2007 CADILLAC DTS PROFESSIONAL engine coolant

Cooling System
When you decide it is safe to lift the hood, here is what you will see:
A. Coolant Surge Tank with Pressure Cap B. Electric Engine Cooling Fans
4.6L L37 Engine shown, 4.6L LD8 Engine similar
380

{CAUTION:
An electric engine cooling fan under the
hood can start up even when the engine
is not running and can injure you. Keep
hands, clothing, and tools away from any
underhood electric fan.
If the coolant inside the coolant surge tank is
boiling, do not do anything else until it cools down.
The vehicle should be parked on a level surface.
{CAUTION:
Heater and radiator hoses, and other
engine parts, can be very hot. Do not
touch them. If you do, you can be burned.
Do not run the engine if there is a leak. If
you run the engine, it could lose all
coolant. That could cause an engine re,
and you could be burned. Get any leak
xed before you drive the vehicle.If there seems to be no leak, with the engine on,
check to see if the electric engine cooling fans
are running. If the engine is overheating, both fans
should be running. If they are not, your vehicle
needs service.
Notice:Engine damage from running your
engine without coolant is not covered by your
warranty. SeeOverheated Engine Protection
Operating Mode on page 379for information on
driving to a safe place in an emergency.
Notice:Using coolant other than DEX-COOL
®
may cause premature engine, heater core, or
radiator corrosion. In addition, the engine
coolant could require changing sooner, at
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.
381

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 level is not at the FULL COLD
mark located on the side of the surge tank,
add enough of a 50/50 mixture of clean, drinkable
water and DEX-COOL
®coolant at the coolant
surge tank to bring the level to the FULL COLD
mark, but be sure the cooling system, including the
coolant surge tank pressure cap, is cool before
you do it. SeeEngine Coolant on page 374
for more information.If no coolant is visible in the surge tank, add
coolant as follows:
{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.
382

{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: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.
1. You can remove the
coolant surge tank
pressure cap when
the cooling system,
including the coolant
surge tank pressure
cap and upper
radiator hose, is no
longer hot.
Turn the pressure cap slowly counterclockwise.
If you hear a hiss, wait for that to stop. A hiss
means there is still some pressure left.
2. Then keep turning the cap and remove it.
383

3. Fill the coolant
surge tank with the
proper mixture
to the FULL COLD
mark on the
side of the coolant
surge tank.4. With the coolant surge tank 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 FULL COLD mark on the side of
the coolant surge tank.
5. Then replace the cap. Be sure the cap is
hand-tight and fully seated.
4.6L L37 Engine shown, 4.6L LD8 Engine similar
384

Windshield Washer Fluid
What to Use
When you need windshield washer uid, be sure
to read the manufacturer’s instructions before
use. If you will be operating your vehicle in an area
where the temperature may fall below freezing,
use a uid that has sufficient protection against
freezing.
Adding Washer Fluid
The WASHER FLUID LOW ADD FLUID message
will be displayed on the Driver Information
Center (DIC) when the uid is low. SeeDIC
Warnings and Messages on page 246for more
information.
Open the cap with the
washer symbol on it.
Add washer uid
until the tank is full. See
Engine Compartment
Overview on page 364
for reservoir location.Notice:
When using concentrated washer uid,
follow the manufacturer’s instructions
for adding water.
Do not mix water with ready-to-use washer
uid. Water can cause the solution to
freeze and damage your washer uid tank
and other parts of the washer system.
Also, water does not clean as well
as washer uid.
Fill the washer uid tank only
three-quarters full when it is very cold.
This allows for uid expansion if freezing
occurs, which could damage the tank if it is
completely full.
Do not use engine coolant (antifreeze) in
your windshield washer. It can damage
the vehicle’s windshield washer system
and paint.
386

Scheduled Maintenance
Service MaintenanceIMaintenanceII
Change engine oil and lter. SeeEngine Oil on page 365. Reset oil life system.
SeeEngine Oil Life System on page 368.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 370.See footnote (m).•
Rotate tires and check ination pressures and wear. SeeTire Inspection and
Rotation on page 418and “Tire Wear Inspection” inAt Least Once a Month on
page 472.••
Inspect brake system.See footnote (a).••
Check engine coolant and windshield washer uid levels and 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).•
Check transmission uid level and add uid as needed.•
Replace passenger compartment air lter.See footnote (g).•
467

(j)Drain, ush, and rell cooling system. This
service can be complex; you should have
your dealer/retailer perform this service. See
Engine Coolant on page 374 for what to use.
Inspect hoses. Clean radiator, condenser, pressure
cap, and ller neck. Pressure test the cooling
system and pressure cap.
(k)A uid loss in any vehicle system could
indicate a problem. Have the system inspected
and repaired and the uid level checked. Add uid
if needed.
(l)Visually inspect belt for fraying, excessive
cracks, or obvious damage. Replace belt if
necessary.
(m)If you drive regularly under dusty conditions,
inspect the lter at each engine oil change.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 GM
Goodwrench
®dealer 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 475.
471