2006 CADILLAC CTS engine

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.
When the system has calculated that oil life has been
diminished, it will indicate that an oil change is necessary.
A change engine oil message in the Driver Information
Center (DIC) will come on. Change your 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 may not indicate that an oil change
is necessary for over a year. However, your engine oil
and lter must be changed at least once a year and
at this time the system must be reset. Your dealer has
GM-trained service people who will perform this work
using genuine GM parts and reset the system. It is also
important to check your oil regularly and keep it at the
proper level.
If the system is ever reset accidentally, you must
change your 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.
How to Reset the Engine Oil Life
System and the Oil Life Indicator
The Engine Oil Life System calculates when to change
your engine oil and lter based on vehicle use. Anytime
your oil is changed, reset the system so it can calculate
when the next oil change is required. If a situation occurs
where you change your oil prior to a change engine oil
message in the DIC being turned on, reset the system.
After the oil has been changed, the change engine
oil message and the oil life indicator must be reset.
To reset the message and indicator, use one of
the following procedures:
Base Audio System
Press the CLR button located to the right of the DIC
display to acknowledge the change engine oil message.
This will clear the message from the display and reset it.
To reset the oil life indicator, use the following steps:
1. Press the up or down arrow on the INFO button
located to the right of the DIC display to access
the DIC menu.
2. Once XXX% ENGINE OIL LIFE menu item is
highlighted, press and hold the CLR button.
The percentage will return to 100, and the oil life
indicator will be reset. Repeat the steps if the
percentage does not return to 100.
3. Turn the key to OFF.
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If the change engine oil message comes back on when
you start your vehicle, the engine oil life system has
not reset. Repeat the procedure.
Navigation System
If you have the navigation system, see “Vehicle
Customization” in the Navigation System Manual for
how to reset the oil life indicator.
What to Do with Used Oil
Used engine oil contains certain elements that may be
unhealthy for your skin and could even cause cancer.
Do not let used oil stay on your skin for very long. Clean
your skin and nails with soap and water, or a good
hand cleaner. Wash or properly dispose of clothing or
rags containing used engine oil. See the manufacturer’s
warnings about the use and disposal of oil products.
Used oil can be a threat to the environment. If you
change your own oil, be sure to drain all the oil from the
lter before disposal. Never dispose of oil by putting it in
the trash, pouring it on the ground, into sewers, or into
streams or bodies of water. Instead, recycle it by taking
it to a place that collects used oil. If you have a problem
properly disposing of your used oil, ask your dealer,
a service station or a local recycling center for help.
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 5-12for more information on location.CTS shown, CTS-V similar
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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 (83 000 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 engine air cleaner/lter,
do the following:
1. Remove the two screws located on the sides of
the cover.
2. Lift the cover off.3. Inspect or replace the engine air cleaner/lter.
SeeNormal Maintenance Replacement Parts
on page 6-15for the correct part number for
the lter.
4. Reinstall the cover by reversing Steps 1 and 2.
{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.
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Manual Transmission Fluid
When to Check Manual
Transmission Fluid
It is not necessary to check the manual transmission
uid level. A transmission uid leak is the only reason
for uid loss. If a leak occurs, take the vehicle to
your GM dealer service department and have it
repaired as soon as possible.
How to Check Manual
Transmission Fluid
Because this operation can be difficult, you may choose
to have this done at your GM dealer service department.
If you do it yourself, be sure to follow all the instructions
here, or you could get a false reading.
Notice:Too much or too little uid can damage
your transmission. Too much can mean that some
of the uid could come out and fall on hot engine
parts or exhaust system parts, starting a re.
Too little uid could cause the transmission to
overheat. Be sure to get an accurate reading
if you check your transmission uid.Check the uid level only when your engine is off, the
vehicle is parked on a level place and the transmission
is cool enough for you to rest your ngers on the
transmission case.
To check the uid level, do the following:
1. Remove the ller plug.
2. Check that the lubricant level is up to the bottom of
the ller plug hole.
3. If the uid level is good and your vehicle is a CTS,
replace the gasket and reinstall the ller plug. If the
uid level is good and your vehicle is a CTS-V,
apply LOCTITE
®#516 or equivalent sealant to the
threads and then reinstall the ller plug.
With either vehicle, be sure the plug is fully seated.
If the uid level is low, add more uid as described
in the next steps.
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How to Add Manual Transmission Fluid
Here is how to add uid. SeeRecommended Fluids
and Lubricants on page 6-13to determine which type of
uid to use.
1. Remove the ller plug.
2. Add uid at the ller plug hole. Add only enough
uid to bring the uid level up to the bottom of the
ller plug hole.
3. If your vehicle is a CTS, replace the gasket and
reinstall the ller plug. If your vehicle is a CTS-V,
apply LOCTITE
®#516 or equivalent sealant to
the threads and then reinstall the ller plug.
Again, with either vehicle, be sure the plug is
fully seated.
Hydraulic Clutch
It is not necessary to regularly check clutch uid
unless you suspect there is a leak in the system.
Adding uid will not correct a leak.
A uid loss in this system could indicate a problem.
Have the system inspected and repaired.
When to Check and What to Use
The hydraulic clutch uid
reservoir cap has this
symbol on it. SeeEngine
Compartment Overview
on page 5-12for reservoir
location.
Refer to the Maintenance Schedule to determine how
often you should check the uid level in your clutch
master cylinder reservoir and for the proper uid to use.
SeeOwner Checks and Services on page 6-9and
Recommended Fluids and Lubricants on page 6-13.
How to Check and Add Fluid
Make sure the uid level is at the MIN (Minimum)
line on the side of the reservoir. If it is not, remove
the cap and add the proper uid until the level reaches
the MIN line.
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Engine Coolant
The cooling system in your vehicle is lled with
DEX-COOL®engine coolant. This coolant is designed
to remain in your vehicle for ve years or 150,000 miles
(240 000 km), whichever occurs rst, if you add only
DEX-COOL
®extended life coolant.
The following explains your cooling system and
how to add coolant when it is low. If you have a problem
with engine overheating, seeEngine Overheating
on page 5-28.
A 50/50 mixture of clean, drinkable water and
DEX-COOL
®coolant will:
Give freezing protection down to−34°F (−37°C).
Give boiling protection up to 265°F (129°C).
Protect against rust and corrosion.
Help keep the proper engine temperature.
Let the warning lights and gages work as they should.
Notice:Using coolant other than DEX-COOL
®may
cause premature engine, heater core, or radiator
corrosion. In addition, the engine coolant may
require changing sooner, at the rst maintenance
service after each 30,000 miles (50 000 km) or
24 months, whichever occurs rst. Any repairs
would not be covered by your warranty. Always use
DEX-COOL
®(silicate-free) coolant in your vehicle.
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.
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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.
Checking Coolant
The coolant surge tank and pressure cap are located
on the driver’s side of the vehicle, toward the rear of the
engine compartment. SeeEngine Compartment
Overview on page 5-12for more information on location.
{CAUTION:
Turning the surge tank pressure cap when the
engine and radiator are hot can allow steam
and scalding liquids to blow out and burn
you badly. Never turn the surge tank pressure
cap — even a little — when the engine and
radiator are hot.
The vehicle must be on a level surface. When your
engine is cold, the coolant level should be at the
FULL COLD/FROID line on the side of the surge tank.
Follow the arrow from the top of the tank down the
side to the horizontal mark.
If the Check Coolant Level message in the Driver
Information Center (DIC) comes on and stays on,
it means you are low on engine coolant. SeeDIC
Warnings and Messages on page 3-61for more
information.
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Adding Coolant
If you need more coolant, add the proper DEX-COOL®
coolant mixture at the surge tank, but only when the
engine is cool.
{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.
When replacing the pressure cap, make sure it is
hand-tight and fully seated.
Coolant Surge Tank Pressure Cap
Notice:If the pressure cap is not tightly installed,
coolant loss and possible engine damage may
occur. Be sure the cap is properly and tightly
secured.
The coolant surge tank pressure cap must be fully
installed on the coolant surge tank. SeeEngine
Compartment Overview on page 5-12for more
information on location.
Engine Overheating
There are three engine hot messages that may be
displayed in the Driver Information Center (DIC).
SeeDIC Warnings and Messages on page 3-61for
more information.
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