transmission HUMMER H3 2010 Service Manual

Driving and Operating 9-49
5. Simultaneously press andhold the Four-Wheel High and
Four-Wheel-Low Lock buttons
for 10 seconds. The Neutral light
will come on when the transfer
case shift to Neutral is complete.
6. Press and hold the regular brake pedal and shift the transmission
to R (Reverse), then shift the
transmission to D (Drive) for
an automatic transmission,
or 1 (First) for vehicles have a
manual transmission and then
let out the clutch. This is to
ensure the transfer case is in
Neutral. If not, repeat this
procedure starting at Step 3.
7. Turn the engine off. 8. Place the transmission shift
lever in P (Park) for an automatic
transmission, or 1 (First) for
vehicles that have a manual
transmission.
9. Turn the ignition to LOCK/OFF.
Shifting Out of Neutral
To shift out of Neutral:
1. Set the parking brake and apply the regular brake pedal.
2. Shift the transmission to N (Neutral) for an automatic
transmission, or press the clutch
pedal for vehicles that have a
manual transmission. Then turn
the ignition to ON/RUN but do
not start the engine. 3. Press the button for the
desired transfer case shift
position (Four-Wheel High,
Four-Wheel-High Lock or
Four-Wheel-Low Lock).
After the transfer case has
shifted out of Neutral the light
will go out.
4. Release the parking brake.
Notice: Shifting the transmission
into gear before the indicator
light stops flashing could cause
damage to the transfer case.
Always wait until the indicator
light stops flashing before putting
the transmission back in gear.
5. You may start the engine and shift the transmission to the
desired position.

9-52 Driving and Operating
The stability system hydraulic brake
control module increases brake
pressure at each corner of the
vehicle until the ABS activates.
Minor brake pedal pulsations or
pedal movement during this time
is normal and the driver should
continue to apply the brake pedal
as the driving situation dictates.
The brake assist feature will
automatically disengage when
the brake pedal is released or
brake pedal pressure is quickly
decreased.
Hill Start Assist (HSA)
This vehicle has a Hill Start Assist
(HSA) feature, which may be useful
when the vehicle is stopped on a
grade. This feature is designed to
prevent the vehicle from rolling,
either forward or rearward, during
vehicle drive off. After the vehicle
is stopped on an incline, quickly
push the brake pedal to the floor
to activate Hill Start Assist.When the system activates, a
chime will sound and the HSA ON
message will be displayed. The
brakes will automatically be held
for a maximum of two seconds
while the driver switches from
applying the brakes to pushing
the accelerator pedal. When Hill
Start Assist is active, the driver
might experience a
“hard brake
pedal.” This is normal and does
not affect safe brake operation.
After activation, the system will
automatically disengage when the
accelerator pedal is pressed. Do
not turn off the ignition while this
feature is active. The Hill Start
Assist feature may not disengage
fully if the ignition is turned off.
The system will not activate with
the transmission in P (Park), when
traveling down a steep grade in a
drive gear, or if the vehicle is facing
uphill with the transmission in
R (Reverse).
Ride Control Systems
Traction Control
System (TCS)
The vehicle has a Traction Control
System (TCS) that limits wheel
spin. This is especially useful in
slippery road conditions. The
system operates only if it senses
that any of the wheels are spinning
or beginning to lose traction. When
this happens, TCS reduces engine
power. The system may be heard
or felt while it is working. This is
normal and does not mean there is
a problem with the vehicle.
TCS can operate on dry roads
under some conditions. When
this happens, the system may be
heard working or a reduction in
acceleration may be noticed. This
is normal and does not mean there
is a problem with the vehicle.

Driving and Operating 9-53
Examples of these conditions
include hard acceleration in a turn,
an abrupt upshift or downshift of the
transmission or driving on rough
roads.
If cruise control is being used when
TCS begins to limit wheel spin,
the cruise control automatically
disengages. The cruise control
can be re-engaged when road
conditions allow. SeeCruise Control
on page 9‑57for more information.
TRACTION FAILED appears on the
Driver information Center (DIC)
when a TCS or antilock brake
system problem has been detected
and the vehicle needs service.
When this message is on, the
system will not limit wheel spin.
Adjust your driving accordingly.
See Driver Information Center (DIC)
on page 5‑18for more information.
It is recommended to leave the
system on for normal driving
conditions, but it may be necessary
to turn the system off if the vehicle
is stuck in sand, mud, ice, or snow, and it is necessary to
“rock”the
vehicle to attempt to free it. See If
the Vehicle is Stuck
on page 9‑26for more information.
To turn the system off, press and
release the TCS/StabiliTrak button.
When TCS has been turned off, this
light comes on steady and TRAC
OFF appears on the DIC. This light
flashes when TCS is active.
Press and release the
TCS/StabiliTrak button again to
turn the system back on. The TRAC
OFF message then goes off. TCS automatically comes on
whenever the vehicle is started and
resets itself at each ignition cycle.
Adding non‐dealer/non‐retailer
accessories can affect the vehicle's
performance. See
Accessories and
Modifications on page 10‑3.
StabiliTrak System
The vehicle has a vehicle stability
enhancement system called
StabiliTrak. It is an advanced
computer controlled system that
assists the driver with directional
control of the vehicle in difficult
driving conditions.
StabiliTrak activates when the
computer senses a difference
between the intended path and the
direction the vehicle is actually
traveling. StabiliTrak selectively
applies braking pressure at any
one of the vehicle's brakes to assist
the driver with keeping the vehicle
on the intended path.

9-60 Driving and Operating
Ending Cruise Control
To turn off the cruise control, do
one of the following:
.Step lightly on the brake pedal.
.Move the cruise control switch
to
9.
.Lightly tap or press the clutch,
if the vehicle has a manual
transmission.
Erasing Speed Memory
The cruise control set speed
memory is erased, when the cruise
control or the ignition is turned off.
Object Detection
Systems
Rear Vision
Camera (RVC)
Vehicles with the rear vision camera
system are designed to help the
driver while the vehicle is backing
up. The area behind the vehicle is
displayed on the screen in the
inside rear view mirror. Read this
entire section before using the
camera system.
When the key is in the ON/RUN
position and the driver shifts the
vehicle into R (Reverse), the video
image appears from inside the rear
view mirror. Once the vehicle is
shifted out of R (Reverse), the
image disappears. The display may have a guideline
overlay that can help the driver align
the vehicle when backing into a
parking spot.
Turning the Rear Vision Camera
System On or Off
To turn off the rear vision camera
system, press and hold
z, located
on the inside rearview mirror, until
the left indicator light turns off. The
rear camera vision display is now
disabled.
To turn the rear vision camera
system on again, press and
hold
zuntil the left indicator light
illuminates. The rear vision camera
system display is now enabled and
the display will appear in the mirror
normally.

Driving and Operating 9-71
With the added weight, the engine,
transmission, wheel assemblies and
tires are forced to work harder and
under greater loads. The trailer also
adds wind resistance, increasing
the pulling requirements. For safe
trailering, correctly use the proper
trailering equipment.
The following information has
important trailering tips and rules
for your safety and that of your
passengers. Read this section
carefully before pulling a trailer.
Pulling A Trailer
Here are some important points:
.There are many laws, including
speed limit restrictions that apply
to trailering. Check for legal
requirements with state or
provincial police.
.Consider using a sway control.
See“Hitches” later in this
section.
.Do not tow a trailer at all during
the first 800 km (500 miles) the
new vehicle is driven. The
engine, axle or other parts could
be damaged.
.Then, during the first 800 km
(500 miles) that a trailer is
towed, do not drive over 80 km/h
(50 mph) and do not make starts
at full throttle. This helps the
engine and other parts of the
vehicle wear in at the heavier
loads.
.Vehicles with an automatic
transmission can tow in
D (Drive). Use a lower gear if
the transmission shifts too often.
For vehicles with a manual
transmission, it is better not to
use the highest gear.
.This vehicle has a Hill Start
Assist feature, which may be
useful when the vehicle is
stopped on a grade. See Hill
Start Assist (HSA)
on page 9‑52for more information.
.Do not drive faster than the
maximum posted speed for
trailers.
Driving with a Trailer
Towing a trailer requires experience.
Get familiar with handling and
braking with the added trailer
weight. The vehicle is now longer
and not as responsive as the
vehicle is by itself.
Check all trailer hitch parts and
attachments, safety chains,
electrical connectors, lamps, tires
and mirror adjustments. If the trailer
has electric brakes, start the vehicle
and trailer moving and then apply
the trailer brake controller by hand
to be sure the brakes are working.
During the trip, check occasionally
to be sure that the load is secure,
and the lamps and trailer brakes are
working properly.

9-72 Driving and Operating
Towing with a Stability Control
System
When towing, the sound of the
stability control system might be
heard. The system is reacting to the
vehicle movement caused by the
trailer, which mainly occurs during
cornering. This is normal when
towing heavier trailers.
Following Distance
Stay at least twice as far behind the
vehicle ahead as you would when
driving the vehicle without a trailer.
This can help to avoid situations
that require heavy braking and
sudden turns.
Passing
More passing distance is needed
when towing a trailer. Because the
rig is longer, it is necessary to go
much farther beyond the passed
vehicle before returning to the lane.
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 won't strike soft
shoulders, curbs, road signs, trees
or other objects. Avoid jerky or
sudden maneuvers. Signal well in
advance.
Turn Signals When Towing a
Trailer
The arrows on the instrument panel
flash whenever signaling a turn or
lane change. Properly hooked up,
the trailer lamps also flash, telling
other drivers the vehicle is turning,
changing lanes or stopping.
When towing a trailer, the arrows on
the instrument panel flash for turns
even if the bulbs on the trailer are
burned out. For this reason you
may think other drivers are seeing
the signal when they are not. 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 before starting down a
long or steep downgrade. If the
transmission is not shifted down, the
brakes might have to be used so
much that they would get hot and no
longer work well.

Driving and Operating 9-73
Vehicles with an automatic
transmission 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. For vehicles with a
manual transmission, it is better not
to use the highest gear.
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. For vehicles with manualtransmissions, let the engine run
while parked, preferably on level
ground, with the transmission out of
gear and the parking brake applied,
for a few minutes before turning the
engine off. If the overheat warning
comes on, see
Engine Overheating
on page 10‑22.
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. If parking the rig on a hill:
1. Press the brake pedal, but do
not shift into P (Park) yet for
vehicles with an automatic
transmission, or into gear
for vehicles with a manual
transmission. Turn the wheels
into the curb if facing downhill
or into traffic if facing uphill.
2. Have someone place chocks under the trailer wheels.
3. When the wheel chocks are in place, release the brake pedal
until the chocks absorb the load.
4. Reapply the brake pedal. Then apply the parking brake and shift
into P (Park) for vehicles with an
automatic transmission or into
gear for vehicles with a manual
transmission.
5. Release the brake pedal.

9-74 Driving and Operating
Leaving After Parking on a Hill
1. Apply and hold the brake pedalwhile you:
.start the engine,
.shift into a gear, and
.release the parking brake.
2. Let up on the brake pedal.
3. Drive slowly until the trailer is clear of the chocks.
4. Stop and have someone pick up and store the chocks.
Maintenance When Trailer
Towing
The vehicle needs service more
often when pulling a trailer. See this
manual's Maintenance Schedule
or Index for more information.
Things that are especially important
in trailer operation are automatic
transmission fluid, engine oil, axle lubricant, belts, cooling system and
brake system. It is a good idea to
inspect these before and during
the trip.
Check periodically to see that all
hitch nuts and bolts are tight.
Engine Cooling When Trailer
Towing
The cooling system may temporarily
overheat during severe operating
conditions. See
Engine Overheating
on page 10‑22.
Trailer Towing
Three important considerations
have to do with weight:
.The weight of the trailer.
.The weight of the trailer tongue.
.The total weight on the vehicle's
tires.
Weight of the Trailer
How heavy can a trailer safely be?
Speed, altitude, road grades,
outside temperature, special
equipment, and the amount of
tongue weight the vehicle can carry
must be considered. See “Weight of
the Trailer Tongue” later in this
section for more information.
Maximum trailer weight is calculated
assuming only the driver is in the
tow vehicle and it has all the
required trailering equipment.
The weight of additional optional
equipment, passengers and cargo in
the tow vehicle must be subtracted
from the maximum trailer weight.
Use the following chart to determine
how much a vehicle can weigh,
based on the vehicle model and
options.

Driving and Operating 9-75
VehicleAxle Ratio Maximum Trailer Weight *GCWR
H3 3.7L L5 Engine, Automatic
Transmission 4.56
4,500 lbs (2 041 kg) 9,500 lbs (4 309 kg)
3.7L L5 Engine, Manual
Transmission 4.56
3,000 lbs (1 361 kg) 8,000 lbs (3 629 kg)
5.3L V8 Engine, Automatic
Transmission 4.10
6,000 lbs (2 721 kg) 11,400 lbs (5 171 kg)
H3T 3.7L L5 Engine, Automatic
Transmission 4.56
4,400 lbs (1 996 kg) 9,500 lbs (4 309 kg)
3.7L L5 Engine, Manual
Transmission 4.56
2,900 lbs (1 315 kg) 8,000 lbs (3 629 kg)
5.3L V8 Engine, Automatic
Transmission 4.10
5,900 lbs (2 676 kg) 11,400 lbs (5 171 kg)
*The Gross Combination Weight Rating (GCWR) in the total allowable weight of the completely loaded vehicle and
trailer including any passengers, cargo, equipment and conversions. The GCWR for the vehicle should not be
exceeded.

Vehicle Care 10-1
Vehicle Care
General Information
General Information . . . . . . . . . . 10-2
California Proposition65 Warning . . . . . . . . . . . . . . . . . 10-2
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 . . . . . . . . . . . . . . . . . . . 10-9
Engine Oil Life System . . . . . 10-11
Automatic Transmission Fluid . . . . . . . . . . . . . . . . . . . . . . 10-12
Manual Transmission Fluid . . . . . . . . . . . . . . . . . . . . . . 10-15 Hydraulic Clutch . . . . . . . . . . . . 10-16
Engine Air Cleaner/Filter . . . . 10-17
Cooling System . . . . . . . . . . . . 10-18
Engine Coolant . . . . . . . . . . . . . 10-19
Engine Overheating . . . . . . . . 10-22
Engine Fan . . . . . . . . . . . . . . . . . 10-24
Power Steering Fluid . . . . . . . 10-24
Washer Fluid . . . . . . . . . . . . . . . 10-25
Brakes . . . . . . . . . . . . . . . . . . . . . 10-26
Brake Fluid . . . . . . . . . . . . . . . . . 10-27
Battery . . . . . . . . . . . . . . . . . . . . . 10-28
Four-Wheel Drive . . . . . . . . . . . 10-29
Front Axle . . . . . . . . . . . . . . . . . . 10-29
Rear Axle . . . . . . . . . . . . . . . . . . 10-29
Starter Switch Check . . . . . . . 10-30
Automatic Transmission Shift
Lock Control System
Check . . . . . . . . . . . . . . . . . . . . . 10-30
Ignition Transmission Lock Check . . . . . . . . . . . . . . . . . . . . . 10-31
Park Brake and P (Park) Mechanism Check . . . . . . . . 10-31
Wiper Blade Replacement . . . . . . . . . . . . . . 10-32
Headlamp Aiming
Headlamp Aiming . . . . . . . . . . 10-33
Bulb Replacement
Bulb Replacement . . . . . . . . . . 10-35
Halogen Bulbs . . . . . . . . . . . . . . 10-35
Headlamps . . . . . . . . . . . . . . . . . 10-35
Taillamps, Turn Signal,Stoplamps, and Back-Up
Lamps (H3) . . . . . . . . . . . . . . . 10-35
Taillamps, Turn Signal, Stoplamps, and Back-Up
Lamps (H3T) . . . . . . . . . . . . . . 10-36
License Plate Lamp . . . . . . . . 10-37
Replacement Bulbs . . . . . . . . . 10-37
Electrical System
Electrical System Overload . . . . . . . . . . . . . . . . . . 10-38
Fuses and Circuit Breakers . . . . . . . . . . . . . . . . . . 10-39
Engine Compartment Fuse Block . . . . . . . . . . . . . . . . . . . . . 10-39