
Black plate (32,1)Cadillac STS Owner Manual - 2011
Trailering is different than just driving the vehicle
by itself. Trailering means changes in handling,
acceleration, braking, durability and fuel economy.
Successful, safe trailering takes correct equipment,
and it has to be used properly.
The following information has many time-tested,
important trailering tips and safety rules. Many of
these are important for your safety and that of your
passengers. So please read this section carefully
before pulling a trailer.
Load-pulling components such as the engine,
transmission, rear axle, wheel assemblies and tires are
forced to work harder against the drag of the added
weight. The engine is required to operate at relatively
higher speeds and under greater loads, generating
extra heat. The trailer also adds considerably to wind
resistance, increasing the pulling requirements.Pulling A Trailer
Here are some important points:
.Do not tow a trailer at all during the first 500 miles
(800 km) the new vehicle is driven. The engine,
axle or other parts could be damaged.
.Then, during the first 500 miles (800 km) that a
trailer is towed, do not drive over 50 mph (80 km/h)
and do not make starts at full throttle. This helps
the engine and other parts of the vehicle wear in at
the heavier loads.
.Vehicles can tow in D (Drive). Shift the
transmission to a lower gear if the transmission
shifts too often under heavy loads and/or hilly
conditions.
.Obey speed limit restrictions when towing a trailer.
Do not drive faster than the maximum posted
speed for trailers, or no more than 55 mph
(90 km/h), to save wear on the vehicle's parts.
.If the vehicle has the Side Blind Zone Alert (SBZA)
system and it doesn't seem to be working properly
while pulling a trailer, turn the system off. SeeSide
Blind Zone Alert (SBZA)
on page 3‑44for more
information.
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Black plate (33,1)Cadillac STS Owner Manual - 2011
Three important considerations have to do with weight:
.The weight of the trailer.
.The weight of the trailer tongue.
.The total weight on the vehicle's tires.
Weight of the Trailer
How heavy can a trailer safely be?
It should never weigh more than 1,000 lbs (450 kg).
But even that can be too heavy.
It depends on how the rig is used. For example, speed,
altitude, road grades, outside temperature and how
much the vehicle is used to pull a trailer are all
important. It can depend on any special equipment on
the vehicle, and the amount of tongue weight the
vehicle can carry. See“Weight of the Trailer Tongue”
later in this section for more information.
Maximum trailer weight is calculated assuming only the
driver is in the tow vehicle and it has all the required
trailering equipment. The weight of additional optional
equipment, passengers and cargo in the tow vehicle
must be subtracted from the maximum trailer weight.
Ask your dealer for our trailering information or advice,
or write us at our Customer Assistance Offices. See
Customer Assistance Offices
on page 8‑6for more
information.
Weight of the Trailer Tongue
The tongue load (A) of any trailer is an important weight
to measure because it affects the total gross weight of
the vehicle. The Gross Vehicle Weight (GVW) includes
the curb weight of the vehicle, any cargo carried in it,
and the people who will be riding in the vehicle. If there
are a lot of options, equipment, passengers or cargo in
the vehicle, it will reduce the tongue weight the vehicle
can carry, which will also reduce the trailer weight the
vehicle can tow. If towing a trailer, the tongue load must
be added to the GVW because the vehicle will be
carrying that weight, too. See Loading the Vehicle
on
page 5‑23for more information about the vehicle's
maximum load capacity.
If using a weight-carrying hitch, the trailer tongue (A)
should weigh 10 to 15 percent of the total loaded trailer
weight (B).
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Black plate (34,1)Cadillac STS Owner Manual - 2011
After loading the trailer, weigh the trailer and then the
tongue, separately, to see if the weights are proper.
If they are not, adjustments might be made by moving
some items around in the trailer.
Total Weight on the Vehicle's Tires
Be sure the vehicle's tires are inflated to the upper
limit for cold tires. These numbers can be found on
the Certification label or seeLoading the Vehicle
on
page 5‑23. Make sure not to go over the GVW limit for
the vehicle, or the GAWR, including the weight of the
trailer tongue.
Hitches
It is important to have the correct hitch equipment.
Crosswinds, large trucks going by and rough roads
are a few reasons why the right hitch is needed.
.The rear bumper on the vehicle is not intended
for hitches. Do not attach rental hitches or
other bumper-type hitches to it. Use only a
frame-mounted hitch that does not attach to the
bumper.
.Will any holes be made in the body of the vehicle
when the trailer hitch is installed? If so, be sure to
seal the holes when the hitch is removed. If they
are not sealed, deadly carbon monoxide (CO) from
the engine's exhaust can get into the vehicle. See
Engine Exhaust
on page 3‑36. Sealing the holes
will also prevent dirt and water from entering the
vehicle.
Safety Chains
Always attach chains between the vehicle and the
trailer. Cross the safety chains under the tongue of the
trailer to help prevent the tongue from contacting the
road if it becomes separated from the hitch. Instructions
about safety chains may be provided by the hitch
manufacturer or by the trailer manufacturer. Follow the
manufacturer's recommendation for attaching safety
chains and do not attach them to the bumper. Always
leave just enough slack so the rig can turn. Never allow
safety chains to drag on the ground.
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Black plate (35,1)Cadillac STS Owner Manual - 2011
Trailer Brakes
Does the trailer have its own brakes? Be sure to
read and follow the instructions for the trailer brakes so
they are installed, adjusted and maintained properly.
Because the vehicle has StabiliTrak
®, do not try to tap
into the vehicle's hydraulic brake system. If you do, both
brake systems will not work well, or at all.
Trailer Wiring Harness
All of the electrical circuits required for the trailer lighting
system can be accessed at the driver side rear lamp
connector. This connector is located under the carpet
on the rear corner of the trunk compartment.
Driving with a Trailer
Towing a trailer requires a certain amount of
experience. Get to know the rig before setting out
for the open road. Get acquainted with the feel of
handling and braking with the added weight of the
trailer. And always keep in mind that the vehicle you
are driving is now longer and not as responsive as the
vehicle is by itself. Before starting, check all trailer hitch parts and
attachments, safety chains, electrical connectors,
lamps, tires and mirror adjustments. If the trailer has
electric brakes, start the vehicle and trailer moving and
then apply the trailer brake controller by hand to be sure
the brakes are working. This checks the electrical
connection at the same time.
During the trip, check occasionally to be sure that the
load is secure, and that the lamps and any trailer
brakes are still working.
Following Distance
Stay at least twice as far behind the vehicle ahead as
you would when driving the vehicle without a trailer.
This can help to avoid situations that require heavy
braking and sudden turns.
Passing
More passing distance is needed when towing a trailer.
Because the rig is longer, it is necessary to go much
farther beyond the passed vehicle before returning to
the lane.
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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
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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
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Black plate (37,1)Cadillac STS Owner Manual - 2011
{WARNING:
The brake wear warning sound means that soon
the brakes will not work well. That could lead to a
crash. When the brake wear warning sound is
heard, have the vehicle serviced.
Notice: Continuing to drive with worn-out brake
pads could result in costly brake repair.
Some driving conditions or climates can cause a brake
squeal when the brakes are first applied or lightly
applied. This does not mean something is wrong with
the brakes.
Properly torqued wheel nuts are necessary to help
prevent brake pulsation. When tires are rotated, inspect
brake pads for wear and evenly tighten wheel nuts in
the proper sequence to torque specifications in
Capacities and Specifications on page 6‑128.
Brake linings should always be replaced as complete
axle sets.
Brake Pedal Travel
See your dealer if the brake pedal does not return to
normal height, or if there is a rapid increase in pedal
travel. This could be a sign that brake service might be
required.
Brake Adjustment
Every time the brakes are applied, with or without the
vehicle moving, the brakes adjust for wear.
Replacing Brake System Parts
The braking system on a vehicle is complex. Its many
parts have to be of top quality and work well together if
the vehicle is to have really good braking. The vehicle
was designed and tested with top-quality brake parts.
When parts of the braking system are replaced —for
example, when the brake linings wear down and new
ones are installed —be sure to get new approved
replacement parts. If this is not done, the brakes might
not work properly. For example, if someone puts in
brake linings that are wrong for the vehicle, the balance
between the front and rear brakes can change —for the
worse. The braking performance expected can change
in many other ways if the wrong replacement brake
parts are installed.
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Black plate (50,1)Cadillac STS Owner Manual - 2011
Tires
Your new vehicle comes with high-quality tires
made by a leading tire manufacturer. If you ever
have questions about your tire warranty and
where to obtain service, see your vehicle
Warranty booklet for details. For additional
information refer to the tire manufacturer.
{WARNING:
.Poorly maintained and improperly used tires
are dangerous.
.Overloading your tires can cause overheating
as a result of too much flexing. You could
have a blowout and a serious accident. See
Loading the Vehicle on page 5‑23.
.Under inflated tires pose the same danger as
overloaded tires. The resulting crash could
cause serious injury. Check all tires frequently
to maintain the recommended pressure. Tire
pressure should be checked when your tires
are cold.(Continued)
WARNING: (Continued)
.Over inflated tires are more likely to be
cut, punctured, or broken by a sudden
impact—such as when you hit a pothole.
Keep tires at the recommended pressure.
.Worn or old tires can cause a crash. If your
tread is badly worn, replace them.
.Replace any tires that have been damaged by
impacts with potholes, curbs, etc.
.Improperly repaired tires can cause a crash.
Only your dealer or an authorized tire service
center should repair, replace, dismount, and
mount the tires.
.Do not spin the tires in excess of 55 km/h
(35 mph) on slippery surfaces such as snow,
mud, ice, etc. Excessive spinning may cause
the tires to explode.
See High-Speed Operation
on page 6‑60for inflation
pressure adjustment for high speed driving.
6-50