2018 CADILLAC ATS engine coolant

Cadillac XTS Owner Manual (GMNA-Localizing-U.S./Canada-12032610) -
2019 - crc - 8/22/18
VEHICLE CARE 243
1.Engine Air Cleaner/Filter 0248.
2. Power Steering Fluid Reservoir (Under Engine Cover).
See Power Steering Fluid (LF3 and
LFX with AWD) 0255 orPower
Steering Fluid (LFX with FWD)
0 255.
3. Engine Oil Fill Cap. See Engine Oil
0 244.
4. Engine Oil Dipstick. See Engine
Oil 0244.
5. Engine Cover 0243.
6. Engine Cooling Fans (Out of View). See Cooling System 0250.
7. Charged Air Coolant Bottle and Pressure Cap. See Cooling System
0 250.
8. Brake Fluid Reservoir. See Brake
Fluid 0257. 9. Engine Coolant Surge Tank and
Pressure Cap. See Cooling System
0 250.
10. Battery - North America 0258
(Battery Cover not Shown).
11. Remote Positive (+) Terminal (Battery Cover not Shown). See
Jump Starting - North America
0306.
12. Engine Compartment Fuse Block
0265.
13. Windshield Washer Fluid Reservoir. See Washer Fluid
0 256.
14. Remote Negative (−) Terminal (Out of View). See Jump Starting -
North America 0306.Engine Cover
3.6L V6 Engine
1. Engine Oil Fill Cap
2. Engine Cover Bolt
3. Engine Cover
To remove:
1. Remove the oil fill cap (1).
2. Remove the engine cover bolt (2).
3. Raise the engine cover (3) to release it from the retainers.
4. Lift and remove the engine cover.
5. Reverse Steps 1–4 to reinstall the engine cover.

Cadillac XTS Owner Manual (GMNA-Localizing-U.S./Canada-12032610) -
2019 - crc - 8/22/18
250 VEHICLE CARE
Cooling System
The cooling system allows the engine
to maintain the correct working
temperature.
3.6L V6 Engine
1. Electric Engine Cooling Fans(Out of View)
2. Coolant Surge Tank and Pressure Cap
3.6L V6 Twin Turbo Engine
1. Electric Engine Cooling Fans(Out of View)
2. Charged Air Coolant (CAC) Bottle and Pressure Cap
3. Coolant Surge Tank and Pressure Cap
{Warning
An underhood electric fan can start
up even when the engine is not
running and can cause injury. Keep
hands, clothing, and tools away
from any underhood electric fan.
{Warning
Do not touch heater or radiator
hoses, or other engine parts. They
can be very hot and can burn you.
Do not run the engine if there is a
leak; all coolant could leak out.
That could cause an engine fire and
can burn you. Fix any leak before
driving the vehicle.
Engine Coolant
The engine and Charged Air Coolant
(CAC) cooling systems in the vehicle
are filled with DEX-COOL engine
coolant mixture.
See Recommended Fluids and
Lubricants 0332 and Maintenance
Schedule 0322.
The following explains the cooling
systems and how to check and add
coolant when it is low. If there is a
problem with engine overheating, see
Engine Overheating 0253.

Cadillac XTS Owner Manual (GMNA-Localizing-U.S./Canada-12032610) -
2019 - crc - 8/22/18
VEHICLE CARE 251
What to Use
{Warning
Plain water, or other liquids such as
alcohol, can boil before the proper
coolant mixture will. With plain
water or the wrong mixture, the
engine could get too hot but there
would not be an overheat warning.
The engine could catch fire and you
or others could be burned.
Use a 50/50 mixture of clean,
drinkable water and DEX-COOL
coolant. This mixture:
. Gives freezing protection down to
−37 °C (−34 °F), outside
temperature.
. Gives boiling protection up to
129 °C (265 °F), engine
temperature.
. Protects against rust and
corrosion.
. Will not damage aluminum parts.
. Helps keep the proper engine
temperature.
Caution
Do not use anything other than a
mix of DEX-COOL coolant that
meets GM Standard GMW3420 and
clean, drinkable water. Anything
else can cause damage to the
engine cooling system and the
vehicle, which would not be covered
by the vehicle warranty.
Never dispose of engine coolant by
putting it in the trash, pouring it on
the ground, or pouring into sewers,
streams, or bodies of water. Have the
coolant changed by an authorized
service center, familiar with legal
requirements regarding used coolant
disposal. This will help protect the
environment and your health.
Checking Coolant
The vehicle must be on a level surface
when checking the coolant level. The engine coolant surge tank and
CAC bottle are in the engine
compartment on the driver side of the
vehicle. See
Engine Compartment
Overview 0240.
Check to see if coolant is visible in the
surge tank and CAC bottle. If the
coolant inside the surge tank is
boiling, do not do anything else until
it cools down. If coolant is visible but
the coolant level is not at or above the
mark pointed to on the surge tank or
at the CAC bottle cold fill mark, add a
50/50 mixture of clean, drinkable
water and DEX-COOL coolant.
Be sure the cooling system is cool
before this is done.
If no coolant is visible in the coolant
surge tank or CAC bottle, add coolant
as follows:

Cadillac XTS Owner Manual (GMNA-Localizing-U.S./Canada-12032610) -
2019 - crc - 8/22/18
252 VEHICLE CARE
How to Add Coolant to the
Surge Tank
{Warning
Plain water, or other liquids such as
alcohol, can boil before the proper
coolant mixture will. With plain
water or the wrong mixture, the
engine could get too hot but there
would not be an overheat warning.
The engine could catch fire and you
or others could be burned.
{Warning
Spilling coolant on hot engine parts
can burn you. Coolant contains
ethylene glycol and it will burn if
the engine parts are hot enough.
Caution
Failure to follow the specific
coolant fill procedure could cause
the engine to overheat and could
cause system damage. If coolant is
not visible in the surge tank,
contact your dealer.
The coolant surge tank pressure cap
can be removed when the cooling
system, including the surge tank
pressure cap and upper radiator hose,
is no longer hot.
1. Turn the pressure cap slowly counterclockwise. If a hiss is
heard, wait for that to stop.
A hiss means there is still some
pressure left.
2. Keep turning the pressure cap slowly and remove it. 3. Fill the coolant surge tank with
the proper mixture to the mark
pointed to on the front of the
coolant surge tank.
4. With the coolant surge tank pressure cap off, start the engine,
and let it run until you can feel
the upper radiator hose getting
hot. Watch out for the engine
cooling fans. By this time, the
coolant level inside the coolant
surge tank may be lower. If the
level is lower, add more of the
proper mixture to the coolant
surge tank until the level reaches
the mark pointed to on the front
of the coolant surge tank.
5. Replace the pressure cap tightly.
6. Verify coolant level after the engine is shut off and the
coolant is cold. If necessary,
repeat coolant fill procedure
Steps 1–5.

Cadillac XTS Owner Manual (GMNA-Localizing-U.S./Canada-12032610) -
2019 - crc - 8/22/18
VEHICLE CARE 253
Caution
If the pressure cap is not tightly
installed, coolant loss and engine
damage may occur. Be sure the cap
is properly and tightly secured.
How to Add Coolant to the CAC
Bottle
{Warning
Spilling coolant on hot engine parts
can burn you. Coolant contains
ethylene glycol and it will burn if
the engine parts are hot enough.
Caution
Failure to follow the specific
coolant fill procedure could cause
the engine to overheat and could
cause system damage. If coolant is
not visible in the surge tank,
contact your dealer.The CAC bottle pressure cap can be
removed when the Charged Air
Coolant cooling system, including the
CAC bottle pressure cap, is no
longer hot.
1. Turn the pressure cap slowly
counterclockwise and remove it.
2. Fill the CAC bottle with the proper mixture to the cold fill
mark pointed to on the front of
the CAC bottle.
3. Replace the pressure cap tightly.
Caution
If the pressure cap is not tightly
installed, coolant loss and engine
damage may occur. Be sure the cap
is properly and tightly secured.
Engine Overheating
The vehicle has an engine coolant
temperature gauge and an engine
temperature light to warn of engine
overheating.
There are also engine hot messages
that may display in the Driver
Information Center (DIC).
If the decision is made not to lift the
hood when one of these warnings
appears, but get service help right
away. See Roadside Service 0343.
If the decision is made to lift the
hood, make sure the vehicle is parked
on a level surface.
Then check to see if the engine
cooling fans are running. If the engine
is overheating, the fans should be
running. If they are not, do not
continue to run the engine. Have the
vehicle serviced.

Cadillac XTS Owner Manual (GMNA-Localizing-U.S./Canada-12032610) -
2019 - crc - 8/22/18
254 VEHICLE CARE
Caution
Do not run the engine if there is a
leak in the engine cooling system.
This can cause a loss of all coolant
and can damage the system and
vehicle. Have any leaks fixed
right away.
If Steam Is Coming from the
Engine Compartment
{Warning
Steam and scalding liquids from a
hot cooling system are under
pressure. Turning the pressure cap,
even a little, can cause them to
come out at high speed and you
could be burned. Never turn the cap
when the cooling system, including
the pressure cap, is hot. Wait for
the cooling system and pressure
cap to cool.
If No Steam Is Coming from the
Engine Compartment
If an engine overheat warning is
displayed but no steam can be seen or
heard, the problem may not be too
serious. Sometimes the engine can get
a little too hot when the vehicle:
.Climbs a long hill on a hot day.
. Stops after high-speed driving.
. Idles for long periods in traffic.
. Tows a trailer.
If the overheat warning is displayed
with no sign of steam: 1. Turn the air conditioning off.
2. Turn the heater on to the highest temperature and to the highest
fan speed. Open the windows as
necessary.
3. When it is safe to do so, pull off the road, shift to P (Park) or
N (Neutral), and let the
engine idle.
If the temperature overheat gauge is
no longer in the overheat zone or an
overheat warning no longer displays,
the vehicle can be driven. Continue to drive the vehicle slow for about
10 minutes. Keep a safe vehicle
distance from the car in front of you.
If the warning does not come back on,
continue to drive normally and have
the cooling system checked for proper
fill and function.
If the warning continues, pull over,
stop, and park the vehicle right away.
If there is no sign of steam, idle the
engine for three minutes while parked.
If the warning is still displayed, turn
off the engine until it cools down.
Also, see
“Overheated Engine
Protection Operating Mode ”next in
this section.
Overheated Engine
Protection Operating Mode
This emergency operating mode
allows the vehicle to be driven to a
safe place in an emergency situation.
If an overheated engine condition
exists, an overheat protection mode,
which alternates firing groups of
cylinders, helps prevent engine

Cadillac XTS Owner Manual (GMNA-Localizing-U.S./Canada-12032610) -
2019 - crc - 8/22/18
VEHICLE CARE 255
damage. In this mode, there is
significant loss in power and engine
performance.
The engine coolant temperature
warning light comes on in the
instrument cluster, to indicate the
vehicle has entered overheated engine
protection operating mode. The
temperature gauge also indicates an
overheat condition exists. Driving
extended distances and/or towing a
trailer in the overheat protection
mode should be avoided.
Power Steering Fluid
(LF3 and LFX with AWD)
The power steering fluid reservoir is
under the engine cover on the
passenger side toward the rear of the
engine compartment. SeeEngine
Compartment Overview 0240.
When to Check Power Steering
Fluid
It is not necessary to regularly check
power steering fluid unless you
suspect there is a leak in the system
or an unusual noise is heard. A fluid
loss in this system could indicate a
problem. Have the system inspected
and repaired.
How to Check Power Steering
Fluid
Check the level when the engine
is cool.
To check the power steering fluid:
1. Remove the engine cover. Refer toEngine Cover 0243.
2. Wipe the cap and the top of the reservoir clean.
3. Turn the cap counterclockwise and pull it straight up.
4. Wipe the dipstick with a clean rag.
5. Replace the cap and completely tighten it. 6. Remove the cap again and look
at the fluid level on the dipstick.
The fluid level should be
between MIN and MAX on the
dipstick.
What to Use
To determine what kind of fluid to
use, see Recommended Fluids and
Lubricants 0332. Always use the
proper fluid.
Power Steering Fluid (LFX
with FWD)
The vehicle has electric power steering
and does not use power steering fluid.

Cadillac XTS Owner Manual (GMNA-Localizing-U.S./Canada-12032610) -
2019 - crc - 8/22/18
256 VEHICLE CARE
Washer Fluid
What to Use
When windshield washer fluid is
needed, be sure to read the
manufacturer's instructions before
use. If operating the vehicle in an area
where the temperature may fall below
freezing, use a fluid that has sufficient
protection against freezing.
Adding Washer Fluid
The appropriate message will appear
in the Driver Information Center (DIC)
when the fluid level is low.
Open the cap with the washer symbol
on it. Add washer fluid until the tank
is full. SeeEngine Compartment
Overview 0240 for reservoir location.
Caution
.
Do not use washer fluid that
contains any type of water
repellent coating. This can
cause the wiper blades to
chatter or skip.
. Do not use engine coolant
(antifreeze) in the windshield
washer. It can damage the
windshield washer system
and paint.
. Do not mix water with
ready-to-use washer fluid.
Water can cause the solution
to freeze and damage the
washer fluid tank and other
parts of the washer system.
. When using concentrated
washer fluid, follow the
manufacturer instructions for
adding water.
. Fill the washer fluid tank only
three-quarters full when it is
very cold. This allows for
fluid expansion if freezing
(Continued)
Caution (Continued)
occurs, which could damage
the tank if it is
completely full.
Brakes
Disc brake pads have built-in wear
indicators that make a high-pitched
warning sound when the brake pads
are worn and new pads are needed.
The sound can come and go or can be
heard all the time when the vehicle is
moving, except when applying the
brake pedal firmly.
{Warning
The brake wear warning sound
means that soon the brakes will not
work well. That could lead to a
crash. When the brake wear
warning sound is heard, have the
vehicle serviced.