2012 CHEVROLET SUBURBAN engine overheat

Black plate (25,1)Chevrolet Tahoe/Suburban Owner Manual - 2012
Driving and Operating 9-25
Notice:Cranking the engine for
long periods of time, by returning
the key to the START position
immediately after cranking has
ended, can overheat and damage
the cranking motor, and drain the
battery. Wait at least 15 seconds
between each try, to let the
cranking motor cool down.
2. If the engine does not start
after 5‐10 seconds, especially in
very cold weather (below −18°C
or 0°F), it could be flooded with
too much gasoline. Try pushing
the accelerator pedal all the way
to the floor and holding it there
as you hold the key in START
for up to a maximum of
15 seconds. Wait at least
15 seconds between each try, to
allow the cranking motor to cool
down. When the engine starts,
let go of the key and accelerator. If the vehicle starts briefly but
then stops again, repeat these
steps. This clears the extra
gasoline from the engine. Do not
race the engine immediately
after starting it. Operate the
engine and transmission gently
until the oil warms up and
lubricates all moving parts.
Notice: The engine is designed to
work with the electronics in the
vehicle. If you add electrical
parts or accessories, you could
change the way the engine
operates. Before adding electrical
equipment, check with your
dealer. If you do not, the engine
might not perform properly. Any
resulting damage would not be
covered by the vehicle warranty.Engine Heater
The engine coolant heater can
provide easier starting and better
fuel economy during engine
warm-up in cold weather conditions
at or below −18°C (0°F). Vehicles
with an engine heater should be
plugged in at least four hours before
starting. An internal thermostat in
the plug-end of the cord may exist
which will prevent engine coolant
heater operation at temperatures
above −18°C (0°F).
To Use the Engine Coolant
Heater
1. Turn off the engine.
2. Open the hood and unwrap
the electrical cord. The cord
is secured to the Engine
Compartment Fuse Block with
a clip. Carefully remove the
wire tie which secures the
electrical cord. Do not cut the
electrical cord.

Black plate (26,1)Chevrolet Tahoe/Suburban Owner Manual - 2012
9-26 Driving and Operating
3. Plug the cord into a normal,grounded 110-volt AC outlet.
{WARNING
Plugging the cord into an
ungrounded outlet could cause an
electrical shock. Also, the wrong
kind of extension cord could
overheat and cause a fire. You
could be seriously injured. Plug
the cord into a properly grounded
three-prong 110-volt AC outlet.
If the cord will not reach, use a
heavy-duty three-prong extension
cord rated for at least 15 amps.
4. Before starting the engine, be sure to unplug and store the
cord as it was before to keep
it away from moving engine
parts. If you do not, it could be
damaged. The length of time the heater should
remain plugged in depends on
several factors. Ask a dealer in the
area where you will be parking the
vehicle for the best advice on this.
Retained Accessory
Power (RAP)
The following vehicle accessories
can be used for up to 10 minutes
after the engine is turned off:
.Audio System
.Power Windows
.OnStar System (if equipped)
.Sunroof (if equipped)
These features work when the
key is in ON/RUN or ACC/
ACCESSORY. Once the key is
turned from ON/RUN to LOCK/OFF,
the windows and sunroof continue
to work up to 10 minutes until any
door is opened. The radio continues
to work for up to 10 minutes or until
the driver door is opened.
Shifting Into Park
{WARNING
It can be dangerous to get out of
the vehicle if the shift lever is not
fully in P (Park) with the parking
brake firmly set. The vehicle can
roll. If you have left the engine
running, the vehicle can move
suddenly. You or others could be
injured. To be sure the vehicle will
not move, even when you are
on fairly level ground, use the
steps that follow. If you have a
four-wheel drive transfer case
with a N (Neutral) position, and
the transfer case is in N (Neutral),
the vehicle will be free to roll,
even if the shift lever is in
P (Park). So, be sure the transfer
case is in a drive gear —not in
N (Neutral). If you are pulling a
(Continued)

Black plate (27,1)Chevrolet Tahoe/Suburban Owner Manual - 2012
Driving and Operating 9-27
WARNING (Continued)
trailer, seeDriving Characteristics
and Towing Tips on page 9‑66.
Always set the parking brake.
1. Hold the brake pedal down, then set the parking brake.
See Parking Brake on page 9‑44
for more information.
2. Move the shift lever into the P (Park) position by pulling the
shift lever toward you and
moving it up as far as it will go.
3. Be sure the transfer case is in a drive gear —not in N (Neutral).
4. Turn the ignition key to LOCK/OFF.
5. Remove the key and take it with you. If you can leave the vehicle
with the ignition key in your
hand, the vehicle is in P (Park).
Leaving the Vehicle With the
Engine Running
{WARNING
It can be dangerous to leave the
vehicle with the engine running.
The vehicle could move suddenly
if the shift lever is not fully in
P (Park) with the parking brake
firmly set.
If you have four-wheel drive and
the transfer case is in N (Neutral),
the vehicle will be free to roll,
even if the shift lever is in
P (Park). So be sure the transfer
case is in a drive gear —not in
N (Neutral).
And, if you leave the vehicle
with the engine running, it could
overheat and even catch fire. You
or others could be injured. Do not
leave the vehicle with the engine
running unless you have to. If you have to leave the vehicle with
the engine running, be sure your
vehicle is in P (Park) and the
parking brake is firmly set before
you leave it. After you move the shift
lever into P (Park), hold the regular
brake pedal down. Then, see if you
can move the shift lever away from
P (Park) without first pulling it toward
you. If you can, it means that the
shift lever was not fully locked into
P (Park).
Torque Lock
If you are parking on a hill and
you do not shift your transmission
into P (Park) properly, the weight
of the vehicle may put too much
force on the parking pawl in the
transmission. You may find it difficult
to pull the shift lever out of P (Park).
This is called torque lock. To
prevent torque lock, set the parking
brake and then shift into P (Park)
properly before you leave the driver
seat. To find out how, see
Shifting
Into Park on page 9‑26.

Black plate (68,1)Chevrolet Tahoe/Suburban Owner Manual - 2012
9-68 Driving and Operating
Backing Up
Hold the bottom of the steering
wheel with one hand. Then, to
move the trailer to the left, move
that hand to the left. To move the
trailer to the right, move your hand
to the right. Always back up slowly
and, if possible, have someone
guide you.
Making Turns
Notice:Making very sharp turns
while trailering could cause the
trailer to come in contact with the
vehicle. The vehicle could be
damaged. Avoid making very
sharp turns while trailering.
When turning with a trailer, make
wider turns than normal. Do this
so the trailer will not strike soft
shoulders, curbs, road signs, trees
or other objects. Avoid jerky or
sudden maneuvers. Signal well in
advance.
If the trailer turn signal bulbs burn
out, the arrows on the instrument
panel will still flash for turns. It is important to check occasionally to
be sure the trailer bulbs are still
working.
Driving on Grades
Reduce speed and shift to a
lower gear
beforestarting down a
long or steep downgrade. If the
transmission is not shifted down, the
brakes might get hot and no longer
work well.
Vehicles can tow in D (Drive). Shift
the transmission to a lower gear if
the transmission shifts too often
under heavy loads and/or hilly
conditions.
The tow/haul mode may be used if
the transmission shifts too often.
See Tow/Haul Mode Light on
page 5‑22.
When towing at high altitude on
steep uphill grades, consider the
following: Engine coolant will boil at
a lower temperature than at normal
altitudes. If the engine is turned off
immediately after towing at high
altitude on steep uphill grades, the vehicle may show signs similar to
engine overheating. To avoid this,
let the engine run while parked,
preferably on level ground, with the
automatic transmission in P (Park)
for a few minutes before turning the
engine off. If the overheat warning
comes on, see
Engine Overheating
on page 10‑19.
Parking on Hills
{WARNING
Parking the vehicle on a hill
with the trailer attached can be
dangerous. If something goes
wrong, the rig could start to move.
People can be injured, and both
the vehicle and the trailer can be
damaged. When possible, always
park the rig on a flat surface.

Black plate (1,1)Chevrolet Tahoe/Suburban Owner Manual - 2012
Vehicle Care 10-1
Vehicle Care
General Information
General Information . . . . . . . . . . 10-2
California Proposition65 Warning . . . . . . . . . . . . . . . . . 10-3
California Perchlorate Materials Requirements . . . . 10-3
Accessories and Modifications . . . . . . . . . . . . . . . 10-3
Vehicle Checks
Doing Your OwnService Work . . . . . . . . . . . . . . . 10-4
Hood . . . . . . . . . . . . . . . . . . . . . . . . 10-5
Engine Compartment Overview . . . . . . . . . . . . . . . . . . . 10-6
Engine Oil . . . . . . . . . . . . . . . . . . . 10-7
Engine Oil Life System . . . . . . 10-9
Automatic Transmission Fluid . . . . . . . . . . . . . . . . . . . . . . 10-11
Engine Air Cleaner/Filter . . . . 10-14
Cooling System . . . . . . . . . . . . 10-15
Engine Coolant . . . . . . . . . . . . . 10-16
Engine Overheating . . . . . . . . 10-19 Overheated Engine
Protection
Operating Mode . . . . . . . . . . . 10-21
Engine Fan . . . . . . . . . . . . . . . . . 10-21
Power Steering Fluid . . . . . . . 10-22
Washer Fluid . . . . . . . . . . . . . . . 10-23
Brakes . . . . . . . . . . . . . . . . . . . . . 10-24
Brake Fluid . . . . . . . . . . . . . . . . . 10-25
Battery . . . . . . . . . . . . . . . . . . . . . 10-26
Four-Wheel Drive . . . . . . . . . . . 10-27
Front Axle . . . . . . . . . . . . . . . . . . 10-27
Rear Axle . . . . . . . . . . . . . . . . . . 10-28
Starter Switch Check . . . . . . . 10-29
Automatic Transmission Shift Lock Control Function
Check . . . . . . . . . . . . . . . . . . . . . 10-30
Ignition Transmission Lock Check . . . . . . . . . . . . . . . . . . . . . 10-30
Park Brake and P (Park) Mechanism Check . . . . . . . . 10-30
Wiper Blade Replacement . . . . . . . . . . . . . . 10-31
Glass Replacement . . . . . . . . 10-32
Headlamp Aiming
Headlamp Aiming . . . . . . . . . . 10-32
Bulb Replacement
Bulb Replacement . . . . . . . . . . 10-34
Halogen Bulbs . . . . . . . . . . . . . . 10-34
Taillamps, Turn Signal, Stoplamps, and Back-Up
Lamps . . . . . . . . . . . . . . . . . . . . 10-34
License Plate Lamp . . . . . . . . 10-35
Replacement Bulbs . . . . . . . . . 10-36
Electrical System
Electrical System Overload . . . . . . . . . . . . . . . . . . 10-36
Fuses and Circuit Breakers . . . . . . . . . . . . . . . . . . 10-37
Engine Compartment Fuse Block . . . . . . . . . . . . . . . . . . . . . 10-37
Instrument Panel Fuse Block . . . . . . . . . . . . . . . . . . . . . 10-41
Wheels and Tires
Tires . . . . . . . . . . . . . . . . . . . . . . . . 10-44
Tire Sidewall Labeling . . . . . . 10-45
Tire Designations . . . . . . . . . . . 10-47
Tire Terminology and
Definitions . . . . . . . . . . . . . . . . 10-49
Tire Pressure . . . . . . . . . . . . . . . 10-52
Tire Pressure Monitor System . . . . . . . . . . . . . . . . . . . 10-53

Black plate (11,1)Chevrolet Tahoe/Suburban Owner Manual - 2012
Vehicle Care 10-11
If the vehicle has a CHANGE
ENGINE OIL SOON message
and it comes back on when the
vehicle is started and/or the OIL
LIFE REMAINING is near 0%, the
engine oil life system has not been
reset. Repeat the procedure.
Automatic Transmission
Fluid
When to Check and Change
Automatic Transmission Fluid
It is usually not necessary to check
the transmission fluid level. The
only reason for fluid loss is a
transmission leak or overheated
transmission. If a small leak is
suspected, then use the following
checking procedures to check the
fluid level. However, if there is a
large leak, then it may be necessary
to have the vehicle towed to a
dealer and have it repaired before
driving the vehicle further.Notice:
Use of the incorrect
automatic transmission fluid may
damage the vehicle, and the
damages may not be covered by
the vehicle warranty. Always use
the automatic transmission fluid
listed in Recommended Fluids
and Lubricants on page 11‑12.
Change the fluid and filter at the
scheduled maintenance intervals
listed in Maintenance Schedule on
page 11‑3. Be sure to use the
transmission fluid listed in
Recommended Fluids and
Lubricants on page 11‑12.
How to Check Automatic
Transmission Fluid
Notice: Too much or too
little fluid can damage the
transmission. Too much can
mean that some of the fluid could
come out and fall on hot engine
parts or exhaust system parts,
starting a fire. Too little fluid
could cause the transmission to overheat. Be sure to get an
accurate reading if checking
the transmission fluid.
Before checking the fluid level,
prepare the vehicle as follows:
1. Start the engine and park the
vehicle on a level surface. Keep
the engine running.
2. Apply the parking brake and place the shift lever in P (Park).
3. With your foot on the brake pedal, move the shift lever
through each gear range,
pausing for about three seconds
in each range. Then, move the
shift lever back to P (Park).
4. Allow the engine to idle (500 –800 rpm) for at least
1 minute. Slowly release the
brake pedal.
5. Keep the engine running and press the Trip/Fuel button or
trip odometer reset stem until
TRANS TEMP (Transmission
Temperature) displays on the
Driver Information Center (DIC).

Black plate (16,1)Chevrolet Tahoe/Suburban Owner Manual - 2012
10-16 Vehicle Care
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 5 years or
240 000 km (150,000 mi), 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,
seeEngine Overheating on
page 10‑19.
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 coolant warning system is set
for the proper coolant mixture.
With plain water or the wrong
(Continued)
WARNING (Continued)
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 −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.
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 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 11‑12 for
more information.
Never dispose of engine coolant by
putting it in the trash, pouring it on
the ground, or into sewers, streams,
or bodies of water. Have the coolant
changed by an authorized service

Black plate (17,1)Chevrolet Tahoe/Suburban Owner Manual - 2012
Vehicle Care 10-17
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.
Check to see if coolant is visible in
the coolant surge tank. If the coolant
inside the coolant 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 FULL COLD mark, add a
50/50 mixture of clean, drinkable
water and DEX-COOL coolant at the
coolant surge tank, but be sure the
cooling system is cool before this
is done.
The coolant surge tank is located in
the engine compartment on the
passenger side of the vehicle. See
Engine Compartment Overview on
page 10‑6for more information on
location.
The coolant level should be at or
above the FULL COLD mark. If it is
not, the vehicle may have a leak in
the cooling system.
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.