
Black plate (55,1)Cadillac STS Owner Manual - 2011
(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 index and speed rating of the
tire. The load index represents the load carrying
capacity a tire is certified to carry. The speed
rating is the maximum speed a tire is certified to
carry a load.
Tire Terminology and Definitions
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.
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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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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Black plate (17,1)Cadillac STS Owner Manual - 2011
To contact NHTSA, you may call the Vehicle
Safety Hotline toll-free at 1-888-327-4236
(TTY: 1-800-424-9153); go to
http://www.safercar.gov;or write to:
Administrator, NHTSA
1200 New Jersey Avenue, S.E.
Washington, D.C. 20590
You can also obtain other information about motor
vehicle safety from http://www.safercar.gov
.
Reporting Safety Defects to the
Canadian Government
If you live in Canada, and you believe that your
vehicle has a safety defect, notify Transport Canada
immediately, and notify General Motors of Canada
Limited. Call them at 1-800-333-0510 or write to:
Transport Canada
Road Safety Branch
2780 Sheffield Road
Ottawa, Ontario K1B 3V9
Reporting Safety Defects to General
Motors
In addition to notifying NHTSA (or Transport Canada) in
a situation like this, notify General Motors.
Call 1-800-458-8006, or write:Cadillac Customer Assistance Center
Cadillac Motor Car Division
P.O. Box 33169
Detroit, MI 48232-5169
In Canada, call 1‐888‐446‐2000, or write:
Canadian Cadillac Customer Communication
Centre, Mail Code: CA1-163-005
General Motors of Canada Limited
1908 Colonel Sam Drive
Oshawa, Ontario L1H 8P7
Service Publications Ordering
Information
Service Manuals
Service Manuals have the diagnosis and repair
information on the engines, transmission, axle,
suspension, brakes, electrical, steering, body, etc.
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Black plate (2,1)Cadillac STS Owner Manual - 2011
Audio System . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-94Audio Steering Wheel Controls . . . . . . . . . . . . . . . . . .4-124
Navigation/Radio System, see Navigation
Manual . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-113
Radio Personalization . . . . . . . . . . . . . . . . . . . . . . . . . . .4-120
Radio Reception . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .4-125
Setting the Clock . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-95
Theft-Deterrent Feature . . . . . . . . . . . . . . . . . . . . . . . . . .4-123
XM™ Satellite Radio Antenna System . . . . . . . . . . .4-126
Audio System(s) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-95
Automatic Transmission Fluid . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-23
Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-30
Axle, Rear . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-44
B
Back-Up Lamps - Ambulance Body Bulb Replacement . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-48
Backglass Antenna . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-126
Battery . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-38 Electric Power Management . . . . . . . . . . . . . . . . . . . . . . 4-37
Exterior Lighting Battery Saver . . . . . . . . . . . . . . . . . . . 4-35
Inadvertent Power Saver . . . . . . . . . . . . . . . . . . . . . . . . . 4-37
Load Management . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-36
Belt Routing, Engine . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-12
Bluetooth
®. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-113 Brake
Emergencies . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-6
Brakes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-35 Antilock . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-5
Parking . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-33
System Warning Light . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-58
Braking . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .5-4
Braking in Emergencies . . . . . . . . . . . . . . . . . . . . . . . . . . . . .5-6
Break-In, New Vehicle . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-25
Bulb Replacement . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-48 Back-Up Lamps - Ambulance Body . . . . . . . . . . . . . . . 6-48
Fog Lamps . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-33
Halogen Bulbs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-47
Headlamp Aiming . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-46
Headlamps . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-47
High Intensity Discharge (HID) Lighting . . . . . . . . . . . 6-47
Buying New Tires . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-67
C
Calibration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-14, 3-38
California Perchlorate Materials Requirements . . . . . . . . . . . . . . . 6-5
Warning . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-5
California Fuel . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .6-7
Canadian Owners . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . iii
Capacities and Specifications . . . . . . . . . . . . . . . . . . . . . 6-128
i - 2