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
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.
10-30 Vehicle Care
Starter Switch Check
{WARNING
When you are doing this
inspection, the vehicle could
move suddenly. If the vehicle
moves, you or others could be
injured.
1. Before starting this check, be sure there is enough room
around the vehicle.
2. Firmly apply both the parking brake and the regular brake.
See Parking Brake
on
page 9‑51.
Do not use the accelerator
pedal, and be ready to turn off
the engine immediately if it
starts. 3. For automatic transmission
vehicles, try to start the engine
in each gear. The vehicle
should start only in P (Park) or
N (Neutral). If the vehicle starts
in any other position, contact
your dealer for service.
For manual transmission
vehicles, put the shift lever in
Neutral, push the clutch pedal
down halfway, and try to start
the engine. The vehicle should
start only when the clutch pedal
is pushed down all the way to
the floor. If the vehicle starts
when the clutch pedal is not
pushed all the way down,
contact your dealer for service.
Automatic Transmission
Shift Lock Control
System Check
{WARNING
When you are doing this
inspection, the vehicle could
move suddenly. If the vehicle
moves, you or others could be
injured.
1. Before starting this check, be sure there is enough room
around the vehicle. It should be
parked on a level surface.
2. Firmly apply the parking brake. See Parking Brake
on
page 9‑51.
Be ready to apply the regular
brake immediately if the vehicle
begins to move.
Vehicle Care 10-31
3. With the engine off, turn theignition to ON/RUN, but do
not start the engine. Without
applying the regular brake, try
to move the shift lever out of
P (Park) with normal effort. If the
shift lever moves out of P (Park),
contact your dealer for service.
Ignition Transmission
Lock Check
While parked, and with the parking
brake set, try to turn the ignition to
LOCK/OFF in each shift lever
position.
.For automatic transmission
vehicles, the ignition should turn
to LOCK/OFF only when the
shift lever is in P (Park). The
ignition key should come out
only in LOCK/OFF.
.For manual transmission
vehicles, the ignition key should
come out only in LOCK/OFF.
Contact your dealer if service is
required.
Park Brake and P (Park)
Mechanism Check
{WARNING
When you are doing this check,
the vehicle could begin to move.
You or others could be injured
and property could be damaged.
Make sure there is room in front
of the vehicle in case it begins to
roll. Be ready to apply the regular
brake at once should the vehicle
begin to move. Park on a fairly steep hill, with the
vehicle facing downhill. Keeping
your foot on the regular brake, set
the parking brake.
.To check the parking brake's
holding ability: With the engine
running and the transmission in
N (Neutral), slowly remove foot
pressure from the regular brake
pedal. Do this until the vehicle is
held by the parking brake only.
.To check the P (Park)
mechanism's holding ability:
With the engine running, shift
to P (Park). Then release the
parking brake followed by the
regular brake.
Contact your dealer if service is
required.
Vehicle Care 10-87
You would not be able to start
your vehicle, and the bad
grounding could damage the
electrical systems.
To avoid the possibility of the
vehicles rolling, set the parking
brake firmly on both vehicles
involved in the jump start
procedure. Put an automatic
transmission in P (Park) or a
manual transmission in Neutral
before setting the parking brake.
If you have a four-wheel-drive
vehicle, be sure the transfer
case is not in Neutral.
Notice: If you leave the radio or
other accessories on during the
jump starting procedure, they
could be damaged. The repairs
would not be covered by the
warranty. Always turn off the
radio and other accessories
when jump starting the vehicle. 3. Turn off the ignition on both
vehicles. Unplug unnecessary
accessories plugged into the
cigarette lighter or the accessory
power outlets. Turn off the radio
and all lamps that are not
needed. This will avoid sparks
and help save both batteries.
And it could save the radio!
4. Open the hoods and locate the batteries on both vehicles. You
will use the positive (+) battery
terminal and the remote
negative (−) jump starting
terminal to jump start your
vehicle. To access the
positive (+) battery terminal,
open the terminal cover. See
Engine Compartment Overview
on page 10‑6for more
information on the terminal
locations.
{WARNING
Using a match near a battery can
cause battery gas to explode.
People have been hurt doing this,
and some have been blinded.
Use a flashlight if you need more
light.
Be sure the batteries have
enough water. You do not need
to add water to the ACDelco
®
battery (or batteries) installed in
your new vehicle. But if a battery
has filler caps, be sure the right
amount of fluid is there. If it is low,
add water to take care of that
first. If you do not, explosive gas
could be present.
Battery fluid contains acid that
can burn you. Do not get it on
you. If you accidentally get it in
your eyes or on your skin, flush
the place with water and get
medical help immediately.
Vehicle Care 10-91
Use the following procedure to tow
the vehicle:
1. Put the transmission in P (Park)for an automatic transmission
or in 1 (First) for a manual
transmission.
2. Turn the engine off, but leave the ignition in ACC/
ACCESSORY.
3. Firmly set the parking brake.
4. Securely attach the vehicle being towed to the tow vehicle.
{WARNING
Shifting a full‐time four‐wheel‐
drive vehicle's transfer case into
N (Neutral) can cause the vehicle
to roll even if the automatic
transmission is in P (Park) or the
manual transmission is in any
gear. You or others could be
injured. Make sure the parking
brake is firmly set before the
transfer case is shifted to
N (Neutral). 5. Shift the transfer case to
N (Neutral). See Four-Wheel
Drive
on page 9‑46for the
proper procedure to select the
N (Neutral) position for the
vehicle.
6. Release the parking brake only after the vehicle being towed
is firmly attached to the tow
vehicle.
7. Make sure the ignition is in ACC/ACCESSORY.
When towing the vehicle for
extended periods of time, start the
vehicle as often as possible to
prevent battery drain. This should
only be done when the tow vehicle
is parked.
After towing, see “Shifting Out of
NEUTRAL” underFour-Wheel Drive
on page 9‑46.
Dolly Towing
Notice: Dolly towing the
vehicle will damage drivetrain
components. Do not dolly tow the
vehicle.
The vehicle cannot be dolly towed.
If the vehicle must be towed behind
another vehicle, use the dinghy
towing procedure explained
previously.