2008 CADILLAC STS maintenance

ENGINE OIL LIFE
If your vehicle has this display, it shows the estimated
oil life remaining. If you see 99% ENGINE OIL LIFE
on the display, that means that 99% of the current oil
life remains.
When the oil life is depleted, the CHANGE ENGINE OIL
SOON message will appear on the display. Change
the oil as soon as possible. In addition to the engine oil
life system monitoring the oil life, additional maintenance
is recommended in the Maintenance Schedule in this
manual. SeeScheduled Maintenance on page 6-4
andEngine Oil on page 5-18.
After an oil change, reset the ENGINE OIL LIFE display.
To reset, seeEngine Oil Life System on page 5-21.
The display will show 100% ENGINE OIL LIFE after
it has been reset. Also clear the CHANGE ENGINE OIL
SOON message from the display.
ENGLISH DISPLAY UNITS
(METRIC DISPLAY UNITS)
This display allows you to select between English and
metric units of measurement if your vehicle has the
uplevel DIC. Press the reset button to switch between
English and metric units.
Blank Line
This display shows no information.
ENGINE BOOST (STS-V Only)
This display shows a graphic that indicates the amount
of boost the engine is receiving in either pounds per
square inch (psi) or kilopascals (kPa).
ENGINE OIL TEMPERATURE (STS-V Only)
This display shows the engine oil temperature in
either degrees Fahrenheit (°F) or degrees Celsius (°C).
OIL PRESSURE (STS-V Only)
This display shows the oil pressure in either pounds
per square inch (psi) or kilopascals (kPa).
TRANS (Transmission) FLUID TEMP
(Temperature) (STS-V Only)
This display shows the transmission uid temperature in
either degrees Fahrenheit (°F) or degrees Celsius (°C).
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CHANGE ENGINE OIL SOON
This message displays when the engine oil needs to be
changed. See your dealer/retailer. SeeEngine Oil on
page 5-18andScheduled Maintenance on page 6-4for
more information.
After resetting the CHANGE ENGINE OIL SOON
message by clearing it from the display, reset the engine
oil life system separately. For more information on
resetting the engine oil life system, seeEngine Oil Life
System on page 5-21.
CHECK BRAKE FLUID
This message displays if the ignition is on to inform the
driver that the brake uid level is low. Have the brake
system serviced by your dealer/retailer as soon as
possible. SeeBrake System Warning Light on page 3-64
for more information.
CHECK GAS CAP
This message displays when the fuel cap has not been
fully tightened. Recheck the fuel cap to ensure that it
is on and tightened properly.
CHECK TIRE PRESSURE
This message displays when the pressure in one or
more of the vehicle’s tires needs to be checked. If a tire
pressure message appears on the DIC, stop as soon
as you can. Have the tire pressures checked and set
to those shown on the Tire Loading Information
label. SeeTires on page 5-57,Loading Your Vehicle on
page 4-26, andInflation - Tire Pressure on page 5-66.
The DIC also shows the tire pressure values. See
DIC Operation and Displays on page 3-74. If the tire
pressure is low, the low tire pressure warning light
comes on. SeeTire Pressure Light on page 3-67.
CHECK WASHER FLUID
This symbol appears
with this message.
This message displays when the windshield washer
uid is low. Fill the windshield washer uid reservoir
as soon as possible. SeeWindshield Washer Fluid
on page 5-40for more information.
3-83

3. When the wheel chocks are in place, release the
regular brakes until the chocks absorb the load.
4. Reapply the regular brakes. Then apply your
parking brake, and then shift to PARK (P).
5. Release the regular brakes.
When You Are Ready to Leave After
Parking on a Hill
1. Apply your regular brakes and hold the pedal down
while you:
Start your 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
Your vehicle will need service more often when you’re
pulling a trailer. See the Maintenance Schedule for more
on this. Things that are especially important in trailer
operation are automatic transmission uid (don’t overll),
engine oil, drive belt, cooling system and brake
system. Each of these is covered in this manual, and
the Index will help you nd them quickly. If you’re
trailering, it’s a good idea to review this information
before you start your trip.
Check periodically to see that all hitch nuts and bolts
are tight.
Engine Cooling When Trailer Towing
Your cooling system may temporarily overheat during
severe operating conditions. SeeEngine Overheating on
page 5-29.
Towing a Trailer (Vehicles Without
Heavy Duty Cooling)
Vehicles without heavy duty cooling are neither designed
nor intended to tow a trailer.
4-40

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

California Perchlorate Materials
Requirements
Certain types of automotive applications, such as airbag
initiators, seat belt pretensioners, and lithium batteries
contained in remote keyless entry transmitters, may
contain perchlorate materials. Special handling may be
necessary. For additional information, see
www.dtsc.ca.gov/hazardouswaste/perchlorate.
Doing Your Own Service Work
{CAUTION:
You can be injured and your vehicle could be
damaged if you try to do service work on a
vehicle without knowing enough about it.
Be sure you have sufficient knowledge,
experience, the proper replacement parts,
and tools before you attempt any vehicle
maintenance task.
Be sure to use the proper nuts, bolts, and
other fasteners. English and metric
fasteners can be easily confused. If you
use the wrong fasteners, parts can later
break or fall off. You could be hurt.If you want to do some of your own service work, you
should use the proper service manual. It tells you much
more about how to service your vehicle than this
manual can. To order the proper service manual, see
Service Publications Ordering Information on page 7-15.
Your vehicle has an airbag system. Before attempting
to do your own service work, seeServicing Your
Airbag-Equipped Vehicle on page 1-64.
You should keep a record with all parts receipts and list
the mileage and the date of any service work you
perform. SeeMaintenance Record on page 6-18.
Adding Equipment to the Outside of
Your Vehicle
Things you might add to the outside of your vehicle can
affect the airow around it. This can cause wind
noise and can affect fuel economy and windshield
washer performance. Check with your dealer/retailer
before adding equipment to the outside of your vehicle.
5-4

Fuel
Use of the recommended fuel is an important part of the
proper maintenance of your vehicle. To help keep the
engine clean and maintain optimum vehicle
performance, we recommend the use of gasoline
advertised as TOP TIER Detergent Gasoline.
The 8th digit of the Vehicle Identication Number (VIN)
shows the code letter or number that identies your
vehicle’s engine. The VIN is at the top left of the
instrument panel. SeeVehicle Identification Number
(VIN) on page 5-116.
Gasoline Octane
If your vehicle has the 3.6L V6 engine (VIN Code V),
use regular unleaded gasoline with a posted octane
rating of 87 or higher. If the octane rating is less than 87,
you might notice an audible knocking noise when you
drive, commonly referred to as spark knock. If this
occurs, use a gasoline rated at 87 octane or higher as
soon as possible. If you are using gasoline rated at
87 octane or higher and you hear heavy knocking, the
engine needs service.If your vehicle has the 4.6L V8 engine (VIN Code A),
use premium unleaded gasoline with a posted octane
rating of 91 or higher. You can also use regular
unleaded gasoline rated at 87 octane or higher, but
your vehicle’s acceleration could be slightly reduced,
and you might notice a slight audible knocking
noise, commonly referred to as spark knock. If the
octane is less than 87, you might notice a heavy
knocking noise when you drive. If this occurs, use a
gasoline rated at 87 octane or higher as soon as
possible. Otherwise, you could damage the engine.
If you are using gasoline rated at 87 octane or higher
and you hear heavy knocking, the engine needs service.
If your vehicle has the 4.4L V8 engine (VIN Code D), use
premium unleaded gasoline with a posted octane rating
of 91 or higher. For best performance, use premium
unleaded gasoline with a posted octane rating of 93. In
an emergency, you can use regular unleaded gasoline
with an octane rating of 87 or higher. If 87 octane fuel is
used, do not perform any aggressive driving maneuvers
such as wide open throttle applications. You might also
hear audible spark knock during acceleration. Rell the
tank with premium fuel as soon as possible to avoid
damaging the engine. If you are using gasoline rated at
91 octane or higher and you hear heavy knocking, the
engine needs service.
5-5

Engine Air Cleaner/Filter
The engine air cleaner/lter is in the engine
compartment on the driver’s side of the vehicle, near
the front. SeeEngine Compartment Overview on
page 5-11for more information on locating the air
cleaner/lter.
When to Inspect the Engine
Air Cleaner/Filter
Inspect the air cleaner/lter at the MaintenanceII
intervals and replace it at the rst oil change after each
50,000 mile (80 000 km) interval. SeeScheduled
Maintenance on page 6-4for more information. If you
are driving in dusty/dirty conditions, inspect the lter
at each engine oil change.
How to Inspect the Engine
Air Cleaner/Filter
To inspect the air cleaner/lter remove the lter from
the vehicle and lightly shake the lter to release
loose dust and dirt. If the lter remains caked with dirt,
a new lter is required.
To inspect or replace the lter in the 3.6L V6 or
4.6L V8 engines, do the following:
1. Remove the two screws located on the top of
the cover.
2. Disconnect the coolant recovery hose so that it
is not going across the top of the engine air
cleaner/lter. 4.6L V8 Engine shown, 3.6L V6 Engine similar
5-23

3. Loosen the clamp and remove the duct from the
passenger’s side of the engine air cleaner/lter.
4. The two sides of the airbox are hinged at the
bottom. Open the airbox by pushing the top of
the airbox cover toward the engine.
5. Remove the air lter by lifting it straight up through
the opening in the airbox.
6. Inspect or replace the engine air cleaner/lter. See
Normal Maintenance Replacement Parts on
page 6-15for the correct part number for the lter.
7. Reinstall the cover by reversing Steps 1 through 4.
If your vehicle has the 4.4L V8 STS-V engine, there
is a special procedure for checking and changing the air
cleaner/lter. Because this procedure is difficult, you
should have this done at the dealership service
department. Contact your dealer for additional
information or the procedure can be found in the service
manual. To purchase a service manual, seeService
Publications Ordering Information on page 7-15.
{CAUTION:
Operating the engine with the air cleaner/lter
off can cause you or others to be burned.
The air cleaner not only cleans the air; it helps
to stop ames if the engine backres. If it is
not there and the engine backres, you could
be burned. Do not drive with it off, and be
careful working on the engine with the air
cleaner/lter off.
Notice:If the air cleaner/lter is off, a backre can
cause a damaging engine re. And, dirt can
easily get into your engine, which will damage it.
Always have the air cleaner/lter in place when you
are driving.
5-24