2005 CADILLAC CTS V service

Doing Your Own Service Work
If you want to do some of your own service work, you
will want to 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,
seeService Publications Ordering Information on
page 7-11.
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 6-15.{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.
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Notice:Your vehicle was not designed for fuel
that contains methanol. Do not use fuel containing
methanol. It can corrode metal parts in your fuel
system and also damage the plastic and rubber
parts. That damage would not be covered under
your warranty.
Some gasolines that are not reformulated for low
emissions may contain an octane-enhancing additive
called methylcyclopentadienyl manganese tricarbonyl
(MMT); ask the attendant where you buy gasoline
whether the fuel contains MMT. General Motors does
not recommend the use of such gasolines. Fuels
containing MMT can reduce the life of spark plugs and
the performance of the emission control system may
be affected. The malfunction indicator lamp may turn
on. If this occurs, return to your authorized GM dealer
for service.Fuels in Foreign Countries
If you plan on driving in another country outside the
United States or Canada, the proper fuel may be hard
to nd. Never use leaded gasoline or any other fuel
not recommended in the previous text on fuel. Costly
repairs caused by use of improper fuel would not
be covered by your warranty.
To check the fuel availability, ask an auto club, or
contact a major oil company that does business in
the country where you will be driving.
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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 your oil. The recommended
oils with the starburst symbol that meet GM Standard
GM4718M are all you will 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.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 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.
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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.
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 CTS Navigation System Owner
Supplement 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.
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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 6-14for 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 ame 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.
Automatic Transmission Fluid
It is not necessary to check the transmission uid level.
A transmission uid leak is the only reason for uid
loss. If a leak occurs, take your vehicle to your Cadillac
dealership service department and have it repaired
as soon as possible.
Change the uid and lter at the intervals listed in
Additional Required Services on page 6-6, and be sure
to use the transmission uid listed inRecommended
Fluids and Lubricants on page 6-12.
Notice:Use of the incorrect automatic transmission
uid may damage your vehicle, and the damages
may not be covered by your warranty. Always
use the automatic transmission uid listed in
Recommended Fluids and Lubricants on page 6-12.
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Manual Transmission Fluid
When to Check
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 Cadillac dealership service department and have
it repaired as soon as possible.
How to Check
Because this operation can be difficult, you may choose
to have this done at your Cadillac dealership 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
part 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.
How to Add Fluid
Here is how to add uid. SeeRecommended Fluids and
Lubricants on page 6-12to 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.
5-24

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 6-12.
How to Check and Add Fluid
Make sure the uid level is at the MIN 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.
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.
5-25

If you get the overheat warning with no sign of steam,
try this for a minute or so:
1. In heavy traffic, let the engine idle in NEUTRAL (N)
while stopped. If it is safe to do so, pull off the
road, shift to PARK (P) or NEUTRAL (N) and let
the engine idle.
2. Set the climate controls to the highest heat
setting and fan speed and open the windows,
as necessary.
If you no longer have the overheat warning, you can
drive. Just to be safe, drive slower for about 10 minutes.
If the warning does not come back on, you can drive
normally.
If the warning continues and you have not stopped, pull
over, stop, and park your vehicle right away.
If there is still no sign of steam, you can idle the engine
for three minutes while you are parked. If you still
have the warning,turn off the engine and get everyone
out of the vehicleuntil it cools down.
You may decide not to lift the hood but to get service
help right away.Overheated Engine Protection
Operating Mode
This operating mode allows your vehicle to be driven to
a safe place in an emergency. Should an overheated
engine condition exist, an overheat protection mode
which alternates ring groups of cylinders helps prevent
engine damage. In this mode, you will notice a loss
in power and engine performance. A low coolant and/or
engine overheat warning will indicate that an overheat
condition exists. Driving extended miles (km) and/or
towing a trailer in the overheat protection mode should
be avoided.
Notice:After driving in the overheated engine
protection operating mode, to avoid engine damage,
allow the engine to cool before attempting any
repair. The engine oil will be severely degraded.
Repair the cause of coolant loss and change the oil.
SeeEngine Oil on page 5-16.
5-30