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City Driving
One of the biggest problems with city streets is the
amount of traffic on them. You will want to watch out for
what the other drivers are doing and pay attention to
traffic signals.Here are ways to increase your safety in city driving:
Know the best way to get to where you are
going. Get a city map and plan your trip into
an unknown part of the city just as you would for a
cross-country trip.
Try to use the freeways that rim and crisscross
most large cities. You will save time and energy.
SeeFreeway Driving on page 4-33.
Treat a green light as a warning signal. A traffic
light is there because the corner is busy enough
to need it. When a light turns green, and just before
you start to move, check both ways for vehicles
that have not cleared the intersection or may
be running the red light.
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Freeway Driving
Mile for mile, freeways — also called thruways, parkways,
expressways, turnpikes, or superhighways — are the
safest of all roads. But they have their own special rules.The most important advice on freeway driving is: Keep
up with traffic and keep to the right. Drive at the
same speed most of the other drivers are driving.
Too-fast or too-slow driving breaks a smooth traffic ow.
Treat the left lane on a freeway as a passing lane.
At the entrance, there is usually a ramp that leads to the
freeway. If you have a clear view of the freeway as you
drive along the entrance ramp, you should begin to check
traffic. Try to determine where you expect to blend with
the ow. Try to merge into the gap at close to the
prevailing speed. Switch on your turn signal, check your
mirrors, and glance over your shoulder as often as
necessary. Try to blend smoothly with the traffic ow.
Once you are on the freeway, adjust your speed to the
posted limit or to the prevailing rate if it is slower.
Stay in the right lane unless you want to pass.
Before changing lanes, check your mirrors. Then use
your turn signal.
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Making Turns
Notice:Making very sharp turns while trailering
could cause the trailer to come in contact with the
vehicle. Your vehicle could be damaged. Avoid
making very sharp turns while trailering.
When you’re turning with a trailer, make wider turns than
normal. Do this so your 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 your instrument panel will ash whenever
you signal a turn or lane change. Properly hooked up,
the trailer lamps will also ash, telling other drivers
you’re about to turn, change lanes or stop.
When towing a trailer, the arrows on your instrument
panel will ash for turns even if the bulbs on the trailer
are burned out. Thus, you may think drivers behind
you are seeing your signal when they are not. It’s
important to check occasionally to be sure the trailer
bulbs are still working.
Driving On Grades
Reduce speed and shift to a lower gearbeforeyou start
down a long or steep downgrade. If you don’t shift
down, you might have to use your brakes so much that
they would get hot and no longer work well.
You can tow in DRIVE (D). You may want to shift the
transmission to THIRD (3) or a lower gear, under heavy
loads or hilly conditions.
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 you turn your
engine off immediately after towing at high altitude
on steep uphill grades, your 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 PARK (P) for a
few minutes before turning the engine off. If you do get
the overheat warning, seeEngine Overheating on
page 5-27.
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Trailer Wiring Harness
Your vehicle is equipped with a seven-wire trailer towing
harness. This harness has a seven-pin universal
heavy-duty trailer connector that is attached to a bracket
on the hitch platform.The seven-wire harness contains the following trailer
circuits:
Yellow: Left Stop/Turn Signal
Dark Green: Right Stop/Turn Signal
Brown: Running Lamps
White: Ground
Light Green: Back-up Lamps
Dark Blue: Electric Brakes
Red: Battery Feed (The chassis wiring ring terminal
must be fastened to a stud on the underhood
electrical center before the trailer feed will become
active.)
If you need to tow a light-duty trailer with a standard
four-way round pin connector, an adapter connector is
available from your dealer.
Your vehicle is also equipped with wiring for an electric
trailer brake controller. These wires are located
inside the vehicle on the driver’s side under the
instrument panel. These wires should be connected to
an electric trailer brake controller by your dealer or
a quali ed service center.
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Service............................................................5-3
Doing Your Own Service Work.........................5-4
Adding Equipment to the Outside of Your
Vehicle......................................................5-5
Fuel................................................................5-5
Gasoline Octane............................................5-5
Gasoline Speci cations....................................5-5
California Fuel...............................................5-5
Additives.......................................................5-6
Fuels in Foreign Countries...............................5-7
Filling Your Tank............................................5-7
Filling a Portable Fuel Container.......................5-9
Checking Things Under the Hood....................5-10
Hood Release..............................................5-10
Engine Compartment Overview.......................5-12
Engine Oil...................................................5-16
Engine Oil Life System..................................5-19
Engine Air Cleaner/Filter................................5-20
Automatic Transmission Fluid.........................5-22
Engine Coolant.............................................5-24
Radiator Pressure Cap..................................5-27
Engine Overheating.......................................5-27
Cooling System............................................5-29
Engine Fan Noise.........................................5-34
Power Steering Fluid.....................................5-35
Windshield Washer Fluid................................5-36Brakes........................................................5-37
Battery........................................................5-40
Jump Starting...............................................5-41
All-Wheel Drive..............................................5-46
Rear Axle.......................................................5-46
Front Axle......................................................5-47
Bulb Replacement..........................................5-48
Halogen Bulbs..............................................5-48
Headlamps, Front Turn Signal, Sidemarker,
and Parking Lamps....................................5-49
Taillamps and Turn Signal Lamps...................5-49
Replacement Bulbs.......................................5-50
Windshield Wiper Blade Replacement..............5-51
Tires..............................................................5-53
Tire Sidewall Labelling...................................5-54
Tire Terminology and De nitions.....................5-57
In ation - Tire Pressure.................................5-59
Tire Inspection and Rotation...........................5-60
When It Is Time for New Tires.......................5-62
Buying New Tires.........................................5-62
Uniform Tire Quality Grading..........................5-63
Wheel Alignment and Tire Balance..................5-64
Wheel Replacement......................................5-65
Tire Chains..................................................5-66
Accessory In ator.........................................5-67
Section 5 Service and Appearance Care
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Headlamps, Front Turn Signal,
Sidemarker, and Parking Lamps
To replace a bulb, do the following:
1. Open the hood. SeeHood Release on page 5-10
for more information.
2. Remove the grille by grasping and pulling it
forward.
3. Lift the inner quick release clips.
4. Pull the headlamp assembly away from the vehicle.
5. Remove the cover from the headlamp bulb.
6. Disconnect the wiring harness.
7. Remove the bulb socket by turning it
counterclockwise. Pull the bulb from the socket.
8. Replace the bulb.
9. Reinstall by reversing Steps 1 through 6.
Taillamps and Turn Signal Lamps
To replace a taillamp or turn signal bulb, do the
following:
1. Open the liftgate. SeeLiftgate/Liftglass on
page 2-13for more information.
2. Remove the two
screws from the
taillamp assembly.
3. Pull the taillamp assembly away from the vehicle.
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4. Unclip the wiring harness (A) and remove the
three socket retaining screws (B).
5. Remove the socket by releasing the retaining tabs.
6. Holding the socket, pull the bulb to release it
from the socket.
7. Reinstall by reversing Steps 1 through 6.
Replacement Bulbs
Exterior Lamp Bulb Number
Front Parking and Sidemarker
Lamp194
Front Turn Signal Lamp 3757 A
Halogen Headlamps
High-Beam 9005 HB3
Low-Beam 9006 HB4
Rear Turn Signal and Taillamps 3057
For replacement bulbs not listed here, contact your
dealer.
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Fuses Usage
25 Blank
26 Blank
27OnStar
®Overhead Battery, OnStar®
System
28 Sunroof
29 Rainsense™ Wipers
30 Parking Lamps
31 Truck Body Controller Accessory
32 Truck Body Controller 5
33 Front Wipers
34 Vehicle Stop
35 Transmission Control Module
36 Heat Ventilation Air Conditioning B
37 Front Parking Lamps
38 Left Turn Signal
Fuses Usage
39 Heat Ventilation Air Conditioning I
40 Truck Body Controller 4
41 Radio
42 Trailer Park
43 Right Turn Signal
44 Heat Ventilation Air Conditioning
45 Rear Fog Lamps
46 Auxiliary Power 1
47 Ignition 0
48 Four-Wheel Drive
49 Blank
50 Truck Body Controller Ignition
51 Brakes
52 Truck Body Controller Run
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