
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 (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 (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.
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Black plate (51,1)Cadillac STS Owner Manual - 2011
Low‐Profile Performance Tires
If your vehicle has 255/45ZR18 size tires, they are
classified as low‐profile performance tires. These
tires are designed for very responsive driving on
wet or dry pavement. You may also notice more
road noise with low‐profile performance tires and
that they tend to wear faster. These performance
tires are not rated as all‐season tires. Winter tires
are recommended for snow or ice covered roads.
Notice:If the vehicle has low‐profile tires, they
are more susceptible to damage from road
hazards or curb impact than standard profile
tires. Tire and/or wheel assembly damage can
occur when coming into contact with road
hazards like, potholes, or sharp edged objects,
or when sliding into a curb. The vehicle
warranty does not cover this type of damage.
Keep tires set to the correct inflation pressure
and, when possible avoid contact with curbs,
potholes, and other road hazards.
Winter Tires
If you expect to drive on snow or ice covered roads
often, you may want to get winter tires for your vehicle.
All season tires provide good overall performance on
most surfaces but they may not offer the traction you
would like or the same level of performance as winter
tires on snow or ice covered roads.
Winter tires, in general, are designed for increased
traction on snow and ice covered roads. With winter
tires, there may be decreased dry road traction,
increased road noise, and shorter tread life. After
switching to winter tires, be alert for changes in vehicle
handling and braking.
See your dealer for details regarding winter tire
availability and proper tire selection. Also, see Buying
New Tires on page 6‑67.
If you choose to use winter tires:
.Use tires of the same brand and tread type on all
four wheel positions.
.Use only radial ply tires of the same size, load
range, and speed rating as the original equipment
tires.
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 winter tires with a
lower speed rating, never exceed the tire's maximum
speed capability.
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Black plate (53,1)Cadillac STS Owner Manual - 2011
(E) Tire Ply Material:The type of cord and
number of plies in the sidewall and under the
tread.
(F) Uniform Tire Quality Grading (UTQG)
:Tire
manufacturers are required to grade tires based
on three performance factors: treadwear, traction,
and temperature resistance. For more information
see Uniform Tire Quality Grading
on page 6‑71.
(G) Maximum Cold Inflation Load Limit
:
Maximum load that can be carried and the
maximum pressure needed to support that load.
Compact Spare Tire Example
(A) Temporary Use Only:The compact spare
tire or temporary use tire has a tread life of
approximately 3,000 miles (5 000 km) and should
not be driven at speeds over 65 mph (105 km/h).
The compact spare tire is for emergency use
when a regular road tire has lost air and gone flat.
If your vehicle has a compact spare tire, see
Compact Spare Tire
on page 6‑105and If a Tire
Goes Flat
on page 6‑74.
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Black plate (54,1)Cadillac STS Owner Manual - 2011
(B) Tire Ply Material:The type of cord and
number of plies in the sidewall and under the
tread.
(C) Tire Identification Number (TIN)
:The letters
and numbers following the DOT (Department of
Transportation) code is the Tire Identification
Number (TIN). The TIN shows the manufacturer
and plant code, tire size, and date the tire was
manufactured. The TIN is molded onto both sides
of the tire, although only one side may have the
date of manufacture.
(D) Maximum Cold Inflation Load Limit
:
Maximum load that can be carried and the
maximum pressure needed to support that load.
(E) Tire Inflation
:The temporary use tire or
compact spare tire should be inflated to 60 psi
(420 kPa). For more information on tire pressure
and inflation see Inflation - Tire Pressure
on
page 6‑58
.
(F) Tire Size
:A combination of letters and
numbers define a tire's width, height, aspect ratio,
construction type, and service description. The
letter T as the first character in the tire size means
the tire is for temporary use only. (G) TPC Spec (Tire Performance Criteria
Specification)
:Original equipment tires designed
to GM's specific tire performance criteria have a
TPC specification code molded onto the sidewall.
GM's TPC specifications meet or exceed all
federal safety guidelines.
Tire Size
The following illustration shows an example of a
typical passenger vehicle tire size.
(A) Passenger (P‐Metric) Tire:The United States
version of a metric tire sizing system. The letter P
as the first character in the tire size means a
passenger vehicle tire engineered to standards
set by the U.S. Tire and Rim Association.
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Black plate (56,1)Cadillac STS Owner Manual - 2011
Cold Tire Pressure:The amount of air pressure
in a tire, measured in pounds per square inch (psi)
or kilopascals (kPa) before a tire has built up heat
from driving. See Inflation - Tire Pressure
on
page 6‑58
.
Curb Weight
:The weight of a motor vehicle with
standard and optional equipment including the
maximum capacity of fuel, oil, and coolant, but
without passengers and cargo.
DOT Markings
:A code molded into the sidewall
of a tire signifying that the tire is in compliance
with the U.S. Department of Transportation (DOT)
motor vehicle safety standards. The DOT code
includes the Tire Identification Number (TIN), an
alphanumeric designator which can also identify
the tire manufacturer, production plant, brand, and
date of production.
GVWR
:Gross Vehicle Weight Rating. See
Loading the Vehicle
on page 5‑23.
GAWR FRT
:Gross Axle Weight Rating for the
front axle. See Loading the Vehicle
on page 5‑23.
GAWR RR
:Gross Axle Weight Rating for the rear
axle. See Loading the Vehicle
on page 5‑23. Intended Outboard Sidewall
:The side of an
asymmetrical tire, that must always face outward
when mounted on a vehicle.
Kilopascal (kPa)
:The metric unit for air pressure.
Light Truck (LT‐Metric) Tire
:A tire used on light
duty trucks and some multipurpose passenger
vehicles.
Load Index
:An assigned number ranging
from 1 to 279 that corresponds to the load
carrying capacity of a tire.
Maximum Inflation Pressure
:The maximum air
pressure to which a cold tire can be inflated. The
maximum air pressure is molded onto the
sidewall.
Maximum Load Rating
:The load rating for a tire
at the maximum permissible inflation pressure for
that tire.
Maximum Loaded Vehicle Weight
:The sum of
curb weight, accessory weight, vehicle capacity
weight, and production options weight.
Normal Occupant Weight
:The number of
occupants a vehicle is designed to seat multiplied
by 150 lbs (68 kg). See Loading the Vehicle
on
page 5‑23
.
6-56