2008 CADILLAC STS Tires

Do not tow a trailer at all during the rst 1,000 miles
(1 600 km) your new vehicle is driven. Your engine,
axle or other parts could be damaged.
Then, during the rst 500 miles (800 km) that you
tow a trailer, do not drive over 50 mph (80 km/h)
and do not make starts at full throttle. This
helps your engine and other parts of your vehicle
wear in at the heavier loads.
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 your vehicle’s parts.
Three important considerations have to do with weight:
The weight of the trailer.
The weight of the trailer tongue.
The total weight on your 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 you plan to use your rig. For
example, speed, altitude, road grades, outside
temperature and how much your vehicle is used to pull
a trailer are all important. It can also depend on any
special equipment that you have on your 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 form the maximum trailer weight.
You can ask your dealer/retailer for our trailering
information or advice, or you can write us at our
Customer Assistance Offices. SeeCustomer Assistance
Offices on page 7-5for more information.
4-35

Weight of the Trailer Tongue
The tongue load (A) of any trailer is an important weight
to measure because it affects the total or gross weight
of your vehicle. The Gross Vehicle Weight (GVW)
includes the curb weight of the vehicle, any cargo you
may carry in it, and the people who will be riding in
the vehicle. If you have a lot of options, equipment,
passengers, or cargo in your vehicle, it will reduce the
tongue weight your vehicle can carry, which will also
reduce the trailer weight your vehicle can tow. And if you
tow a trailer, you must add the tongue load to the
GVW because your vehicle will be carrying that weight,
too. SeeLoading Your Vehicle on page 4-26for
more information about your vehicle’s maximum load
capacity.If you are using a weight-carrying hitch, the trailer
tongue (A) should weigh 10 to 15 percent of the total
loaded trailer weight (B).
After you have loaded your trailer, weigh the trailer and
then the tongue, separately, to see if the weights are
proper. If they are not, you may be able to get them right
simply by moving some items around in the trailer.
Total Weight on Your Vehicle’s Tires
Be sure your vehicle’s tires are inated to the upper limit
for cold tires. You will nd these numbers on the
Tire-Loading Information label. SeeLoading Your
Vehicle on page 4-26. Then be sure you do not go over
the GVW limit for your vehicle, including the weight
of the trailer tongue.
4-36

Driving with a Trailer
Towing a trailer requires a certain amount of experience.
Before setting out for the open road, you will want to
get to know your rig. Acquaint yourself 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 a good deal longer and not nearly as
responsive as your vehicle is by itself.
Before you start, check all trailer hitch parts and
attachments, safety chains, electrical connector, lamps,
tires and mirror adjustment. If the trailer has electric
brakes, start your vehicle and trailer moving and then
apply the trailer brake controller by hand to be sure
the brakes are working. This lets you check your
electrical connection at the same time.
During your 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 your vehicle without a trailer.
This can help you avoid situations that require
heavy braking and sudden turns.
Passing
You will need more passing distance up ahead when
you are towing a trailer. And, because the vehicle
is a good deal longer, you will need to go much farther
beyond the passed vehicle before you can return to
your lane.
Backing Up
Hold the bottom of the steering wheel with one hand.
Then, to move the trailer to the left, just 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. Your vehicle could be damaged. Avoid
making very sharp turns while trailering.
When you are turning with a trailer, make wider turns
than normal. Do this so your trailer will not strike
soft shoulders, curbs, road signs, trees or other objects.
Avoid jerky or sudden maneuvers. Signal well in
advance.
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Service............................................................5-3
Accessories and Modications..........................5-3
California Proposition 65 Warning.....................5-3
California Perchlorate Materials Requirements.....5-4
Doing Your Own Service Work.........................5-4
Adding Equipment to the Outside
of Your Vehicle...........................................5-4
Fuel................................................................5-5
Gasoline Octane............................................5-5
Gasoline Specications....................................5-6
California Fuel...............................................5-6
Additives.......................................................5-6
Fuels in Foreign Countries...............................5-7
Filling the Tank..............................................5-7
Filling a Portable Fuel Container.......................5-9
Checking Things Under the Hood....................5-10
Hood Release..............................................5-10
Engine Compartment Overview.......................5-11
Engine Oil...................................................5-18
Engine Oil Life System..................................5-21
Engine Air Cleaner/Filter................................5-23
Automatic Transmission Fluid.........................5-25
Engine Coolant.............................................5-25
Coolant Surge Tank Pressure Cap..................5-29
Engine Overheating.......................................5-29
Overheated Engine Protection Operating Mode . . .5-31Cooling System............................................5-32
Power Steering Fluid.....................................5-39
Windshield Washer Fluid................................5-40
Brakes........................................................5-41
Battery........................................................5-44
Jump Starting...............................................5-45
All-Wheel Drive..............................................5-50
Rear Axle.......................................................5-51
Front Axle......................................................5-52
Headlamp Aiming...........................................5-53
Bulb Replacement..........................................5-54
High Intensity Discharge (HID) Lighting............5-54
Halogen Bulbs..............................................5-54
Back-Up Lamps............................................5-54
Replacement Bulbs.......................................5-55
Windshield Replacement.................................5-55
Windshield Wiper Blade Replacement..............5-55
Tires..............................................................5-57
Winter Tires.................................................5-58
Tire Sidewall Labeling...................................5-59
Tire Terminology and Denitions.....................5-62
Run-Flat Tires (STS-V)..................................5-65
Ination - Tire Pressure.................................5-66
High-Speed Operation...................................5-68
Section 5 Service and Appearance Care
5-1

Tire Pressure Monitor System.........................5-68
Tire Pressure Monitor Operation.....................5-70
Tire Inspection and Rotation...........................5-73
When It Is Time for New Tires.......................5-75
Buying New Tires.........................................5-76
Different Size Tires and Wheels......................5-78
Uniform Tire Quality Grading..........................5-79
Wheel Alignment and Tire Balance..................5-80
Wheel Replacement......................................5-80
Tire Chains..................................................5-82
Lifting Your Vehicle (STS-V)...........................5-83
If a Tire Goes Flat........................................5-86
Tire Sealant and Compressor Kit....................5-87
Changing a Flat Tire.....................................5-96
Removing the Spare Tire and Tools................5-98
Removing the Flat Tire and Installing
the Spare Tire..........................................5-99
Storing a Flat or Spare Tire and Tools...........5-104
Compact Spare Tire....................................5-106
Appearance Care..........................................5-107
Interior Cleaning.........................................5-107
Fabric/Carpet..............................................5-108
Leather......................................................5-109
Instrument Panel, Vinyl, and Other
Plastic Surfaces.......................................5-109
Wood Panels..............................................5-110Speaker Covers..........................................5-110
Care of Safety Belts....................................5-110
Weatherstrips.............................................5-110
Washing Your Vehicle..................................5-110
Cleaning Exterior Lamps/Lenses....................5-111
Finish Care................................................5-111
Windshield and Wiper Blades.......................5-112
Aluminum or Chrome-Plated Wheels and Trim . . .5-112
Tires.........................................................5-113
Sheet Metal Damage...................................5-113
Finish Damage...........................................5-114
Underbody Maintenance...............................5-114
Chemical Paint Spotting...............................5-114
Vehicle Care/Appearance Materials................5-115
Vehicle Identication.....................................5-116
Vehicle Identication Number (VIN)................5-116
Service Parts Identication Label...................5-116
Electrical System..........................................5-116
Add-On Electrical Equipment.........................5-116
Headlamp Wiring........................................5-117
Windshield Wiper Fuses...............................5-117
Power Windows and Other Power Options......5-117
Fuses and Circuit Breakers..........................5-117
Underhood Fuse Block................................5-118
Rear Underseat Fuse Block..........................5-121
Capacities and Specications........................5-128
Section 5 Service and Appearance Care
5-2

Brake Wear
Your vehicle has disc brakes. Disc brake pads have
built-in wear indicators that make a high-pitched warning
sound when the brake pads are worn and new pads
are needed. The sound can come and go or be heard all
the time your vehicle is moving, except when you are
pushing on the brake pedal rmly.
{CAUTION:
The brake wear warning sound means that
soon the brakes will not work well. That could
lead to an accident. When you hear the brake
wear warning sound, have your 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 rst 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 specications in
Capacities and Specifications on page 5-128.
Brake linings should always be replaced as complete
axle sets.Brake Pedal Travel
See your dealer/retailer 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 you apply the brakes, with or without the
vehicle moving, the brakes adjust for wear.
5-43

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.
{CAUTION:
Poorly maintained and improperly
used tires are dangerous.
Overloading your tires can cause
overheating as a result of too much
exing. You could have an air-out and
a serious accident. SeeLoading Your
Vehicle on page 4-26.
CAUTION: (Continued)
CAUTION: (Continued)

Underinated tires pose the same
danger as overloaded tires. The
resulting accident could cause serious
injury. Check all tires frequently to
maintain the recommended pressure.
Tire pressure should be checked when
your tires are cold. SeeInflation - Tire
Pressure on page 5-66.
Overinated 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, old tires can cause accidents.
If your tread is badly worn, or if
your tires have been damaged,
replace them.
SeeHigh-Speed Operation on page 5-68
for ination pressure adjustment for high
speed driving.
5-57

Low-Prole Performance Tires
If your vehicle has 255/45ZR18, P255/45R18 or
P275/40R19 size tires, they are classied as
low-prole performance tires. These tires are
designed for very responsive driving on wet or dry
pavement. You may also notice more road noise
with low-prole 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 your vehicle has low-prole tires,
they are more susceptible to damage from road
hazards or curb impact than standard prole
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. Your
vehicle warranty does not cover this type of
damage. Keep tires set to the correct ination
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/retailer for details regarding winter tire
availability and proper tire selection. Also, seeBuying
New Tires on page 5-76.
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.
5-58