
Black plate (11,1)Cadillac STS Owner Manual - 2011
Limited-Slip Rear Axle
Vehicles with a limited-slip rear axle can give more
traction on snow, mud, ice, sand or gravel. It works like
a standard axle most of the time, but when traction is
low, this feature allows the drive wheel with the most
traction to move the vehicle.
All-Wheel Drive (AWD) System
With this feature, engine power is sent to all four wheels
at all times. It is fully automatic, and adjusts itself as
needed for road conditions.
Steering
Power Steering
If power steering assist is lost because the engine stops
or the system is not functioning, the vehicle can be
steered but it will take more effort.
Speed Variable Assist Steering
The vehicle has a steering system that continuously
adjusts the effort felt when steering at all vehicle
speeds. It provides ease when parking, yet a firm,
solid feel at highway speeds.
Active Steering
All‐wheel‐drive vehicles with the Active Steering with
Enhanced StabiliTrak®option have an electronically
controlled active steering system. The active steering
system uses the steering actuator to automatically
adjust the front road wheel turning angle based on
vehicle speed and how much the steering wheel is
turned. This system reduces steering effort at low
speeds, improves steering feel at moderate speeds,
and reduces steering sensitivity at higher speeds.
During some operating conditions, the active steering
might deactivate to protect the system from damage.
You might notice that the center position of the steering
wheel is changed. Unless there is a SERVICE
STEERING SYS message, the system will return to
normal operation as soon as the condition ceases,
usually within a very short period of time.
At low speeds, the active steering system requires
less movement of the steering wheel to change vehicle
direction than the normal power steering system. Adjust
your driving accordingly.
When certain steering faults are present, the active
steering deactivates and vehicle speed might be
limited. The SERVICE STEERING SYS and SPEED
LIMITED TO XXX messages will be displayed.
5-11

Black plate (18,1)Cadillac STS Owner Manual - 2011
Before Leaving on a Long Trip
To prepare your vehicle for a long trip, consider having
it serviced by your dealer before departing.
Things to check on your own include:
.Windshield Washer Fluid:Reservoir full? Windows
clean —inside and outside?
.Wiper Blades: In good shape?
.Fuel, Engine Oil, Other Fluids: All levels checked?
.Lamps:Do they all work and are lenses clean?
.Tires:Are treads good? Are tires inflated to
recommended pressure?
.Weather and Maps: Safe to travel? Have
up-to-date maps?
Highway Hypnosis
Always be alert and pay attention to your surroundings
while driving. If you become tired or sleepy, find a safe
place to park your vehicle and rest.
Other driving tips include:
.Keep the vehicle well ventilated.
.Keep interior temperature cool.
.Keep your eyes moving —scan the road ahead
and to the sides.
.Check the rearview mirror and vehicle instruments
often.
5-18

Black plate (19,1)Cadillac STS Owner Manual - 2011
Hill and Mountain Roads
Driving on steep hills or through mountains is different
than driving on flat or rolling terrain. Tips for driving in
these conditions include:
.Keep the vehicle serviced and in good shape.
.Check all fluid levels and brakes, tires, cooling
system, and transmission.
.Going down steep or long hills, shift to a
lower gear.
{WARNING:
If you do not shift down, the brakes could get so
hot that they would not work well. You would then
have poor braking or even none going down a hill.
You could crash. Shift down to let the engine
assist the brakes on a steep downhill slope.
{WARNING:
Coasting downhill in N (Neutral) or with the
ignition off is dangerous. The brakes will have to
do all the work of slowing down and they could
get so hot that they would not work well. You
would then have poor braking or even none going
down a hill. You could crash. Always have the
engine running and the vehicle in gear when
going downhill.
.Stay in your own lane. Do not swing wide or cut
across the center of the road. Drive at speeds that
let you stay in your own lane.
.Top of hills: Be alert—something could be in your
lane (stalled car, accident).
.Pay attention to special road signs (falling rocks
area, winding roads, long grades, passing or
no-passing zones) and take appropriate action.
5-19

Black plate (21,1)Cadillac STS Owner Manual - 2011
Blizzard Conditions
Being stuck in snow can be in a serious situation. Stay
with the vehicle unless there is help nearby. If possible,
use theRoadside Service
on page 8‑8. To get help
and keep everyone in the vehicle safe:
.Turn on the Hazard Warning Flasherson
page 4‑3.
.Tie a red cloth to an outside mirror.
{WARNING:
Snow can trap engine exhaust under the vehicle.
This may cause exhaust gases to get inside.
Engine exhaust contains carbon monoxide (CO)
which cannot be seen or smelled. It can cause
unconsciousness and even death.
If the vehicle is stuck in the snow:
.Clear away snow from around the base of
your vehicle, especially any that is blocking
the exhaust pipe.
.Check again from time to time to be sure
snow does not collect there.
(Continued)
WARNING: (Continued)
.Open a window about 5 cm (two inches) on
the side of the vehicle that is away from the
wind to bring in fresh air.
.Fully open the air outlets on or under the
instrument panel.
.Adjust the Climate Control system to a setting
that circulates the air inside the vehicle and
set the fan speed to the highest setting. See
Climate Control System in the Index.
For more information about carbon monoxide, see
Engine Exhaust on page 3‑36.
Snow can trap exhaust gases under your vehicle.
This can cause deadly CO (carbon monoxide) gas
to get inside. CO could overcome you and kill you.
You cannot see it or smell it, so you might not
know it is in your vehicle. Clear away snow from
around the base of your vehicle, especially any
that is blocking the exhaust.
5-21

Black plate (29,1)Cadillac STS Owner Manual - 2011
WARNING: (Continued)
.When you carry something inside the
vehicle, secure it whenever you can.
.Do not leave a seat folded down unless
you need to.
Towing
Towing Your Vehicle
Notice:To avoid damage, the disabled vehicle
should be towed with all four wheels off the ground.
Care must be taken with vehicles that have low
ground clearance and/or special equipment.
Consult your dealer or a professional towing service if
the disabled vehicle must be towed. See Roadside
Service on page 8‑8.
To tow the vehicle behind another vehicle for
recreational purposes, such as behind a motorhome,
see “Recreational Vehicle Towing” following.
Recreational Vehicle Towing
Recreational vehicle towing means towing the vehicle
behind another vehicle–such as behind a motorhome.
The two most common types of recreational vehicle
towing are known as “dinghy towing” —towing the
vehicle with all four wheels on the ground, and “dolly
towing” — towing the vehicle with two wheels on the
ground and two wheels up on a device known as a
“dolly”.
Here are some important things to consider before
recreational vehicle towing:
.What is the towing capacity of the towing vehicle?
Be sure to read the tow vehicle manufacturer's
recommendations.
.What is the distance that will be travelled? Some
vehicles have restrictions on how far and how long
they can tow.
.Is the proper towing equipment going to be used?
See your dealer or trailering professional for
additional advice and equipment
recommendations.
.Is the vehicle ready to be towed? Just as preparing
the vehicle for a long trip, make sure the vehicle is
prepared to be towed. See Before Leaving on a
Long Trip on page 5‑18.
5-29

Black plate (38,1)Cadillac STS Owner Manual - 2011
Leaving After Parking on a Hill
1. Apply and hold the brake pedal while you:
.Start the engine
.Shift into a gear
.Release the parking brake
2. Let up on the brake pedal.
3. Drive slowly until the trailer is clear of the chocks.
4. Stop and have someone pick up and store the chocks.
Maintenance When Trailer Towing
The vehicle needs service more often when pulling a
trailer. See this manual's Maintenance Schedule or
Index for more information. Things that are especially
important in trailer operation are automatic transmission
fluid, engine oil, axle lubricant, belts, cooling system
and brake system. It is a good idea to inspect these
before and during the trip.
Check periodically to see that all hitch nuts and bolts
are tight.
Engine Cooling When Trailer Towing
The cooling system may temporarily overheat during
severe operating conditions. See Engine Overheating
on page 6‑30.
5-38

Black plate (1,1)Cadillac STS Owner Manual - 2011
Section 6 Service and Appearance Care
Service. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-4
Accessories and Modifications . . . . . . . . . . . . . . . . . . 6-4
California Proposition 65 Warning . . . . . . . . . . . . . . . 6-5
California Perchlorate Materials Requirements . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-5
Doing Your Own Service Work . . . . . . . . . . . . . . . . . . 6-5
Adding Equipment to the Outside of the Vehicle . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-6
Fuel . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-6
Gasoline Octane . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-6
Gasoline Specifications . . . . . . . . . . . . . . . . . . . . . . . . . 6-7
California Fuel . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-7
Additives . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-7
Fuels in Foreign Countries . . . . . . . . . . . . . . . . . . . . . . 6-8
Filling the Tank . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-9
Filling a Portable Fuel Container . . . . . . . . . . . . . . . 6-11
Checking Things Under the Hood . . . . . . . . . . . . . . .6-12
Hood Release . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-12
Engine Compartment Overview . . . . . . . . . . . . . . . . 6-13
Engine Oil . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-16
Engine Oil Life System . . . . . . . . . . . . . . . . . . . . . . . . 6-20
Engine Air Cleaner/Filter . . . . . . . . . . . . . . . . . . . . . . . 6-21
Automatic Transmission Fluid . . . . . . . . . . . . . . . . . . 6-23
Cooling System . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-24
Engine Coolant . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-25
Engine Overheating . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-30 Overheated Engine Protection
Operating Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-32
Power Steering Fluid . . . . . . . . . . . . . . . . . . . . . . . . . . 6-33
Windshield Washer Fluid . . . . . . . . . . . . . . . . . . . . . . 6-34
Brakes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-35
Battery . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-38
Jump Starting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-38
All-Wheel Drive . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-43
Rear Axle . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-44
Front Axle . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-45
Headlamp Aiming . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-46
Bulb Replacement . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-47
High Intensity Discharge (HID) Lighting . . . . . . . . 6-47
Halogen Bulbs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-47
Back-Up Lamps . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-48
Replacement Bulbs . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-48
Windshield Replacement . . . . . . . . . . . . . . . . . . . . . . . . .6-48
Windshield Wiper Blade Replacement . . . . . . . . . . .6-49
Tires . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-50
Winter Tires . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-51
Tire Sidewall Labeling . . . . . . . . . . . . . . . . . . . . . . . . . 6-52
Tire Terminology and Definitions . . . . . . . . . . . . . . . 6-55
Inflation - Tire Pressure . . . . . . . . . . . . . . . . . . . . . . . . 6-58
High-Speed Operation . . . . . . . . . . . . . . . . . . . . . . . . . 6-60
6-1

Black plate (2,1)Cadillac STS Owner Manual - 2011
Section 6 Service and Appearance Care
Tire Pressure Monitor System . . . . . . . . . . . . . . . . . 6-60
Tire Pressure Monitor Operation . . . . . . . . . . . . . . . 6-62
Tire Inspection and Rotation . . . . . . . . . . . . . . . . . . . 6-65
When It Is Time for New Tires . . . . . . . . . . . . . . . . . 6-67
Buying New Tires . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-67
Different Size Tires and Wheels . . . . . . . . . . . . . . . 6-70
Uniform Tire Quality Grading . . . . . . . . . . . . . . . . . . . 6-71
Wheel Alignment and Tire Balance . . . . . . . . . . . . 6-72
Wheel Replacement . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-72
Tire Chains . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-74
If a Tire Goes Flat . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-74
Tire Sealant and Compressor Kit (WithoutSelector Switch) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-76
Tire Sealant and Compressor Kit (With Selector Switch) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-85
Tire Sealant and Compressor Kit Storage . . . . . . 6-94
Changing a Flat Tire . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-94
Removing the Spare Tire and Tools . . . . . . . . . . . . 6-96
Removing the Flat Tire and Installing the Spare Tire . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-97
Storing a Flat or Spare Tire and Tools . . . . . . . . 6-103
Compact Spare Tire . . . . . . . . . . . . . . . . . . . . . . . . . . 6-105 Appearance Care
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-106
Interior Cleaning . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-106
Fabric/Carpet . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-107
Leather . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-108
Instrument Panel, Vinyl, and Other Plastic Surfaces . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-108
Wood Panels . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-109
Speaker Covers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-109
Care of Safety Belts . . . . . . . . . . . . . . . . . . . . . . . . . . 6-109
Weatherstrips . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-109
Washing Your Vehicle . . . . . . . . . . . . . . . . . . . . . . . . 6-109
Cleaning Exterior Lamps/Lenses . . . . . . . . . . . . . 6-110
Finish Care . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-110
Windshield and Wiper Blades . . . . . . . . . . . . . . . . . 6-111
Aluminum or Chrome-Plated Wheels and Trim . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-112
Tires . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-113
Sheet Metal Damage . . . . . . . . . . . . . . . . . . . . . . . . . 6-113
Finish Damage . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-113
Underbody Maintenance . . . . . . . . . . . . . . . . . . . . . . 6-113
Chemical Paint Spotting . . . . . . . . . . . . . . . . . . . . . . 6-113
6-2