2006 CADILLAC STS spare tire

Tire Inspection and Rotation
Tire rotation is not recommended if your vehicle has the
following performance tire combinations:
P235/50R17 size tires on the front wheels and
P255/45R17 size tires on the rear wheels.
P235/50R18 size tires on the front wheels and
P255/45R18 size tires on the rear wheels.
P255/45R18 size tires on the front wheels and
P275/40R19 size tires on the rear wheels.
Different tire sizes should not be rotated front to rear.
Each tire and wheel should only be used in the original
front or rear position it is in.
Tire rotation is recommended if your vehicle is equipped
with P235/50R17 size tires on all four wheel positions
or 255/45ZR18 size tires on all four wheel positions.
These tires should be rotated every 5,000 to 8,000 miles
(8 000 to 13 000 km)
Any time you notice unusual wear, rotate your tires as
soon as possible and check wheel alignment. Also
check for damaged tires or wheels. SeeWhen It Is Time
for New Tires on page 5-71andWheel Replacement
on page 5-76for more information.The purpose of regular rotation is to achieve more
uniform wear for all tires on the vehicle. The rst rotation
is the most important. SeeScheduled Maintenance
on page 6-4.
When rotating P235/50R17 size tires or 255/45ZR18
size tires, always use the correct rotation pattern
shown here.
If your vehicle has a compact spare tire, do not include
the compact spare tire in the tire rotation.
After the tires have been rotated, adjust the front and
rear ination pressures as shown on the Tire and
Loading Information label.
5-70

{CAUTION:
Mixing tires could cause you to lose control
while driving. If you mix tires of different sizes
(other than those originally installed on
your vehicle), brands, or types (radial and
bias-belted tires), the vehicle may not handle
properly, and you could have a crash. Using
tires of different sizes (other than those
originally installed on your vehicle), brands, or
types may also cause damage to your vehicle.
Be sure to use the correct size, brand, and
type of tires on all wheels. It is all right to drive
with your vehicle’s compact spare temporarily,
it was developed for use on your vehicle. See
Compact Spare Tire (STS Only) on page 5-94.
{CAUTION:
If you use bias-ply tires on your vehicle, the
wheel rim anges could develop cracks after
many miles of driving. A tire and/or wheel
could fail suddenly, causing a crash. Use only
radial-ply tires with the wheels on your vehicle.
If you must replace your vehicle’s tires with those that
do not have a TPC Spec number, make sure they
are the same size, load range, speed rating, and
construction type (radial and bias-belted tires) as your
vehicle’s original tires.
5-73

Uniform Tire Quality Grading
Quality grades can be found where applicable on the
tire sidewall between tread shoulder and maximum
section width. For example:
Treadwear 200 Traction AA Temperature A
The following information relates to the system
developed by the United States National Highway
Traffic Safety Administration (NHTSA), which grades
tires by treadwear, traction, and temperature
performance. This applies only to vehicles sold in the
United States. The grades are molded on the sidewalls
of most passenger car tires. The Uniform Tire Quality
Grading (UTQG) system does not apply to deep
tread, winter-type snow tires, space-saver, or temporary
use spare tires, tires with nominal rim diameters of
10 to 12 inches (25 to 30 cm), or to some
limited-production tires.
While the tires available on General Motors passenger
cars and light trucks may vary with respect to these
grades, they must also conform to federal safety
requirements and additional General Motors Tire
Performance Criteria (TPC) standards.
Treadwear
The treadwear grade is a comparative rating based on
the wear rate of the tire when tested under controlled
conditions on a specied government test course.
For example, a tire graded 150 would wear one and
a half (1.5) times as well on the government course as
a tire graded 100. The relative performance of tires
depends upon the actual conditions of their use,
however, and may depart signicantly from the norm
due to variations in driving habits, service practices,
and differences in road characteristics and climate.
Traction – AA, A, B, C
The traction grades, from highest to lowest, are AA,
A, B, and C. Those grades represent the tire’s ability to
stop on wet pavement as measured under controlled
conditions on specied government test surfaces
of asphalt and concrete. A tire marked C may have
poor traction performance.
Warning:The traction grade assigned to this tire is
based on straight-ahead braking traction tests, and
does not include acceleration, cornering, hydroplaning,
or peak traction characteristics.
5-75

If a tire goes at, and your vehicle has a spare tire, see
Changing a Flat Tire (STS Only) on page 5-83. This
information shows you how to use your vehicle’s tire
changing equipment and how to change a at tire safely.
{CAUTION:
Lifting a vehicle and getting under it to do
maintenance or repairs is dangerous without
the appropriate safety equipment and training.
The jack provided with your vehicle is
designed only for changing a at tire. If it is
used for anything else, you or others could be
badly injured or killed if the vehicle slips off
the jack. Use the jack provided with your
vehicle only for changing a at tire.
Run-Flat Tires (STS-V)
If your vehicle has run-at tires, there is no spare tire
and no tire changing equipment. Run-at tires can
operate effectively with no air pressure for a limited
distance and speed. Your vehicle also has a Tire
Pressure Monitor (TPM) which will alert you if there
is a loss of tire pressure in any of the tires. These
tires perform so well without any air pressure that a
Tire Pressure Monitor (TPM) is used to alert you when
there is a low tire condition.
{CAUTION:
When the low tire warning light is displayed on
the instrument panel cluster, your vehicle’s
handling capabilities will be reduced during
severe maneuvers. If you drive too fast, you
could lose control of your vehicle. You or
others could be injured. Do not drive over
55 mph (90 km/h) when the low tire warning
light is displayed. Drive cautiously and check
your tire pressures as soon as you can.
5-82

SeeRun-Flat Tires (STS-V) on page 5-63andTire
Pressure Monitor System on page 5-66, for additional
information.
{CAUTION:
Special tools and procedures are required to
service a run-at tire. If these special tools
and procedures are not used you or others
could be injured and your vehicle could be
damaged. Always be sure the proper tools
and procedures, as described in the service
manual, are used.
To order a service manual seeService Publications
Ordering Information on page 7-14.
Changing a Flat Tire (STS Only)
If you have an STS-V model, there is no spare tire and
no tire changing equipment. Your vehicle is equipped
with run-at tires. SeeRun-Flat Tires (STS-V) on
page 5-63for more information. If you have an STS
model, follow the directions for changing a at tire in
this section.
If a tire goes at, avoid further tire and wheel damage
by driving slowly to a level place. Turn on your vehicle’s
hazard warning ashers. SeeHazard Warning Flashers
on page 3-6for more information.
5-83

Removing the Spare Tire and Tools
(STS Only)
The equipment you will need is located in the trunk.
To gain access to the compact spare tire and jacking
equipment, do the following:
1. Open the trunk. SeeTrunk on page 2-14for more
information.
2. Remove the compact spare tire cover.
3. Turn the nut holding the jack package container
counterclockwise and remove it. Then remove the
jack and wheel wrench.4. Remove the compact spare tire. SeeCompact
Spare Tire (STS Only) on page 5-94for more
information about the compact spare tire.
The tools you will be using include the jack (A) and the
wheel wrench (B).
5-85

Removing the Flat Tire and
Installing the Spare Tire (STS Only)
1. If your vehicle has wheel covers, use the at end of
the wheel wrench to remove the covers. Turn the
wheel wrench clockwise to gently pry off the wheel
cover. Be careful not to scratch the aluminum wheel
edge and do not try to remove the wheel cover with
your hands.2. Loosen the wheel nuts, but do not remove them
yet, using the wheel wrench. Turn the handle
about 180 degrees, then ip the handle back to the
starting position. This avoids taking the wrench
off the lug nut for each turn.
5-86

{CAUTION:
Lifting a vehicle and getting under it to do
maintenance or repairs is dangerous without
the appropriate safety equipment and training.
The jack provided with your vehicle is
designed only for changing a at tire. If it is
used for anything else, you or others could be
badly injured or killed if the vehicle slips off
the jack. Use the jack provided with your
vehicle only for changing a at tire.
Notice:If you position the jack under the rocker
molding and attempt to raise the vehicle, you could
break the molding and/or cause other damage to
your vehicle. Always position the jack so that when
the jack head is raised, it will t rmly in the
notch located inboard from the rocker molding.
5. Turn the wheel wrench counterclockwise to lower
the jack lift head until the jack ts under the
vehicle.6. Raise the jack by turning the wheel wrench
clockwise until the slots in the jack head t into the
metal ange located behind the triangle on the
plastic molding as shown.
7. Put the compact spare tire near you.
5-88