pressure Gage
D. Tire Sealant
CanisterE. Air Compressor
Accessory Plug
F. Sealant/Air Hose
(Clear)
G. Air Only Hose1. Do a safety check before proceeding. SeeIf a Tire
Goes Flat on page 5-82.
2. Inspect the damaged tire.
The sealant cannot seal sidewall damage, large
punctures, or a tire that has unseated from
the wheel. SeeRoadside Service on page 7-7.
Do not remove any objects that have penetrated
the tire.
3. Place the sealant and compressor kit on the ground
and unwrap the sealant/air hose (F) hose from the
compressor.
The sealant/air hose (F) is the top, clear hose.
4. Remove the valve stem cap from the at tire by
turning it counterclockwise.
5. Attach the sealant lling hose (F) onto the tire valve
stem. Turn it clockwise until it is tight.
6. Unwrap and plug the air compressor accessory
plug (E) into an accessory power outlet in the
vehicle. SeeAccessory Power Outlet(s) on
page 3-22for more information.
Do not pinch the compressor accessory plug cord in
the door or window.
5-86