engine overheat HUMMER H3 2010 User Guide

Vehicle Care 10-13
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.
Wait at least 30 minutes before
checking the transmission fluid level
if you have been driving:
.When outside temperatures are
above 32°C (90°F).
.At high speed for quite a while.
.In heavy traffic —especially in
hot weather.
.While pulling a trailer.
To get the right reading, the fluid
should be at normal operating
temperature, which is 82°C to 93°C
(180°F to 200°F). Get the vehicle warmed up by
driving about 24 km (15 miles) when
outside temperatures are above
10°C (50°F). If it is colder than 10°C
(50°F), drive the vehicle in 3 (Third)
until the engine temperature gauge
moves and then remains steady for
10 minutes.
A cold fluid check can be made
after the vehicle has been sitting
for eight hours or more with the
engine off, but this is used only
as a reference. Let the engine run
at idle for five minutes if outside
temperatures are 10°C (50°F) or
more. If it is colder than 10°C
(50°F), the engine might have to
idle longer. Should the fluid level be
low during this cold check, check
the fluid hot before adding fluid.
Checking the fluid hot gives a more
accurate reading of the fluid level.
Checking the Fluid Level
To prepare the vehicle:
1. Park the vehicle on a level
place. Keep the engine running.
2. With the parking brake applied, 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, position the
shift lever in P (Park).
4. Let the engine run at idle for three minutes or more.

Vehicle Care 10-15
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 11‑8.
.After adding fluid, recheck the
fluid level as described under
“How to Check Automatic
Transmission Fluid,” earlier in
this section.
.When the correct fluid level is
obtained, push the dipstick back
in all the way; then flip the
handle down to lock the dipstick
in place.
Manual Transmission
Fluid
When to Check
A good time to check the manual
transmission fluid is when the
engine oil is changed. However, the
fluid in the manual transmission
does not require changing.
How to Check
Because this operation can be a
little difficult, you may choose to
have this done at your HUMMER
dealer service department.
If doing it yourself, be sure to follow
all the instructions here, or there
could be a false reading.
Notice: Too much or too
little fluid can damage the
transmission. Too little fluid
could cause the transmission
to overheat. Be sure to get an
accurate reading if checking the
transmission fluid. To check the fluid:
1. Park the vehicle on a level
surface, then shut the engine
off. Let the vehicle sit until the
transmission case is cool
enough to touch.
2. Remove the filler plug.
3. Check that the lubricant level isup to the bottom of the filler
plug hole.

Vehicle Care 10-19
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 240 000 km (150,000 miles),
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 10‑22.
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.
(Continued)
WARNING (Continued)
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 −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'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 11‑8for more
information.

10-20 Vehicle Care
Checking Coolant
The vehicle must be on a level
surface when checking the coolant
level.
The coolant recovery tank cap has
this symbol on it.
It is located toward the rear of
the engine compartment on the
passenger side of the vehicle. See
Engine Compartment Overview
on
page 10‑6for more information on
location.
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.
The vehicle must be on a level
surface. When the engine is cold,
the coolant level should be at FULL
COLD, or a little higher. When the
engine is warm, the level could be
above the FULL COLD level.
When the engine is cold, the coolant
level should be at least up to the
FULL COLD mark. If it is not, there
could be a leak in the cooling
system.
How to Add Coolant to the
Recovery 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.
When the coolant in the coolant
recovery tank is at the FULL COLD
mark, start the vehicle.
If coolant is needed, add the proper
DEX-COOL coolant mixture at the
coolant recovery tank.
How to Add Coolant to the
Radiator
{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.

10-22 Vehicle Care
6. Start the engine and let it rununtil you can feel the upper
radiator hose getting hot. Watch
out for the engine cooling fan.
7. By this time, the coolant level inside the radiator filler neck
might be lower. If the level is
lower, add more of the proper
DEX‐COOL coolant mixture
through the filler neck until the
level reaches the base of the
filler neck.
8. Then replace the pressure cap. At any time during this procedure
if coolant begins to flow out of
the filler neck, reinstall the
pressure cap.
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 an indicator to warn
of engine overheating.
A coolant temperature gauge is
displayed on the instrument panel.
See Engine Coolant Temperature
Gauge on page 5‑9.
You may decide not to lift the
hood when this warning appears,
but instead get service help right
away. See Roadside Service
on
page 13‑5.
If you do decide 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, both fans
should be running. If they are not,
do not continue to run the engine
and have the vehicle serviced.
The air conditioning might stop
working if the engine is too hot. This
is normal and helps cool the engine.
Notice:
Engine damage from
running the engine without
coolant is not covered by the
warranty.
Notice: If the engine catches
fire because of being driven
with no coolant, your vehicle can
be badly damaged. The costly
repairs would not be covered by
the vehicle warranty.

Vehicle Care 10-23
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. Just 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.
If you keep driving when your
engine is overheated, the liquids
in it can catch fire. You or others
could be badly burned. Stop your
engine if it overheats, and get out
of the vehicle until the engine
is 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. See“Driving on
Grades” underTrailer Towingon
page 9‑74.
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.

i-4 INDEX
E
E85 Fuel . . . . . . . . . . . . . . . . . . . . . . . 9-66
Electrical Equipment,Add-On . . . . . . . . . . . . . . . . . . . . . . 9-81
Electrical System Engine CompartmentFuse Block . . . . . . . . . . . . . . . . 10-39
Fuses and Circuit Breakers . . . . . . . . . . . . . . . . . . 10-39
Overload . . . . . . . . . . . . . . . . . . . 10-38
Engine
Air Cleaner/Filter . . . . . . . . . . . 10-17
Check and Service EngineSoon Lamp . . . . . . . . . . . . . . . . . . 5-12
Compartment Overview . . . . . . . 10-6
Coolant . . . . . . . . . . . . . . . . . . . . . 10-19
Coolant Heater . . . . . . . . . . . . . . . 9-36
Coolant Temperature Gauge . . . 5-9
Cooling System . . . . . . . . . . . . . 10-18
Cooling System Messages . . . 5-23
Drive Belt Routing . . . . . . . . . . . . 12-4
Exhaust . . . . . . . . . . . . . . . . . . . . . . 9-40
Fan . . . . . . . . . . . . . . . . . . . . . . . . . 10-24 Engine (cont.)
Overheating . . . . . . . . . . . . . . . . 10-22
Power Messages . . . . . . . . . . . . . 5-23
Pressure Light . . . . . . . . . . . . . . . . 5-17
Running While Parked . . . . . . . . 9-41
Starting . . . . . . . . . . . . . . . . . . . . . . . 9-35
Engine Oil Life System . . . . . . . . . . . . . . . . . .10-11
Messages . . . . . . . . . . . . . . . . . . . . 5-23
Equipment, Towing . . . . . . . . . . . . 9-78
Event Data Recorders . . . . . . . . 13-15
Exit Lighting . . . . . . . . . . . . . . . . . . . . 6-8
Extender, Safety Belt . . . . . . . . . . 3-26
Exterior Lamp Controls . . . . . . . . . 6-1
Exterior Lamps Off Reminder . . . 6-3
F
Fan Engine . . . . . . . . . . . . . . . . . . . . . . 10-24
Filter
Engine Air Cleaner . . . . . . . . . 10-17
Flash-to-Pass . . . . . . . . . . . . . . . . . . . 6-3
Flashers, Hazard Warning . . . . . . 6-5
Flat Tire . . . . . . . . . . . . . . . . . . . . . . 10-64
Flat Tire, Changing . . . .10-66, 10-75 Fluid
Automatic Transmission . . . . 10-12
Brakes . . . . . . . . . . . . . . . . . . . . . . 10-27
Four-Wheel Drive
Transfer Case . . . . . . . . . . . . . . . 9-46
Power Steering . . . . . . . . . . . . . 10-24
Washer . . . . . . . . . . . . . . . . . . . . . 10-25
Fog Lamps Bulb Replacement . . . . . . . . . . . . . 6-6
Folding Mirrors . . . . . . . . . . . . . . . . 2-13
Four-Wheel Drive . . . . . . . 10-29, 9-46
Front Axle . . . . . . . . . . . . . . . . . . . . 10-29 Locking . . . . . . . . . . . . . . . . . . . . . . . 9-55
Front Seats Adjustment . . . . . . . . . . . . . . . . . . . . 3-3
Heated . . . . . . . . . . . . . . . . . . . . . . . . 3-6
Front Storage . . . . . . . . . . . . . . . . . . . 4-1
Fuel . . . . . . . . . . . . . . . . . . . . . . . . . . . 9-64 Additives . . . . . . . . . . . . . . . . . . . . . 9-65
E85 (85% Ethanol) . . . . . . . . . . . 9-66
Filling a Portable FuelContainer . . . . . . . . . . . . . . . . . . . 9-69
Filling the Tank . . . . . . . . . . . . . . . 9-68

INDEX i-7
Lower Anchors and Tethersfor Children (LATCH
SYSTEM) . . . . . . . . . . . . . . . . . . . . 3-51
Lumbar Adjustment . . . . . . . . . . . . . 3-4 Front Seats . . . . . . . . . . . . . . . . . . . . 3-4
M
MaintenanceRecords . . . . . . . . . . . . . . . . . . . . . 11-11
Maintenance Schedule Recommended Fluids andLubricants . . . . . . . . . . . . . . . . . . . 11-8
Scheduled Maintenance . . . . . . 11-2
Transfer Case Vent Filter . . . . . 9-46
Malfunction Indicator Lamp . . . . 5-12
Manual Transmission . . . . . . . . . . 9-44 Fluid . . . . . . . . . . . . . . . . . . . . . . . . 10-15
Messages
Battery Voltage andCharging . . . . . . . . . . . . . . . . . . . . 5-21
Brake System . . . . . . . . . . . . . . . . 5-22
Door Ajar . . . . . . . . . . . . . . . . . . . . . 5-22
Engine Cooling System . . . . . . . 5-23
Engine Oil . . . . . . . . . . . . . . . . . . . . 5-23
Engine Power . . . . . . . . . . . . . . . . 5-23
Fuel System . . . . . . . . . . . . . . . . . . 5-24 Messages (cont.)
Lamp . . . . . . . . . . . . . . . . . . . . . . . . . 5-24
Ride Control System . . . . . . . . . . 5-24
Service Vehicle . . . . . . . . . . . . . . . 5-25
Tire . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-25
Transmission . . . . . . . . . . . . . . . . . 5-25
Vehicle . . . . . . . . . . . . . . . . . . . . . . . 5-21
Mirrors Automatic Dimming
Rearview . . . . . . . . . . . . . . . . . . . . 2-14
Convex . . . . . . . . . . . . . . . . . . . . . . . 2-13
Folding . . . . . . . . . . . . . . . . . . . . . . . 2-13
Power . . . . . . . . . . . . . . . . . . . . . . . . 2-13
Monitor System, Tire
Pressure . . . . . . . . . . . . . . . . . . . . 10-52
N
Navigation SystemVehicle Data Recordingand Privacy . . . . . . . . . . . . . . . 13-16
Net, Convenience . . . . . . . . . . . . . . 4-3
New Vehicle Break-In . . . . . . . . . . 9-33
O
Odometer . . . . . . . . . . . . . . . . . . . . . . . 5-8 Trip . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-8
Off-Road . . . . . . . . . . . . . . . . . . . . . . . 9-7 Driving . . . . . . . . . . . . . . . . . . . . . . . . . 9-7
Lamps . . . . . . . . . . . . . . . . . . . . . . . . . 6-6
Recovery . . . . . . . . . . . . . . . . . . . . . . 9-5
Oil Engine . . . . . . . . . . . . . . . . . . . . . . . . 10-9
Engine Oil Life System . . . . . .10-11
Messages . . . . . . . . . . . . . . . . . . . . 5-23
Pressure Light . . . . . . . . . . . . . . . . 5-17
Older Children, Restraints . . . . . 3-42
Online Owner Center . . . . . . . . . . 13-4
OnStar
®System . . . . . . . . . . . . . . . 1-19
Operation, Infotainment
System . . . . . . . . . . . . . . . . . . . . . . . . 7-2
Outlets Power . . . . . . . . . . . . . . . . . . . . . . . . . 5-5
Overheating, Engine . . . . . . . . . . 10-22