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4. Check both sides of the dipstick and read the lowerlevel. The fluid level must be in the
cross-hatched area.
5. If the fluid level is in the acceptable range, push the dipstick back in all the way and turn the handle
clockwise.
6. Reinstall the engine air cleaner/filter assembly.
How to Add Automatic Transmission
Fluid
Refer to the Maintenance Schedule to determine what
kind of transmission fluid to use. See Recommended
Fluids and Lubricants on page 7‑9. If the fluid level is low, add only enough of the proper
fluid to bring the level into the cross-hatched area on
the dipstick.
1. Pull out the dipstick.
2. Using a long-neck funnel, add enough fluid at the dipstick hole to bring it to the proper level.
It does not take much fluid, generally less than
one pint (0.5 L). Do not overfill.
Notice: Use of the incorrect automatic transmission
fluid may damage the vehicle, and the damages may
not be covered by the vehicle's warranty. Always
use the automatic transmission fluid listed in
Recommended Fluids and Lubricants on page 7‑9.
3. After adding fluid, recheck the fluid level as described under “How to Check Automatic
Transmission Fluid,” earlier in this section.
4. When the correct fluid level is obtained, push the dipstick back in all the way and turn the handle
clockwise.
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Black plate (24,1)Cadillac DTS Owner Manual - 2011
Cooling System
The cooling system allows the engine to maintain the correct working temperature.
4.6L L37 Engine shown, 4.6L LD8 Engine similar
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A. Coolant Surge Tank with Pressure Cap
B. Electric Engine Cooling Fans
{WARNING:
An electric engine cooling fan under the hood 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:
Heater and radiator hoses, and other engine
parts, can be very hot. Do not touch them. If you
do, you can be burned.(Continued)
WARNING: (Continued)
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 fire, and you could be burned.
Get any leak fixed before you drive the vehicle.
Notice: Using coolant other than DEX-COOL
®can
cause premature engine, heater core, or radiator
corrosion. In addition, the engine coolant could
require changing sooner, at 50 000 km (30,000 miles)
or 24 months, whichever occurs first. Any repairs
would not be covered by the vehicle warranty.
Always use DEX-COOL (silicate-free) coolant in the
vehicle.
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Engine Coolant
The cooling system in the vehicle is filled with
DEX-COOL®engine coolant. This coolant is designed
to remain in the vehicle for five years or 150,000 miles
(240 000 km), whichever occurs first.
The following explains the cooling system and how to
check and add coolant when it is low. If there is a
problem with engine overheating, see Engine
Overheating on page 6‑29.
What to Use
{WARNING:
Adding only plain water or some other liquid to the
cooling system can be dangerous. Plain water
and other liquids, 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 fire and you or
others could be burned. Use a 50/50 mixture of
clean, drinkable water and DEX-COOL coolant. Use a 50/50 mixture of clean, drinkable water and
DEX-COOL
®coolant. If using this mixture, nothing else
needs to be added. This mixture:
.Gives freezing protection down to −34°F (−37°C),
outside temperature.
.Gives boiling protection up to 265°F (129°C),
engine temperature.
.Protects against rust and corrosion.
.Will not damage aluminum parts.
.Helps keep the proper engine temperature.
Notice: If an improper coolant mixture is used, the
engine could overheat and be badly damaged. The
repair cost would not be covered by the vehicle
warranty. Too much water in the mixture can freeze
and crack the engine, radiator, heater core, and
other parts.
Notice: If extra inhibitors and/or additives are used
in the vehicle's cooling system, the vehicle could be
damaged. Use only the proper mixture of the engine
coolant listed in this manual for the cooling system.
See Recommended Fluids and Lubricants
on
page 7‑9for more information.
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Checking Coolant
The vehicle must be on a level surface when checking
the coolant level.
Check to see if coolant is visible in the coolant recovery
tank. If the coolant inside the coolant recovery 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 FULL COLD mark, add a 50/50 mixture of
clean, drinkable water and DEX-COOL
®coolant at the
coolant recovery tank, but be sure the cooling system is
cool before this is done. See Engine Coolant
on
page 6‑26for more information.
How to Add Coolant to the Surge Tank
{WARNING:
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.
Notice: This vehicle has a specific coolant fill
procedure. Failure to follow this procedure could
cause the engine to overheat and be severely
damaged.
{WARNING:
An electric engine cooling fan under the hood 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.
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4.6L L37 Engine shown, 4.6L LD8 Engine similar
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. Replace the cap. Be sure the cap is hand‐tight and fully seated. 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.
If coolant is needed, add the proper DEX-COOL
®
coolant mixture at the coolant recovery tank.
Engine Overheating
The vehicle has several indicators to warn of engine
overheating.
There is an engine temperature warning light and/or
gauge on the instrument panel cluster. See Engine
Coolant Temperature Warning Light
on page 4‑53and
Engine Coolant Temperature Gauge on page 4‑53.
The vehicle may also display a ENGINE OVERHEATED
IDLE ENGINE message or an ENGINE OVERHEATED
STOP ENGINE message displayed in the Driver
Information Center (DIC). See DIC Warnings and
Messages
on page 4‑65for more information. You will
also hear a chime.
The decision may be made not to lift the hood when
this warning appears, but instead get service help right
away. See Roadside Service on page 8‑7.
If the decision is made to lift the hood , make sure the
vehicle is parked on a level surface.
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Then check to see if the engine cooling fans are
running. If the engine is overheating, both fans should
be running. If they are not, do not continue to run the
engine and have the vehicle serviced.
Notice:Engine damage from running the engine
without coolant is not covered by the warranty.
Notice: If the engine catches fire while driving with
no coolant, the vehicle can be badly damaged. The
costly repairs would not be covered by the vehicle
warranty. See Overheated Engine Protection
Operating Mode
on page 6‑31for information on
driving to a safe place in an emergency.
If Steam Is Coming From The Engine
Compartment
{WARNING:
Steam from an overheated engine can burn you
badly, even if you just open the hood. Stay away
from the engine if you see or hear steam coming
from it. Turn it off and get everyone away from
the vehicle until it cools down. Wait until there is
no sign of steam or coolant before you open
the hood.
(Continued)
WARNING: (Continued)
If you keep driving when the vehicles engine is
overheated, the liquids in it can catch fire. You or
others could be badly burned. Stop the engine if
it overheats, and get out of the vehicle until the
engine is cool.
SeeOverheated Engine Protection Operating
Mode
on page 6‑31for information on driving to
a safe place in an emergency.
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.
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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. In heavy traffic, let the engine idle in N (Neutral) while stopped. If it 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 vehicle in front. If the warning
does not come back on, continue to drive normally.
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
If an overheated engine condition exists and the
message ENGINE OVERHEATED STOP ENGINE
is displayed, an overheat protection mode which
alternates firing groups of cylinders helps prevent
engine damage. In this mode, you will notice a loss in
power and engine performance. This operating mode
allows your vehicle to be driven to a safe place in an
emergency. 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, change the oil
and reset the oil life system. See Engine Oil
on
page 6‑15.
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