2008 CADILLAC STS maintenance

The low tire pressure warning light may come on in cool
weather when the vehicle is rst started, and then
turn off as you start to drive. This could be an early
indicator that the air pressure in the tire(s) are getting
low and need to be inated to the proper pressure.
A Tire and Loading Information label, attached to your
vehicle, shows the size of your vehicle’s original
equipment tires and the correct ination pressure for your
vehicle’s tires when they are cold. SeeLoading Your
Vehicle on page 4-26for an example of the Tire and
Loading Information label and its location on your vehicle.
Also seeInflation - Tire Pressure on page 5-66.
Your vehicle’s TPMS can warn you about a low tire
pressure condition but it does not replace normal
tire maintenance. SeeTire Inspection and Rotation on
page 5-73andTires on page 5-57.
Your vehicle, when new, may have included a
factory-installed Tire Inator Kit. This kit uses a GM
approved liquid tire sealant. SeeTire Sealant and
Compressor Kit on page 5-87.
Notice:Using non-approved tire sealants could
damage the Tire Pressure Monitor System (TPMS)
sensors. TPMS sensor damage caused by using
an incorrect tire sealant is not covered by the
vehicle warranty. Always use the GM approved tire
sealant available through your dealer/retailer.TPMS Malfunction Light and Message
The TPMS will not function properly if one or more of the
TPMS sensors are missing or inoperable. When the
system detects a malfunction, the low tire warning light
ashes for about one minute and then stays on for
the remainder of the ignition cycle. A DIC warning
message is also displayed. The low tire warning light
and DIC warning message come on at each ignition
cycle until the problem is corrected. Some of the
conditions that can cause the malfunction light and
DIC message to come on are:
One of the road tires has been replaced with the
spare tire. The spare tire does not have a TPMS
sensor. The DIC message should go off once
you re-install the road tire containing the TPMS
sensor.
The TPMS sensor matching process was started
but not completed or not completed successfully
after rotating the vehicle’s tires. The DIC message
and TPMS malfunction light should go off once
the TPMS sensor matching process is performed
successfully. See “TPMS Sensor Matching Process”
later in this section.
5-71

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 the 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). SeeScheduled Maintenance on
page 6-4.
The purpose of a regular tire rotation is to achieve
a uniform wear for all tires on the vehicle. This
will ensure that the vehicle continues to perform
most like it did when the tires were new.
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 5-75
andWheel Replacement on page 5-80.When rotating P235/50R17 size tires or
255/45ZR18 size tires, always use the correct
rotation pattern shown here.
If the 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. SeeInflation - Tire
Pressure on page 5-66andLoading Your Vehicle
on page 4-26.
5-74

Reset the Tire Pressure Monitor System. SeeTire
Pressure Monitor Operation on page 5-70.
Make certain that all wheel nuts are properly
tightened. See “Wheel Nut Torque” under
Capacities and Specifications on page 5-128.
{CAUTION:
Rust or dirt on a wheel, or on the parts to
which it is fastened, can make wheel nuts
become loose after time. The wheel could
come off and cause an accident. When
you change a wheel, remove any rust or
dirt from places where the wheel attaches
to the vehicle. In an emergency, you can
use a cloth or a paper towel to do this;
but be sure to use a scraper or wire brush
later, if needed, to get all the rust or dirt
off. SeeChanging a Flat Tire on page 5-96.
When It Is Time for New Tires
Various factors, such as maintenance, temperatures,
driving speeds, vehicle loading, and road conditions
inuence when you need new tires.One way to tell when
it is time for new tires
is to check the treadwear
indicators, which will
appear when your
tires have only
1/16 inch (1.6 mm) or
less of tread remaining.
You need new tires if any of the following statements
are true:
You can see the indicators at three or more places
around the tire.
You can see cord or fabric showing through the
tire’s rubber.
The tread or sidewall is cracked, cut, or snagged
deep enough to show cord or fabric.
The tire has a bump, bulge, or split.
The tire has a puncture, cut, or other damage that
cannot be repaired well because of the size or
location of the damage.
5-75

The rubber in tires degrades over time, even if they are
not being used. This is also true for the spare tire, if
your vehicle has one. Multiple conditions affect how fast
this aging takes place, including temperatures, loading
conditions, and ination pressure maintenance. With
proper care and maintenance tires will typically wear out
before they degrade due to age. If you are unsure
about the need to replace your tires as they get older,
consult the tire manufacturer for more information.
Buying New Tires
GM has developed and matched specic tires for your
vehicle. The original equipment tires installed on
your vehicle, when it was new, were designed to meet
General Motors Tire Performance Criteria Specication
(TPC Spec) system rating. If you need replacement
tires, GM strongly recommends that you get tires with
the same TPC Spec rating. This way, your vehicle
will continue to have tires that are designed to give the
same performance and vehicle safety, during normal
use, as the original tires.
GM’s exclusive TPC Spec system considers over a
dozen critical specications that impact the overall
performance of your vehicle, including brake system
performance, ride and handling, traction control, and tire
pressure monitoring performance. GM’s TPC Spec
number is molded onto the tire’s sidewall near the tire
size. If the tires have an all-season tread design,the TPC Spec number will be followed by an MS for
mud and snow. SeeTire Sidewall Labeling on page 5-59
for additional information.
GM recommends replacing tires in sets of four. This is
because uniform tread depth on all tires will help keep
your vehicle performing most like it did when the tires
were new. Replacing less than a full set of tires can affect
the braking and handling performance of your vehicle.
The optional 18-inch performance tires, size
255/45ZR18 99Y, used on some vehicles, meets the
General Motors Tire Performance Criteria Specication
(TPC Spec) rating but the TPC Spec code has not
been molded onto the tire’s sidewall. If your vehicle has
these tires, and you need to replace them, you can
still get these TPC Spec rated tires by asking your
GM dealer. Your GM dealer can order these tires by part
number. This way, your vehicle will continue to give
the proper endurance, handling, traction, and ride as the
original 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 snow tires with
a lower speed rating, never exceed the tire’s maximum
speed capability.
5-76

If a Tire Goes Flat
It is unusual for a tire to blowout while you are driving,
especially if you maintain your tires properly. See
Tires on page 5-57. If air goes out of a tire, It is much
more likely to leak out slowly. But if you should ever
have a blowout, here are a few tips about what to expect
and what to do:
If a front tire fails, the at tire will create a drag that
pulls the vehicle toward that side. Take your foot off the
accelerator pedal and grip the steering wheel rmly.
Steer to maintain lane position, and then gently brake to
a stop well out of the traffic lane.
A rear blowout, particularly on a curve, acts much like a
skid and may require the same correction you would
use in a skid. In any rear blowout, remove your foot from
the accelerator pedal. Get the vehicle under control
by steering the way you want the vehicle to go. It may
be very bumpy and noisy, but you can still steer. Gently
brake to a stop, well off the road if possible.
If a tire goes at, and your vehicle has a compact spare
tire, seeChanging a Flat Tire on page 5-96. 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.
If your vehicle has 255/45ZR18 size tires, there is no
spare tire, jack, or tire changing equipment. A tire inator
kit, included with your vehicle, may be used to seal
small punctures in the tread area of the tire. SeeTire
Sealant and Compressor Kit on page 5-87.
5-86

4. Attach the wheel wrench to the jack.
{CAUTION:
Getting under a vehicle when it is jacked up is
dangerous. If the vehicle slips off the jack, you
could be badly injured or killed. Never get under
a vehicle when it is supported only by a jack.
{CAUTION:
Raising your vehicle with the jack improperly
positioned can damage the vehicle and even
make the vehicle fall. To help avoid personal
injury and vehicle damage, be sure to t the
jack lift head into the proper location before
raising the vehicle.
{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.
5-100

Finish Damage
Any stone chips, fractures or deep scratches in the
nish should be repaired right away. Bare metal
will corrode quickly and may develop into major repair
expense.
Minor chips and scratches can be repaired with touch-up
materials available from your dealer/retailer. Larger
areas of nish damage can be corrected in your
dealer’s/retailer’s body and paint shop.
Underbody Maintenance
Chemicals used for ice and snow removal and dust
control can collect on the underbody. If these are not
removed, corrosion and rust can develop on the
underbody parts such as fuel lines, frame, oor pan,
and exhaust system even though they have corrosion
protection.
At least every spring, ush these materials from the
underbody with plain water. Clean any areas where mud
and debris can collect. Dirt packed in close areas of
the frame should be loosened before being ushed.
Your dealer/retailer or an underbody car washing system
can do this for you.
Chemical Paint Spotting
Some weather and atmospheric conditions can create a
chemical fallout. Airborne pollutants can fall upon and
attack painted surfaces on the vehicle. This damage can
take two forms: blotchy, ring-shaped discolorations,
and small, irregular dark spots etched into the
paint surface.
Although no defect in the paint job causes this, we will
repair, at no charge to the owner, the surfaces of
new vehicles damaged by this fallout condition within
12 months or 12,000 miles (20 000 km) of purchase,
whichever occurs rst.
5-114

Maintenance Schedule......................................6-2
Introduction...................................................6-2
Maintenance Requirements..............................6-2
Your Vehicle and the Environment....................6-2
Using the Maintenance Schedule......................6-3
Scheduled Maintenance...................................6-4
Additional Required Services............................6-6
Maintenance Footnotes...................................6-8Owner Checks and Services............................6-9
At Each Fuel Fill............................................6-9
At Least Once a Month.................................6-10
At Least Once a Year...................................6-11
Recommended Fluids and Lubricants...............6-13
Normal Maintenance Replacement Parts..........6-15
Engine Drive Belt Routing..............................6-16
Maintenance Record.....................................6-18
Section 6 Maintenance Schedule
6-1