2006 CADILLAC STS wheel size

Buying New Tires.........................................5-72
Different Size Tires and Wheels......................5-74
Uniform Tire Quality Grading..........................5-75
Wheel Alignment and Tire Balance..................5-76
Wheel Replacement......................................5-76
Tire Chains..................................................5-78
Lifting Your Vehicle (STS-V )..........................5-79
If a Tire Goes Flat........................................5-81
Changing a Flat Tire (STS Only).....................5-83
Removing the Spare Tire and Tools
(STS Only)...............................................5-85
Removing the Flat Tire and Installing
the Spare Tire (STS Only)..........................5-86
Storing a Flat or Spare Tire and Tools
(STS Only)...............................................5-92
Compact Spare Tire (STS Only).....................5-94
Appearance Care............................................5-94
Cleaning the Inside of Your Vehicle.................5-94
Fabric/Carpet...............................................5-96
Leather.......................................................5-96
Instrument Panel, Vinyl, and Other
Plastic Surfaces........................................5-97
Wood Panels...............................................5-97
Speaker Covers............................................5-97
Care of Safety Belts......................................5-97Weatherstrips...............................................5-97
Washing Your Vehicle...................................5-98
Cleaning Exterior Lamps/Lenses.....................5-98
Finish Care..................................................5-98
Windshield and Wiper Blades.........................5-99
Aluminum or Chrome-Plated Wheels................5-99
Tires.........................................................5-100
Sheet Metal Damage...................................5-100
Finish Damage...........................................5-101
Underbody Maintenance...............................5-101
Chemical Paint Spotting...............................5-101
Vehicle Care/Appearance Materials................5-102
Vehicle Identication.....................................5-103
Vehicle Identication Number (VIN)................5-103
Service Parts Identication Label...................5-103
Electrical System..........................................5-104
Add-On Electrical Equipment.........................5-104
Headlamp Wiring........................................5-104
Windshield Wiper Fuses...............................5-104
Power Windows and Other Power Options......5-105
Fuses and Circuit Breakers..........................5-105
Underhood Fuse Block................................5-106
Rear Underseat Fuse Block..........................5-110
Capacities and Specications........................5-116
Section 5 Service and Appearance Care
5-2

Low-Prole Performance Tires
If your vehicle has P255/45R18 99Y size tires on the
front wheels and P275/40R19 100Y size tires on the rear
wheels, they are classied as low-prole performance
tires. These tires are designed for very responsive
driving on wet or dry pavement. You may also notice
more road noise with low-prole performance tires and
that they tend to wear faster. These performance
tires are not rated as all-season tires. Winter tires
are recommended for snow or ice covered roads.
Notice:If your vehicle has low-prole tires, they
are more susceptible to damage from road hazards
or curb impact than standard prole tires. Tire
and/or wheel assembly damage can occur when
coming into contact with road hazards like,
potholes, or sharp edged objects, or when sliding
into a curb. Your GM warranty does not cover
this type of damage. Keep tires set to the correct
ination pressure and, when possible avoid contact
with curbs, potholes, and other road hazards.
Winter Tires
If you expect to drive on snow or ice covered roads
often, you may want to get winter tires for your vehicle.
All season tires provide good overall performance on
most surfaces but they may not offer the traction
you would like or the same level of performance as
winter tires on snow or ice covered roads.
See your dealer for details regarding winter tire
availability and proper tire selection. Also, seeBuying
New Tires on page 5-72.
If you choose to use winter tires:
Use tires of the same brand and tread type on all
four wheel positions.
Use only radial ply tires of the same size,
load range, and speed rating as the original
equipment tires.
Winter tires with the same speed rating as your original
equipment tires may not be available for H, V, W, Y
and ZR speed rated tires. If you choose winter tires with
a lower speed rating, never exceed the tire’s maximum
speed capability.
5-57

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.
5-60

Tire Inspection and Rotation
Tire rotation is not recommended if your vehicle has the
following performance tire combinations:
P235/50R17 size tires on the front wheels and
P255/45R17 size tires on the rear wheels.
P235/50R18 size tires on the front wheels and
P255/45R18 size tires on the rear wheels.
P255/45R18 size tires on the front wheels and
P275/40R19 size tires on the rear wheels.
Different tire sizes should not be rotated front to rear.
Each tire and wheel should only be used in the original
front or rear position it is in.
Tire rotation is recommended if your vehicle is equipped
with P235/50R17 size tires on all four wheel positions
or 255/45ZR18 size tires on all four wheel positions.
These 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 5-71andWheel Replacement
on page 5-76for 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 P235/50R17 size tires or 255/45ZR18
size tires, always use the correct rotation pattern
shown here.
If your vehicle has a compact spare tire, do not include
the compact spare tire 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.
5-70

Vehicles that have the Tire Pressure Monitor System
(TPMS) will need to have the TPMS sensors reset after
a tire rotation, seeTire Pressure Monitor System on
page 5-66.
Make certain that all wheel nuts are properly tightened.
See “Wheel Nut Torque” underCapacities and
Specications on page 5-116.
{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
(STS Only) on page 5-83.
When It Is Time for New Tires
One way to tell when it is
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
cannot be repaired well because of the size or
location of the damage.
5-71

{CAUTION:
Mixing tires could cause you to lose control
while driving. If you mix tires of different sizes
(other than those originally installed on
your vehicle), 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 (other than those
originally installed on your vehicle), 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. It is all right to drive
with your vehicle’s compact spare temporarily,
it was developed for use on your vehicle. See
Compact Spare Tire (STS Only) on page 5-94.
{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.
5-73

Vehicles that have a tire pressure monitoring system
may give an inaccurate low-pressure warning if non-TPC
Spec rated tires are installed on it. 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 5-66.
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). See
Loading Your Vehicle on page 4-32, 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 5-76.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 5-72andAccessories
and Modications on page 5-3for additional information.
5-74

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. 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.
5-78