3. Firmly set the parking brake. SeeParking Brake on
page 3-36for more information.
4. Put the transmission in P (Park).
5. Secure the vehicle to the dolly following the
manufacturer’s instructions.
6. Use an adequate clamping device designed for
towing to ensure that the front wheels are locked
into the straight position.
7. Turn the ignition to LOCK/OFF.
If the tow vehicle will not be started or driven for six
weeks or more, remove the battery cable from
the negative terminal (post) of the battery to prevent
the battery from draining while towing.All-Wheel-Drive Vehicles
The vehicle was not designed to be towed with two
wheels on the ground. To properly tow these vehicles,
they should be placed on a platform trailer with all
four wheels off the ground.
Notice:Towing an all-wheel-drive vehicle with all
four wheels on the ground, or even with only two of
its wheels on the ground, will damage drivetrain
components. Do not tow an all-wheel-drive vehicle
with any of its wheels on the ground.
5-29
Trailer Wiring Harness
The optional heavy-duty trailer wiring package includes
a wiring harness, with a seven-pin connector at the
rear of the vehicle and a four-wire harness assembly
under the driver side of the instrument panel. The
four-wire harness assembly comes without a connector.
If the vehicle does not have a trailer hitch, the
seven-wire harness assembly with connector is taped
together and located in a frame pocket at the driver side
rear left corner of the frame.
If the vehicle has a trailer hitch, the seven-wire harness
assembly with connector is attached to a bracket on
the hitch platform. In both cases, the seven-wire harness
has a connector and includes a 30-amp feed wire.
The seven-wire harness connector contains the following
trailer circuits:
•Light Green: Back-up Lamps (10A fuse)**
•White: Ground
•Dark Blue: Trailer Brake Signal
•Dark Green: Right Rear Stop and Turn Signal*
•Red/Black Stripe: Battery Feed (30A Fuse)
•Brown: Trailer Park Lamp Supply Voltage
(15A fuse)**
•Yellow: Left Rear Stop and Turn Signal *
The four-wire harness (without connector) contains the
following circuits:
•Black: Ground
•Red/White: Battery Feed
•Dark Blue: Trailer Brake Signal
•Light Blue: CHMSL/Stoplamp Supply Voltage
* If the vehicle is a cutaway with trailer provisions, a
15 amp fuse will be shared for both left/stop trailer turn
and right/stop trailer turn signals. However, the
cutaway lighting connector will have a 10 amp fuse for
each signal.
** If the vehicle is a cutaway with trailer provisions, a
15 amp fuse will be shared for trailer park lamps
and cutaway rear lighting connector park lamps. Also, a
10 amp fuse will be shared for trailer back-up lamps
and cutaway rear lighting connector back-up lamps.
5-42
Service............................................................6-3
Accessories and Modifications..........................6-3
California Proposition 65 Warning.....................6-4
California Perchlorate Materials Requirements.....6-4
Doing Your Own Service Work.........................6-4
Adding Equipment to the Outside of
the Vehicle.................................................6-5
Fuel................................................................6-5
Gasoline Octane............................................6-6
Gasoline Specifications....................................6-6
California Fuel...............................................6-6
Additives.......................................................6-7
Fuel E85 (85% Ethanol)..................................6-8
Fuels in Foreign Countries...............................6-9
Filling the Tank............................................6-10
Filling a Portable Fuel Container.....................6-12
Checking Things Under the Hood....................6-12
Hood Release..............................................6-13
Engine Compartment Overview.......................6-14
Engine Oil...................................................6-15
Engine Oil Life System..................................6-18
Engine Air Cleaner/Filter................................6-20
Automatic Transmission Fluid
(4-Speed Transmission)..............................6-21
Automatic Transmission Fluid
(6-Speed Transmission)..............................6-24Cooling System............................................6-28
Engine Coolant.............................................6-29
Engine Overheating.......................................6-35
Engine Fan Noise.........................................6-37
Power Steering Fluid.....................................6-38
Windshield Washer Fluid................................6-39
Brakes........................................................6-40
Battery........................................................6-43
Jump Starting...............................................6-44
All-Wheel Drive.............................................
.6-49
Rear Axle.......................................................6-50
Front Axle......................................................6-50
Noise Control System.....................................6-51
Tampering with Noise Control System
Prohibited.................................................6-51
Bulb Replacement..........................................6-53
Halogen Bulbs..............................................6-53
Headlamps..................................................6-53
Front Turn Signal, Sidemarker and
Parking Lamps..........................................6-55
Center High-Mounted Stoplamp (CHMSL).........6-56
Taillamps.....................................................6-56
License Plate Lamp......................................6-58
Replacement Bulbs.......................................6-58
Windshield Wiper Blade Replacement..............6-59
Section 6 Service and Appearance Care
6-1
A. Battery. SeeBattery on page 6-43.
B. Radiator Pressure Cap. SeeCooling System on
page 6-28.
C. Coolant Recovery Tank. SeeCooling System on
page 6-28.
D. Automatic Transmission Fluid Dipstick. See
“Checking the Fluid Level” underAutomatic
Transmission Fluid (4-Speed Transmission)
on page 6-21orAutomatic Transmission Fluid
(6-Speed Transmission) on page 6-24.
E. Engine Oil Fill Cap. See “When to Add Engine Oil”
underEngine Oil on page 6-15.
F. Engine Oil Dipstick. See “Checking Engine Oil”
underEngine Oil on page 6-15.
G. Engine Air Cleaner/Filter. SeeEngine Air
Cleaner/Filter on page 6-20.
H. Power Steering Fluid Reservoir. SeePower Steering
Fluid on page 6-38.
I. Brake Master Cylinder Reservoir. See “Brake Fluid”
underBrakes on page 6-40.
J. Windshield Washer Fluid Reservoir. See “Adding
Washer Fluid” underWindshield Washer Fluid
on page 6-39.Engine Oil
For diesel engine vehicles, see “Engine Oil” in the
DURAMAX®Diesel manual.
Checking Engine Oil
It is a good idea to check the engine oil level at each
fuel fill. In order to get an accurate reading, the oil must
be warm and the vehicle must be on level ground.
The engine oil dipstick handle is a yellow loop.
SeeEngine Compartment Overview on page 6-14
for the location of the engine oil dipstick.
1. Turn off the engine and give the oil several minutes
to drain back into the oil pan. If this is not done, the
oil dipstick might not show the actual level.
2. Pull out the dipstick and clean it with a paper towel
or cloth, then push it back in all the way. Remove it
again, keeping the tip down, and check the level.
6-15
Replacing Brake System Parts
The braking system on a vehicle is complex. Its many
parts have to be of top quality and work well together if
the vehicle is to have really good braking. The vehicle
was designed and tested with top-quality brake parts.
When parts of the braking system are replaced — for
example, when the brake linings wear down and new
ones are installed — be sure to get new approved
replacement parts. If this is not done, the brakes might
not work properly. For example, if someone puts in
brake linings that are wrong for the vehicle, the balance
between the front and rear brakes can change — for the
worse. The braking performance expected can change in
many other ways if the wrong replacement brake parts
are installed.
Battery
Refer to the replacement number on the original battery
label when a new battery is needed. SeeEngine
Compartment Overview on page 6-14for battery location.
{DANGER:
Battery posts, terminals, and related accessories
contain lead and lead compounds, chemicals
known to the State of California to cause cancer
and reproductive harm. Wash hands after handling.
6-43
Vehicle Storage
{WARNING:
Batteries have acid that can burn you and gas that
can explode. You can be badly hurt if you are not
careful. SeeJump Starting on page 6-44for tips
on working around a battery without getting hurt.
Infrequent Usage: Remove the black, negative (−) cable
from the battery to keep the battery from running down.
Extended Storage: Remove the black, negative (−) cable
from the battery or use a battery trickle charger.
Jump Starting
If the vehicle battery has run down, you may want to use
another vehicle and some jumper cables to start your
vehicle. Be sure to use the following steps to do it safely.
{WARNING:
Batteries can hurt you. They can be dangerous
because:
•They contain acid that can burn you.
•They contain gas that can explode or ignite.
•They contain enough electricity to burn you.
If you do not follow these steps exactly, some or
all of these things can hurt you.
6-44
Notice:Ignoring these steps could result in costly
damage to the vehicle that would not be covered
by the warranty.
Trying to start the vehicle by pushing or pulling it
will not work, and it could damage the vehicle.
1. Check the other vehicle. It must have a 12-volt
battery with a negative ground system.
Notice:If the other vehicle’s system is not a 12-volt
system with a negative ground, both vehicles can
be damaged. Only use vehicles with 12-volt systems
with negative grounds to jump start your vehicle.
2. Get the vehicles close enough so the jumper cables
can reach, but be sure the vehicles are not touching
each other. If they are, it could cause a ground
connection you do not want. 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 N (Neutral) before setting the parking brake.
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 outlet. 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!
6-45
4. Open the hoods and locate the positive (+) and
negative (−) terminal locations of the other vehicle.
Your vehicle has a remote positive (+) jump
starting terminal and a remote negative (−) jump
starting terminal. You should always use these
remote terminals instead of the terminals on the
battery.
The remote positive (+) terminal is located behind
a red plastic cover near the engine accessory
drive bracket on the driver’s side of the engine
compartment, below the alternator. To uncover the
remote positive (+) terminal, open the red plastic
cover.
The remote negative (−) terminal is located on
the engine drive bracket on all V8 engines and is
marked GND (Ground).
On V6 engines the remote negative (−) terminal is
located on a tab attached to the engine accessory
drive bracket and is marked GND (Ground).
{WARNING:
Using an open flame 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 battery has enough water. You do not
need to add water to the battery 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.
6-46