2010 CHEVROLET TAHOE coolant temperature

Consistency of Readings
Always check the fluid level at least twice using
the procedure described previously. Consistency
(repeatable readings) is important to maintaining proper
fluid level. If readings are still inconsistent, contact your
dealer.
Cooling System
If the vehicle is a Two-mode Hybrid, see the Two-mode
Hybrid manual for more information.
The cooling system allows the engine to maintain the
correct working temperature.
5.3L Engine shown, 6.0L and 6.2L Engine similar
A. Coolant Surge Tank
B. Coolant Surge Tank Pressure Cap
C. Engine Cooling Fan(s)
6-30

What to Use
{WARNING:
Adding only plain water to the cooling system can
be dangerous. Plain water, or some other liquid
such as alcohol, 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 7‑12for more information.
6-32

4. With the coolant surge tank pressure cap off, startthe engine and let it run until you can feel the
upper radiator hose getting hot. Watch out for the
engine cooling fan.
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. 5. Replace the pressure cap. Be sure the pressure
cap is hand-tight and fully seated.
6. Verify coolant level after engine is shut off and the coolant is cold. If necessary, repeat coolant fill
procedure Steps 1 through 6.
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.
Engine Overheating
The vehicle has several indicators to warn of engine
overheating.
There is a coolant temperature gauge on your vehicle's
instrument panel. See Engine Coolant Temperature
Gauge on page 4‑38.
In addition, ENGINE OVERHEATED STOP ENGINE,
ENGINE OVERHEATED IDLE ENGINE, and a ENGINE
POWER IS REDUCED message comes on in the Driver
Information Center (DIC) on the instrument panel. See
DIC Warnings and Messages on page 4‑61.
6-36

If No Steam Is Coming From The
Engine Compartment
The ENGINE OVERHEATED STOP ENGINE or the
ENGINE OVERHEATED IDLE ENGINE message, along
with a low coolant condition, can indicate a serious
problem.
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. SeeTowing a Trailer on page 5‑47. 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 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.
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”
later in this section.
6-38

Overheated Engine Protection
Operating Mode
If an overheated engine condition exists and the
ENGINE POWER IS REDUCED message 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 the 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 6‑17.
Engine Fan Noise
If the vehicle has a clutched engine cooling fan, when
the clutch is engaged, the fan spins faster to provide
more air to cool the engine. In most everyday driving
conditions, the fan is spinning slower and the clutch is
not fully engaged. This improves fuel economy and
reduces fan noise. Under heavy vehicle loading, trailer
towing, and/or high outside temperatures, the fan speed
increases as the clutch more fully engages, so you may
hear an increase in fan noise. This is normal and should
not be mistaken as the transmission slipping or making
extra shifts. It is merely the cooling system functioning
properly. The fan will slow down when additional cooling
is not required and the clutch disengages.
You may also hear this fan noise when you start the
engine. It will go away as the fan clutch partially
disengages.
If the vehicle has electric cooling fans, you may hear
the fans spinning at low speed during most everyday
driving. The fans may turn off if no cooling is required.
Under heavy vehicle loading, trailer towing, and/or high
outside temperatures, or if you are operating the air
conditioning system, the fans may change to high
speed and you may hear an increase in fan noise.
This is normal and indicates that the cooling system is
functioning properly. The fans will change to low speed
when additional cooling is no longer required.
6-39

Windshield Washer Fluid
What to Use
When windshield washer fluid needs to be added, be
sure to read the manufacturer's instructions before use.
Use a fluid that has sufficient protection against freezing
in an area where the temperature may fall below
freezing.
Adding Washer Fluid
The vehicle has a low washer fluid message in the
DIC that comes on when the washer fluid is low. The
message is displayed for 15 seconds at the start of
each ignition cycle. When the WASHER FLUID LOW
ADD FLUID message displays, you will need to add
washer fluid to the windshield washer fluid reservoir.
Open the cap with the
washer symbol on it.
Add washer fluid until the
tank is full. SeeEngine
Compartment Overview
on page 6‑16for
reservoir location. Notice:
.When using concentrated washer fluid,
follow the manufacturer's instructions for
adding water.
.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. Also, water does
not clean as well as washer fluid.
.Fill the washer fluid tank only three-quarters
full when it is very cold. This allows for fluid
expansion if freezing occurs, which could
damage the tank if it is completely full.
.Do not use engine coolant (antifreeze) in
the windshield washer. It can damage the
vehicle's windshield washer system and
paint.
6-41

When the Change Engine Oil Soon message displays,
certain services, checks, and inspections are required.
The services described for MaintenanceIshould be
performed at every engine oil change. The services
described for Maintenance IIshould be
performed when:
.Maintenance Iwas performed the last time the
engine oil was changed.
.It has been 10 months or more since the Change
Engine Oil Soon message has displayed or since
the last service.
Maintenance I
.Change engine oil and filter. See Engine Oilon
page 6‑17. An Emission Control Service.
.Engine coolant level check. See Engine Coolanton page 6‑31.
.Windshield washer fluid level check. See
Windshield Washer Fluid on page 6‑41.
.Tire inflation check. SeeInflation - Tire Pressureon page 6‑72.
.Tire wear inspection. See Tire Inspection and
Rotation on page 6‑78.
.Rotate tires. See Tire Inspection and Rotationon
page 6‑78.
.Fluids visual leak check (or every 12 months,
whichever occurs first). A leak in any system must
be repaired and the fluid level checked.
.Engine air cleaner filter inspection (vehicles driven
in dusty conditions only). See Engine Air Cleaner/
Filter on page 6‑21.
.Brake system inspection (or every 12 months,
whichever occurs first).
Maintenance II
.Perform all services described in Maintenance I.
.Steering and suspension inspection. Visual
inspection for damaged, loose, or missing parts or
signs of wear.
.Lubricate the front suspension, steering linkage,
and parking brake cable guides. Control arm ball
joints on 2500 series vehicles require lubrication
but should not be lubricated unless their
temperature is−12°C (10°F) or higher, or they
could be damaged. Control arm ball joints on
1500 series vehicles are maintenance‐free.
.Engine cooling system inspection. Visual
inspection of hoses, pipes, fittings, and clamps
and replacement, if needed.
7-4

Cleaning (cont.)Underbody Maintenance . . . . . . . . . . . . . . . . . . . . . . . . . 6-115
Washing Your Vehicle . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-111
Weatherstrips . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-111
Windshield, Backglass, and Wiper Blades . . . . . . . 6-113
Climate Control System . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-18 Outlet Adjustment . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-26
Rear Air Conditioning and Heating System . . . . . . . 4-26
Rear Air Conditioning and Heating System,Electronic . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-28
Climate Control Systems Dual Automatic . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-20
Climate Controls . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-18
Clock, Setting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-81
Collision Damage Repair . . . . . . . . . . . . . . . . . . . . . . . . . . 8-12
Compass . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-58
Content Theft-Deterrent . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-22
Control of a Vehicle . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .5-3
Coolant Engine . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-31
Engine Temperature Gauge . . . . . . . . . . . . . . . . . . . . . . 4-38
Cooled Seats . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2-9
Cooling System . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-30 Courtesy Transportation Program . . . . . . . . . . . . . . . . . . 8-10
Cruise Control . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .4-8
Light . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-44
Cupholders . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-73
Customer Assistance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .8-6 Offices . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8-6
Text Telephone (TTY) Users . . . . . . . . . . . . . . . . . . . . . . . 8-6
Customer Information Service Publications Ordering Information . . . . . . . . 8-16
Customer Satisfaction Procedure . . . . . . . . . . . . . . . . . . . .8-2
D
Damage Repair, Collision . . . . . . . . . . . . . . . . . . . . . . . . . . 8-12
Data Recorders, Event . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8-18
Daytime Running Lamps (DRL) . . . . . . . . . . . . . . . . . . . . 4-12
Defensive Driving . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .5-2
Delayed Locking . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-11
DIC Compass . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-58
Disc, MP3 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-99, 4-106
Doing Your Own Service Work . . . . . . . . . . . . . . . . . . . . . . .6-5
Dome Lamp Override . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-15
Dome Lamps . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-14
i - 4