2008 CADILLAC STS check engine

Maintenance Schedule
Introduction
Important: Keep engine oil at the proper level and
change as recommended.
Have you purchased the GM Protection Plan? The Plan
supplements your new vehicle warranties. See your
Warranty and Owner Assistance booklet or your
dealer/retailer for details.
Maintenance Requirements
Notice:Maintenance intervals, checks, inspections,
replacement parts, and recommended uids and
lubricants as prescribed in this manual are
necessary to keep your vehicle in good working
condition. Any damage caused by failure to follow
scheduled maintenance might not be covered
by warranty.
Your Vehicle and the Environment
Proper vehicle maintenance not only helps to keep your
vehicle in good working condition, but also helps the
environment. All recommended maintenance is
important. Improper vehicle maintenance can even
affect the quality of the air we breathe. Improper uid
levels or the wrong tire ination can increase the level
of emissions from your vehicle. To help protect our
environment, and to keep your vehicle in good condition,
be sure to maintain your vehicle properly.
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When you go to your dealer/retailer for your service
needs, you will know that trained and supported service
technicians will perform the work using genuine parts.
If you want to purchase service information, seeService
Publications Ordering Information on page 7-15.
Owner Checks and Services on page 6-9tells you what
should be checked, when to check it, and what you
can easily do to help keep your vehicle in good
condition.
The proper replacement parts, uids, and lubricants to
use are listed inRecommended Fluids and Lubricants
on page 6-13andNormal Maintenance Replacement
Parts on page 6-15. When your vehicle is serviced,
make sure these are used. All parts should be replaced
and all necessary repairs done before you or anyone
else drives the vehicle. We recommend the use of
genuine parts from your dealer/retailer.Scheduled Maintenance
To maintain the ride, handling, and performance of your
vehicle, it is important that the rst tire rotation service
be performed when the vehicle has 5,000 to 8,000 miles
(8 000 to 13 000 km). Check tires for ination pressures
and wear. SeeTires on page 5-57. If tire rotation is
recommended for your vehicle, rotate tires. SeeTire
Inspection and Rotation on page 5-73and “Tire Wear
Inspection” inAt Least Once a Month on page 6-10.
When the CHANGE ENGINE OIL SOON message in the
Driver Information Center (DIC) comes on, it means
that service is required for your vehicle. Have your
vehicle serviced as soon as possible within the next
600 miles (1 000 km). It is possible that, if you are
driving under the best conditions, the engine oil life
system may not indicate that vehicle service is
necessary for over a year. However, the engine oil and
lter must be changed at least once a year and at
this time the system must be reset. Your dealer/retailer
has trained service technicians who will perform this
work using genuine parts and reset the system.
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If the engine oil life system is ever reset accidentally,
you must service your vehicle within 3,000 miles
(5 000 km) since your last service. Remember to
reset the oil life system whenever the oil is changed.
SeeEngine Oil Life System on page 5-21for
information on the Engine Oil Life System and
resetting the system.
When the CHANGE ENGINE OIL SOON message
appears, the following services, checks, and inspections
are required:
❑Change engine oil and lter. SeeEngine Oil on
page 5-18. Reset oil life system. SeeEngine Oil Life
System on page 5-21.An Emission Control Service.
❑Visually check for any leaks or damage.
See footnote (k).
❑Inspect engine air cleaner lter. If necessary, replace
lter. SeeEngine Air Cleaner/Filter on page 5-23.
See footnote (m).❑Check tires for ination pressures and wear. SeeTires
on page 5-57. If tire rotation is recommended for your
vehicle, rotate tires. SeeTire Inspection and Rotation
on page 5-73and “Tire Wear Inspection” inAt Least
Once a Month on page 6-10.
❑Inspect brake system.See footnote (a).
❑Check engine coolant and windshield washer uid
levels. If you have the 4.4L V8 supercharged engine,
check intercooler uid level. Add uid as needed.
❑Perform any needed additional services.
See “Additional Required Services” in this section.
❑Inspect suspension and steering components.
See footnote (b).
❑Inspect engine cooling system.See footnote (c).
❑Inspect wiper blades.See footnote (d).
❑Inspect restraint system components.
See footnote (e).
❑Lubricate body components.See footnote (f).
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(i)If using DOT-4 brake fluid only: Drain, flush, and refill
brake hydraulic system at a regular maintenance
service every two years. This service can be complex;
you should have your dealer/retailer perform this service.
See Brakes on page 5-41.
(j)Drain, flush, and refill cooling system. This service
can be complex; you should have your dealer/retailer
perform this service. See Engine Coolant on page 5-25
for what to use. Inspect hoses. Clean radiator,
condenser, pressure cap, and filler neck. Pressure test
the cooling system and pressure cap.
(k)A fluid loss in any vehicle system could indicate a
problem. Have the system inspected and repaired
and the fluid level checked. Add fluid if needed.
(l)Drain, flush, and refill intercooler system. This service
can be complex; you should have your dealer/retailer
perform this service. See Engine Coolant on page 5-25.
(m)If you drive regularly under dusty conditions,
inspect the filter at each engine oil change.
(n)Visually inspect belt for fraying, excessive cracks, or
obvious damage. Replace belt if necessary.Owner Checks and Services
These owner checks and services should be performed
at the intervals specied to help ensure the safety,
dependability, and emission control performance of your
vehicle. Your dealer/retailer can assist you with these
checks and services.
Be sure any necessary repairs are completed at once.
Whenever any uids or lubricants are added to your
vehicle, make sure they are the proper ones, as shown
inRecommended Fluids and Lubricants on page 6-13.
At Each Fuel Fill
It is important to perform these underhood checks at
each fuel fill.
Engine Oil Level Check
Notice:It is important to check the engine oil
regularly and keep it at the proper level. Failure to
keep the engine oil at the proper level can cause
damage to the engine not covered by your warranty.
Check the engine oil level and add the proper oil if
necessary. SeeEngine Oil on page 5-18.
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Engine Coolant Level Check
Check the engine coolant level and add DEX-COOL®
coolant mixture if necessary. SeeEngine Coolant
on page 5-25.
Intercooler Coolant Level Check
(4.4L Supercharged Engine)
Check the coolant level and add DEX-COOL®coolant
mixture if necessary. SeeEngine Coolant on page 5-25.
Windshield Washer Fluid Level Check
Check the windshield washer uid level in the
windshield washer uid reservoir and add the proper
uid if necessary. SeeWindshield Washer Fluid
on page 5-40.
At Least Once a Month
Tire Ination Check
Inspect your vehicle’s tires and make sure they are
inated to the correct pressures. Do not forget to check
the spare tire. SeeInflation - Tire Pressure on
page 5-66. Check to make sure the spare tire is stored
securely. SeeChanging a Flat Tire on page 5-96.
Tire Wear Inspection
Tire rotation is recommended if your vehicle has the
same size tires at all four wheel positions and may be
required for high mileage highway drivers prior to
the Engine Oil Life System service notication.
Check the tires for wear and, if necessary, rotate the
tires. SeeTire Inspection and Rotation on page 5-73.
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At Least Once a Year
Starter Switch Check
{CAUTION:
When you are doing this inspection, the
vehicle could move suddenly. If the vehicle
moves, you or others could be injured.
1. Before you start, be sure you have enough room
around the vehicle.
2. Firmly apply both the parking brake and the regular
brake. SeeParking Brake on page 2-35.
Do not use the accelerator pedal, and be ready to
turn off the engine immediately if it starts.
3. Try to start the engine in each gear. The vehicle
should start only in PARK (P) or NEUTRAL (N).
If the vehicle starts in any other position, contact
your dealer/retailer for service.
Automatic Transmission Shift Lock
Control System Check
{CAUTION:
When you are doing this inspection, the
vehicle could move suddenly. If the vehicle
moves, you or others could be injured.
1. Before you start, be sure you have enough room
around the vehicle. It should be parked on a level
surface.
2. Firmly apply the parking brake. SeeParking Brake
on page 2-35.
Be ready to apply the regular brake immediately if
the vehicle begins to move.
3. With the engine off and without applying the regular
brake, try to move the shift lever out of PARK (P)
with normal effort. If the shift lever moves out
of PARK (P), contact your dealer/retailer for service.
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Parking Brake and Automatic
Transmission Park (P) Mechanism Check
{CAUTION:
When you are doing this check, your vehicle
could begin to move. You or others could be
injured and property could be damaged.
Make sure there is room in front of your
vehicle in case it begins to roll. Be ready to
apply the regular brake at once should the
vehicle begin to move.Park on a fairly steep hill, with the vehicle facing
downhill. Keeping your foot on the regular brake,
set the parking brake.
To check the parking brake’s holding ability:
With the engine running and transmission in
NEUTRAL (N), slowly remove foot pressure from
the regular brake pedal. Do this until the vehicle is
held by the parking brake only.
To check the PARK (P) mechanism’s holding
ability: With the engine running, shift to PARK (P).
Then release the parking brake followed by the
regular brake.
Contact your dealer/retailer if service is required.
Underbody Flushing Service
At least every spring, use plain water to ush any
corrosive materials from the underbody. Take care to
clean thoroughly any areas where mud and other debris
can collect.
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Service Publications Ordering
Information
Service Manuals
Service Manuals have the diagnosis and repair
information on engines, transmission, axle suspension,
brakes, electrical, steering, body, etc.
Service Bulletins
Service Bulletins’ give additional technical service
information needed to knowledgeably service General
Motors cars and trucks. Each bulletin contains
instructions to assist in the diagnosis and service of
your vehicle.
Owner Information
Owner publications are written specically for owners
and intended to provide basic operational information
about the vehicle. The owner manual includes the
Maintenance Schedule for all models.
In-Portfolio: Includes a Portfolio, Owner Manual, and
Warranty Booklet.
RETAIL SELL PRICE: $35.00 (U.S.) plus processing fee
Without Portfolio: Owner Manual only.
RETAIL SELL PRICE: $25.00 (U.S.) plus processing fee
Current and Past Model Order Forms
Technical Service Bulletins and Manuals are available
for current and past model GM vehicles. To request
an order form, specify year and model name of
the vehicle.
ORDER TOLL FREE: 1-800-551-4123
Monday-Friday 8:00 AM - 6:00 PM
Eastern Time
For Credit Card Orders Only
(VISA-MasterCard-Discover), visit Helm, Inc. on the
World Wide Web at: www.helminc.com
Or you can write to:
Helm, Incorporated
P.O. Box 07130
Detroit, MI 48207
Prices are subject to change without notice and without
incurring obligation. Allow ample time for delivery.
Note to Canadian Customers: All listed prices are
quoted in U.S. funds. Canadian residents are to make
checks payable in U.S. funds.
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