Page 265 of 410

Driving and Operating 9-81
Trailer Brake Control Wiring
Harness
The trailer brake control wiring
harness is located under the
instrument panel to the right of the
steering column. The wires are
taped to the harness that goes
to the courtesy light under the
instrument panel. The harness
has the following wires:
.Red Wire: AUX B+
.Black Wire: Ground
.Light Blue Wire: Brake Signal
.Dark Blue Wire: Trailer Brakes
Trailer Recommendations
Subtract the hitch loads from the
Cargo Weight Rating (CWR). CWR
is the maximum weight of the load
the vehicle can carry. It does not
include the weight of the people
inside, but you can figure about
68 kg (150 lbs) for each passenger.
The total cargo load must not be
more than the vehicles CWR.
Weigh the vehicle with the trailer
attached, so the GVWR or GAWR
are not exceeded. If using a
weight-distributing hitch, weigh the
vehicle without the spring bars in
place.
The best performance is obtained
by correctly spreading out the
weight of the load and choosing the
correct hitch and trailer brakes.
For more information seeTrailer
Towing on page 9‑74.
Conversions and
Add-Ons
Add-On Electrical
Equipment
Notice: Do not add anything
electrical to the vehicle unless
you check with your dealer first.
Some electrical equipment can
damage the vehicle and the
damage would not be covered
by the vehicle's warranty. Some
add-on electrical equipment can
keep other components from
working as they should.
Add-on equipment can drain the
vehicle battery, even if the vehicle is
not operating.
The vehicle has an airbag system.
Before attempting to add anything
electrical to the vehicle, see
Servicing the Airbag-Equipped
Vehicle
on page 3‑40and Adding
Equipment to the Airbag-Equipped
Vehicle on page 3‑40.
Page 266 of 410
9-82 Driving and Operating
2NOTES
Page 267 of 410

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
Page 268 of 410

10-2 Vehicle Care
Wheels and Tires
Tires . . . . . . . . . . . . . . . . . . . . . . . . 10-44
Tire Sidewall Labeling . . . . . . 10-44
Tire Designations . . . . . . . . . . . 10-46
Tire Terminology andDefinitions . . . . . . . . . . . . . . . . 10-48
Tire Pressure . . . . . . . . . . . . . . . 10-51
Tire Pressure Monitor System . . . . . . . . . . . . . . . . . . . 10-52
Tire Pressure Monitor Operation . . . . . . . . . . . . . . . . . 10-53
Tire Inspection . . . . . . . . . . . . . . 10-57
Tire Rotation . . . . . . . . . . . . . . . 10-57
When It Is Time for New Tires . . . . . . . . . . . . . . . . . . . . . . 10-58
Buying New Tires . . . . . . . . . . . 10-59
Different Size Tires and Wheels . . . . . . . . . . . . . . . . . . . 10-60
Uniform Tire Quality Grading . . . . . . . . . . . . . . . . . . . 10-61 Wheel Alignment and Tire
Balance . . . . . . . . . . . . . . . . . . . 10-62
Wheel Replacement . . . . . . . . 10-63
Tire Chains . . . . . . . . . . . . . . . . . 10-64
If a Tire Goes Flat . . . . . . . . . . 10-64
Tire Changing (H3T) . . . . . . . . 10-66
Tire Changing (H3) . . . . . . . . . 10-75
Secondary Latch System . . . 10-84
Full-Size Spare Tire . . . . . . . . 10-85
Jump Starting
Jump Starting . . . . . . . . . . . . . . 10-86
Towing
Towing the Vehicle . . . . . . . . . 10-90
Recreational Vehicle Towing . . . . . . . . . . . . . . . . . . . . 10-90
Appearance Care
Exterior Care . . . . . . . . . . . . . . . 10-92
Interior Care . . . . . . . . . . . . . . . . 10-96
General Information
For service and parts needs, visit
your dealer/retailer. You will receive
genuine parts and trained and
supported service people.
California Proposition 65
Warning
Most motor vehicles, including this
one, contain and/or emit chemicals
known to the State of California to
cause cancer and birth defects or
other reproductive harm. Engine
exhaust, many parts and systems,
many fluids, and some component
wear by-products contain and/or
emit these chemicals.
Page 269 of 410

Vehicle Care 10-3
California Perchlorate
Materials Requirements
Certain types of automotive
applications, such as airbag
initiators, seat belt pretensioners,
and lithium batteries contained in
remote keyless transmitters, may
contain perchlorate materials.
Special handling may be necessary.
For additional information, see
www.dtsc.ca.gov/hazardouswaste/
perchlorate.
Accessories and
Modifications
Adding non‐dealer/non‐retailer
accessories to the vehicle can affect
vehicle performance and safety,
including such things as airbags,
braking, stability, ride and handling,
emissions systems, aerodynamics,
durability, and electronic systems
like antilock brakes, traction control,
and stability control. Some of these
accessories could even cause
malfunction or damage not covered
by the vehicle warranty.
Damage to vehicle components
resulting from the installation or
use of non‐certified parts, including
control module modifications, isnot covered under the terms of the
vehicle warranty and may affect
remaining warranty coverage for
affected parts.
HUMMER Accessories are
designed to complement and
function with other systems on
the vehicle. Your HUMMER
dealer/retailer can accessorize the
vehicle using genuine HUMMER
Accessories. When you go to your
HUMMER dealer/retailer and ask
for HUMMER Accessories, you will
know that HUMMER-trained and
supported service technicians will
perform the work using genuine
HUMMER Accessories.
Also, see
Adding Equipment to the
Airbag-Equipped Vehicle
on
page 3‑40.
Page 270 of 410

10-4 Vehicle Care
Vehicle Checks
Doing Your Own
Service Work
{WARNING
You can be injured and the
vehicle could be damaged if you
try to do service work on a vehicle
without knowing enough about it.
.Be sure you have sufficient
knowledge, experience,
the proper replacement
parts, and tools before
attempting any vehicle
maintenance task.(Continued)
WARNING (Continued)
.Be sure to use the proper
nuts, bolts, and other
fasteners. English and
metric fasteners can be
easily confused. If the wrong
fasteners are used, parts can
later break or fall off. You
could be hurt.
If doing some of your own service
work, use the proper service
manual. It tells you much more about how to service the vehicle
than this manual can. To order the
proper service manual, see
Service
Publications Ordering Informationon
page 13‑12.
This vehicle has an airbag system.
Before attempting to do your own
service work, see Airbag System
Check on page 3‑41.
Keep a record with all parts receipts
and list the mileage and the date of
any service work performed. See
Maintenance Records
on
page 11‑11.
Page 271 of 410
Vehicle Care 10-5
Hood
To open the hood:
1. Pull the handle with this symbolon it. It is located inside the
vehicle on the lower left side of
the instrument panel. 2. Release the secondary latch on
the hood. It is located below the
front center of the hood.
3. Lift the hood.
Before closing the hood, be sure all
the filler caps are on properly. Then
pull the hood down and close it
firmly.
Page 272 of 410
10-6 Vehicle Care
Engine Compartment Overview
3.7 L L5 Engine