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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 (36,1)Cadillac STS Owner Manual - 2011
Backing Up
Hold the bottom of the steering wheel with one hand.
Then, to move the trailer to the left, move that hand to
the left. To move the trailer to the right, move your hand
to the right. Always back up slowly and, if possible,
have someone guide you.
Making Turns
Notice:Making very sharp turns while trailering
could cause the trailer to come in contact with the
vehicle. The vehicle could be damaged. Avoid
making very sharp turns while trailering.
When turning with a trailer, make wider turns than
normal. Do this so the trailer will not strike soft
shoulders, curbs, road signs, trees or other objects.
Avoid jerky or sudden maneuvers. Signal well in
advance.
Turn Signals When Towing a Trailer
The arrows on the instrument panel flash whenever
signaling a turn or lane change. Properly hooked up,
the trailer lamps also flash, telling other drivers the
vehicle is turning, changing lanes or stopping.
When towing a trailer, the arrows on the instrument
panel flash for turns even if the bulbs on the trailer are
burned out. For this reason you may think other drivers
are seeing the signal when they are not. It is important
to check occasionally to be sure the trailer bulbs are still
working.
The vehicle has bulb warning lights. When a trailer
lighting system is plugged into the vehicle's lighting
system, its bulb warning lights may not let you know if
one of the lamps goes out. So, when the trailer lighting
system is plugged in, be sure to check the vehicle and
trailer lamps from time to time to be sure they are all
working. Once the trailer lamps are disconnected, the
bulb warning lights again can tell you if one of the
vehicle lamps is out.
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Black plate (37,1)Cadillac STS Owner Manual - 2011
Driving On Grades
Reduce speed and shift to a lower gearbeforestarting
down a long or steep downgrade. If the transmission is
not shifted down, the brakes might have to be used so
much that they would get hot and no longer work well.
On a long uphill grade, shift down and reduce the
vehicle's speed to around 45 mph (70 km/h) to reduce
the possibility of the engine and the transmission
overheating.
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.
When towing at high altitude on steep uphill grades,
consider the following: Engine coolant will boil at a
lower temperature than at normal altitudes. If the engine
is turned off immediately after towing at high altitude on
steep uphill grades, the vehicle may show signs similar
to engine overheating. To avoid this, let the engine run
while parked, preferably on level ground, with the
automatic transmission in P (Park) for a few minutes
before turning the engine off. If the overheat warning
comes on, see Engine Overheating on page 6‑30.
Parking on Hills
{WARNING:
Parking the vehicle on a hill with the trailer
attached can be dangerous. If something goes
wrong, the rig could start to move. People can be
injured, and both the vehicle and the trailer can be
damaged. When possible, always park the rig on
a flat surface.
If parking the rig on a hill: 1. Press the brake pedal, but do not shift into P (Park) yet. Turn the wheels into the curb if facing downhill
or into traffic if facing uphill.
2. Have someone place chocks under the trailer wheels.
3. When the wheel chocks are in place, release the regular brakes until the chocks absorb the load.
4. Reapply the brake pedal. Then apply the parking brake and shift into P (Park).
5. Release the brake pedal.
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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.
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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
6-2