2011 CADILLAC STS tire size

Black plate (60,1)Cadillac STS Owner Manual - 2011
High-Speed Operation
{WARNING:
Driving at high speeds, 160 km/h (100 mph) 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
inflation 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 inflation pressure for the
vehicle load.
If you will be driving at high speeds, speeds of 100 mph
(160 km/h) or higher, where it is legal, set the cold
inflation pressure to the maximum inflation pressure
shown on the tire sidewall, or 38 psi (265 kPa),
whichever is lower. See the example following. When
you end this high-speed driving, return the tires to the
cold inflation pressure shown on the Tire and Loading
Information label. See Loading the Vehicle
on
page 5‑23. Example:
You will find the maximum load and inflation pressure
molded on the tire's sidewall, in small letters, near the
rim flange. 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 inflation pressure
for high‐speed driving at 38 psi (265 kPa).
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 inflated to the inflation
pressure recommended by the vehicle manufacturer on
the vehicle placard or tire inflation pressure label. (If
your vehicle has tires of a different size than the size
indicated on the vehicle placard or tire inflation pressure
label, you should determine the proper tire inflation
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 significantly under‐inflated.
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Black plate (62,1)Cadillac STS Owner Manual - 2011
Tire Pressure Monitor Operation
This vehicle may have a Tire Pressure Monitor System
(TPMS). The TPMS is designed to warn the driver when
a low tire pressure condition exists. TPMS sensors are
mounted onto each tire and wheel assembly, excluding
the spare tire and wheel assembly, if the vehicle has
one. The TPMS sensors monitor the air pressure in the
vehicle's tires and transmits the tire pressure readings
to a receiver located in the vehicle.
When a low tire pressure
condition is detected, the
TPMS illuminates the low
tire pressure warning light
located on the instrument
panel cluster.
If the warning light comes on, stop as soon as possible
and inflate the tires to the recommended pressure
shown on the tire loading information label. See
Loading the Vehicle on page 5‑23.
At the same time a message to check the pressure in a
specific 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 inflated to the correct inflation
pressure. Using the DIC, tire pressure levels can be viewed by the driver. For additional information and
details about the DIC operation and displays see
DIC
Operation and Displays
on page 4‑70and DIC
Warnings and Messages on page 4‑76.
The low tire pressure warning light may come on in cool
weather when the vehicle is first 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 inflated 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 inflation pressure for
your vehicle's tires when they are cold. See Loading the
Vehicle
on page 5‑23for an example of the Tire and
Loading Information label and its location on your
vehicle. Also see Inflation - Tire Pressure
on
page 6‑58.
Your vehicle's TPMS can warn you about a low tire
pressure condition but it does not replace normal tire
maintenance. See Tire Inspection and Rotation
on
page 6‑65and Tires on page 6‑50.
Notice: Using non‐approved tire sealants could
damage the Tire Pressure Monitor System (TPMS)
sensors. TPMS sensor damage caused by using an
incorrect tire sealant is not covered by the vehicle
warranty. Always use the GM approved tire sealant
available through your dealer.
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Black plate (65,1)Cadillac STS Owner Manual - 2011
10. After hearing the confirming single horn chirp forthe driver side rear tire, a double horn chirp will
sound to signal the tire matching mode is no longer
active. Press the push‐button ignition switch
to Acc.
11. Set all four tires to the recommended air pressure level as indicated on the tire and loading
information label.
12. Put the valve caps back on the valve stems.
Tire Inspection and Rotation
We recommend that you regularly inspect your
vehicle's tires, including the spare tire, for signs of
wear or damage. See When It Is Time for New
Tires
on page 6‑67for more information.
Always remove the 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.
Tire rotation is not recommended if your vehicle
has P235/50ZR18 size tires on the front wheels
and P255/45ZR18 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 the 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 12 000 km (7,500 miles). See
Scheduled Maintenance
on page 7‑3.
The purpose of a regular tire rotation is to achieve
a uniform wear for all tires on the vehicle. This will
ensure that the vehicle continues to perform most
like it did when the tires were new.
Any time you notice unusual wear, rotate your
tires as soon as possible and check wheel
alignment. Also check for damaged tires or
wheels. See When It Is Time for New Tires
on
page 6‑67
and Wheel Replacementon page 6‑72.
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Black plate (66,1)Cadillac STS Owner Manual - 2011
When rotating P235/50R17 size tires or
255/45ZR18 size tires, always use the correct
rotation pattern shown here.
If the 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 inflation pressures as shown on the Tire
and Loading Information label. SeeInflation - Tire
Pressure
on page 6‑58and Loading the Vehicleon
page 5‑23
.
Reset the Tire Pressure Monitor System. See Tire
Pressure Monitor Operation
on page 6‑62. Make certain that all wheel nuts are properly
tightened. See
“Wheel Nut Torque” under
Capacities and Specifications
on page 6‑128.
{WARNING:
Rust or dirt on a wheel, or on the parts to
which it is fastened, can make wheel nuts
become loose after 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. See
Changing a Flat Tire
on page 6‑94.
Lightly coat the center of the wheel hub with
wheel bearing grease after a wheel change or tire
rotation to prevent corrosion or rust build-up. Do
not get grease on the flat wheel mounting surface
or on the wheel nuts or bolts.
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Black plate (68,1)Cadillac STS Owner Manual - 2011
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 specifications 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 6‑52
for additional information.
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.
{WARNING:
Tires could explode during improper service. You
or others could be injured or killed if you attempt
to mount or dismount a tire. Only your dealer or
an authorized tire service center should mount
and dismount the tires.
The optional 18‐inch performance tires, size
255/45ZR18 99Y, used on some vehicles, meets
the General Motors Tire Performance Criteria
Specification (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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Black plate (69,1)Cadillac STS Owner Manual - 2011
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
snow tires with a lower speed rating, never
exceed the tire's maximum speed capability.
{WARNING:
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. SeeCompact Spare Tire on page 6‑105.
{WARNING:
If you use bias-ply tires on the vehicle, the
wheel rim flanges 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 the
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 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. See Tire Pressure Monitor
System
on page 6‑60.
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Black plate (70,1)Cadillac STS Owner Manual - 2011
Your vehicle's original equipment tires are listed
on the Tire and Loading Information label. See
Loading the Vehicle
on page 5‑23, 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.
{WARNING:
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 specific wheel and tire
systems developed for your vehicle, and have
them properly installed by a GM certified
technician.
See Buying New Tires
on page 6‑67andAccessories
and Modificationson page 6‑4for additional
information.
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Black plate (74,1)Cadillac STS Owner Manual - 2011
Tire Chains
{WARNING:
If your vehicle has P255/45R17, P255/45ZR18,
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 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 your
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 find traction devices that will fit, install
them on the rear tires only.Notice:
If your vehicle has P235/50R17 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.
If a Tire Goes Flat
It is unusual for a tire to blowout while you are driving,
especially if you maintain your vehicle's tires properly.
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 flat tire creates a drag that pulls
the vehicle toward that side. Take your foot off the
accelerator pedal and grip the steering wheel firmly.
Steer to maintain lane position, and then gently brake to
a stop, well off the road, if possible.
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