2008 CADILLAC STS adding oil

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

After you have removed the sight shields (if equipped) on the 3.6L V6 engine, here is what you will see:
A. Underhood Fuse Block. SeeUnderhood Fuse Block
on page 5-118.
B. Remote Negative (-) Terminal. SeeJump Starting on
page 5-45.
C. Remote Positive (+) Terminal. SeeJump Starting on
page 5-45.
D. Battery. SeeBattery on page 5-44.
E. Passenger Compartment Air Filter. SeePassenger
Compartment Air Filter on page 3-55.
F. Power Steering Fluid Reservoir. SeePower Steering
Fluid on page 5-39.
G. Engine Oil Fill Cap. See “When to Add Engine Oil”
underEngine Oil on page 5-18.H. Engine Oil Dipstick (Out of View). See “Checking
Engine Oil” underEngine Oil on page 5-18.
I. Brake Master Cylinder Reservoir. See “Brake Fluid”
underBrakes on page 5-41.
J. Engine Coolant Surge Tank and Pressure Cap. See
Coolant Surge Tank Pressure Cap on page 5-29
andCooling System on page 5-32.
K. Engine Air Cleaner/Filter. SeeEngine Air
Cleaner/Filter on page 5-23.
L. Windshield Washer Fluid Reservoir. See “Adding
Washer Fluid” underWindshield Washer Fluid
on page 5-40.
5-13

After you have removed the sight shields (if equipped) on the 4.6L V8 engine, here is what you will see:
A. Remote Negative (-) Terminal. SeeJump Starting on
page 5-45.
B. Remote Positive (+) Terminal. SeeJump Starting on
page 5-45.
C. Battery. SeeBattery on page 5-44.
D. Passenger Compartment Air Filter. SeePassenger
Compartment Air Filter on page 3-55.
E. Power Steering Fluid Reservoir. SeePower Steering
Fluid on page 5-39.
F. Engine Oil Fill Cap. See “When to Add Engine Oil”
underEngine Oil on page 5-18.
G. Engine Oil Dipstick (Out of View). See “Checking
Engine Oil” underEngine Oil on page 5-18.H. Brake Master Cylinder Reservoir. See “Brake Fluid”
underBrakes on page 5-41.
I. Engine Coolant Surge Tank and Pressure Cap. See
Coolant Surge Tank Pressure Cap on page 5-29
andCooling System on page 5-32.
J. Engine Air Cleaner/Filter. SeeEngine Air
Cleaner/Filter on page 5-23.
K. Underhood Fuse Block. SeeUnderhood Fuse Block
on page 5-118.
L. Windshield Washer Fluid Reservoir. See “Adding
Washer Fluid” underWindshield Washer Fluid
on page 5-40.
5-15

After you have removed the sight shields (if equipped) on the 4.4L V8 STS-V engine, here is what you will see:
A. Underhood Fuse Block. SeeUnderhood Fuse Block
on page 5-118.
B. Remote Positive (+) Terminal. SeeJump Starting on
page 5-45.
C. Remote Negative (-) Terminal. SeeJump Starting on
page 5-45.
D. Battery. SeeBattery on page 5-44.
E. Passenger Compartment Air Filter. SeePassenger
Compartment Air Filter on page 3-55.
F. Windshield Washer Fluid Reservoir. See “Adding
Washer Fluid” underWindshield Washer Fluid
on page 5-40.
G. Intercooler System Pressure Cap. SeeEngine
Coolant on page 5-25.
H. Power Steering Fluid Reservoir. SeePower Steering
Fluid on page 5-39.
I. Engine Oil Fill Cap. See “When to Add Engine Oil”
underEngine Oil on page 5-18.J. Engine Oil Dipstick (Out of View). See “Checking
Engine Oil” underEngine Oil on page 5-18.
K. Brake Master Cylinder Reservoir. See “Brake Fluid”
underBrakes on page 5-41.
L. Engine Coolant Surge Tank and Pressure Cap. See
Coolant Surge Tank Pressure Cap on page 5-29
andCooling System on page 5-32.
M. Engine Air Cleaner/Filter. SeeEngine Air
Cleaner/Filter on page 5-23.
If your vehicle is equipped with front compartment
underhood sight shields, before closing the hood be sure
to reinstall the sight shields. To reinstall the shields,
locate the tabs on the left and right sides and insert
them into the openings in the tower to tower brace. Then
insert the fasteners into the top of the shield and push
the fasteners back into place.
5-17

Your vehicle’s engine is lled at the factory with a
Mobil 1®synthetic oil, which meets all requirements for
your vehicle.
Substitute Engine Oil: When adding oil to maintain
engine oil level, oil meeting GM Standard GM4718M
may not be available. You can add substitute oil
designated SAE 5W-30 with the starburst symbol at all
temperatures. Substitute oil not meeting GM Standard
GM4718M should not be used for an oil change.
Engine Oil Additives
Do not add anything to the oil. The recommended oils
with the starburst symbol that meet GM standards are all
you need for good performance and engine protection.
Engine Oil Life System
When to Change Engine Oil
Your vehicle has a computer system that lets you know
when to change the engine oil and lter. This is based on
engine revolutions and engine temperature, and not on
mileage. Based on driving conditions, the mileage at
which an oil change will be indicated can vary
considerably. For the oil life system to work properly, you
must reset the system every time the oil is changed.Notice:If your vehicle is an STS-V model, the
engine uses a special oil lter. The use of any other
engine oil lter could lead to lter failure and
result in severe engine damage. Damage caused by
use of the wrong engine oil lter would not be
covered by your new vehicle warranty.
When the system has calculated that oil life has been
diminished, it will indicate that an oil change is
necessary. A CHANGE ENGINE OIL SOON message in
the DIC will come on. SeeDIC Warnings and Messages
on page 3-80. Change the oil 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 oil
life system might not indicate that an oil change
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 people who will perform this
work using genuine parts and reset the system. It is
also important to check the oil regularly and keep it at
the proper level.
If the system is ever reset accidentally, you must
change the oil at 3,000 miles (5 000 km) since your last
oil change. Remember to reset the oil life system
whenever the oil is changed.
5-21

What to Use
Use a mixture of one-half clean, drinkable water and
one-half DEX-COOL®coolant which will not damage
aluminum parts. If you use this coolant mixture, you do
not need to add anything else.
{CAUTION:
Adding only plain water to your cooling
system can be dangerous. Plain water, or
some other liquid such as alcohol, can boil
before the proper coolant mixture will. Your
vehicle’s coolant warning system is set for the
proper coolant mixture. With plain water or the
wrong mixture, your engine could get too hot
but you would not get the overheat warning.
Your engine could catch re and you or others
could be burned. Use a 50/50 mixture of clean,
drinkable water and DEX-COOL
®coolant.Notice:If you use an improper coolant mixture, your
engine could overheat and be badly damaged. The
repair cost would not be covered by your warranty.
Too much water in the mixture can freeze and crack
the engine, radiator, heater core, and other parts.
If you have to add coolant more than once or twice a
year, have your dealer check your cooling system.
Notice:If you use extra inhibitors and/or additives
in your vehicle’s cooling system, you could
damage your vehicle. Use only the proper mixture
of the engine coolant listed in this manual for
the cooling system. SeeRecommended Fluids and
Lubricants on page 6-13for more information.
5-26

How to Add Coolant to the Coolant
Surge Tank
If you have not found a problem yet, check to see if
coolant is visible in the surge tank. If coolant is visible
but the coolant level is not at the FULL COLD/FROID
line on the side of the coolant surge tank, add a
50/50 mixture of clean, drinkable water and DEX-COOL
®
coolant at the coolant surge tank, but be sure the
cooling system, including the coolant surge tank
pressure cap, is cool before you do it. SeeEngine
Coolant on page 5-25for more information.
{CAUTION:
Steam and scalding liquids from a hot cooling
system can blow out and burn you badly. They
are under pressure, and if you turn the coolant
surge tank pressure cap — even a little — they
can come out at high speed. Never turn the
cap when the cooling system, including the
coolant surge tank pressure cap, is hot. Wait
for the cooling system and coolant surge tank
pressure cap to cool if you ever have to turn
the pressure cap.
{CAUTION:
Adding only plain water to the cooling system
can be dangerous. Plain water, or some other
liquid such as alcohol, can boil before the
proper coolant mixture will. The vehicle’s
coolant warning system is set for the proper
coolant mixture. With plain water or the wrong
mixture, the engine could get too hot but you
would not get the overheat warning. The
engine could catch re and you or others
could be burned. Use a 50/50 mixture of clean,
drinkable water and DEX-COOL
®coolant.
Notice:In cold weather, water can freeze and crack
the engine, radiator, heater core and other parts.
Use the recommended coolant and the proper
coolant mixture.
5-34

{CAUTION:
Turning the Intercooler System pressure cap
when the engine and intercooler are hot can
allow steam and scalding liquids to blow out
and burn you badly. Never turn the Intercooler
System pressure cap, even a little, when the
engine and intercooler are hot.
{CAUTION:
Adding only plain water to the cooling system
can be dangerous. Plain water, or some other
liquid such as alcohol, can boil before the
proper coolant mixture will. The vehicle’s
coolant warning system is set for the proper
coolant mixture. With plain water or the wrong
mixture, the engine could get too hot but you
would not get the overheat warning. The
engine could catch re and you or others
could be burned. Use a 50/50 mixture of clean,
drinkable water and DEX-COOL
®coolant.Notice:In cold weather, water can freeze and crack
the engine, radiator, heater core and other parts.
Use the recommended coolant and the proper
coolant mixture.
{CAUTION:
You can be burned if you spill coolant on hot
engine parts. Coolant contains ethylene glycol
and it will burn if the engine parts are hot
enough. Do not spill coolant on a hot engine.
5-37