2006 GMC SIERRA service

Before Leaving on a Long Trip
Make sure you are ready. Try to be well rested. If you
must start when you are not fresh — such as after a day’s
work — do not plan to make too many miles that rst part
of the journey. Wear comfortable clothing and shoes you
can easily drive in.
Is your vehicle ready for a long trip? If you keep it
serviced and maintained, it is ready to go. If it needs
service, have it done before starting out. Of course,
you will nd experienced and able service experts in
GM dealerships all across North America. They will be
ready and willing to help if you need it.Here are some things you can check before a trip:Windshield Washer Fluid:Is the reservoir full?
Are all windows clean inside and outside?
Wiper Blades:Are they in good shape?
Fuel, Engine Oil, Other Fluids:Have you checked
all levels?
Lamps:Are they all working? Are the lenses clean?
Tires:They are vitally important to a safe,
trouble-free trip. Is the tread good enough for
long-distance driving? Are the tires all inated
to the recommended pressure?
Weather Forecasts:What is the weather outlook
along your route? Should you delay your trip a short
time to avoid a major storm system?
Maps:Do you have up-to-date maps?
4-38

Highway Hypnosis
Is there actually such a condition as highway hypnosis?
Or is it just plain falling asleep at the wheel? Call it
highway hypnosis, lack of awareness, or whatever.
There is something about an easy stretch of road with
the same scenery, along with the hum of the tires on the
road, the drone of the engine, and the rush of the wind
against the vehicle that can make you sleepy. Do not let it
happen to you! If it does, your vehicle can leave the road
in less than a second, and you could crash and be
injured.
What can you do about highway hypnosis? First, be
aware that it can happen.Then here are some tips:Make sure your vehicle is well ventilated, with a
comfortably cool interior.
Keep your eyes moving. Scan the road ahead and to
the sides. Check your mirrors and your instruments
frequently.
If you get sleepy, pull off the road into a rest, service,
or parking area and take a nap, get some exercise,
or both. For safety, treat drowsiness on the highway
as an emergency.
4-39

Towing
Towing Your Vehicle
Consult your dealer or a professional towing service
if you need to have your disabled vehicle towed.
SeeRoadside Assistance Program on page 7-6.
If you want to tow your vehicle behind another vehicle
for recreational purposes (such as behind a motorhome),
see “Recreational Vehicle Towing” following.
Recreational Vehicle Towing
Recreational vehicle towing means towing your vehicle
behind another vehicle – such as behind a motorhome.
The two most common types of recreational vehicle
towing are known as dinghy towing, towing your vehicle
will all four wheels on the ground, and dolly towing,
towing your vehicle with two wheels on the ground
and two wheels up on a device known as a “dolly”.
With the proper preparation and equipment, many
vehicles can be towed in these ways. See “Dinghy
Towing” and “Dolly Towing” following.Here are some important things to consider before you
do recreational vehicle towing:
What’s the towing capacity of the towing vehicle?
Be sure you read the tow vehicle manufacturer’s
recommendations.
How far will you tow? Some vehicles have
restrictions on how far and how long they can tow.
Do you have the proper towing equipment? See your
dealer or trailering professional for additional advice
and equipment recommendations.
Is your vehicle ready to be towed? Just as you would
prepare your vehicle for a long trip, you’ll want to
make sure your vehicle is prepared to be towed.
SeeBefore Leaving on a Long Trip on page 4-38.
Dinghy Towing
Two-Wheel-Drive Vehicles
Notice:If you tow your vehicle with all four wheels
on the ground, the drivetrain components could be
damaged. The repairs would not be covered by your
warranty. Do not tow your vehicle with all four wheels
on the ground.
Two-wheel-drive vehicles should not be towed
with all four wheels on the ground. Two-wheel-drive
transmissions have no provisions for internal lubrication
while being towed.
4-62

When You Are Ready to Leave After
Parking on a Hill
1. Apply your regular brakes and hold the pedal down
while you:
Start your engine
Shift into a gear
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
Your vehicle will need service more often when you’re
pulling a trailer. SeeScheduled Maintenance (Gasoline
Engine) on page 6-4for more information. Things that
are especially important in trailer operation are automatic
transmission uid (don’t overll), engine oil, axle
lubricant, belt, cooling system and brake system. Each of
these is covered in this manual, and the Index will help
you nd them quickly. If you’re trailering, it’s a good idea
to review these sections before you start your trip.
Check periodically to see that all hitch nuts and bolts
are tight.
Trailer Wiring Harness
Your vehicle is equipped with one of the following wiring
harnesses for towing a trailer or hauling a slide-in
camper.
Basic Trailer Wiring
All regular, extended cab and crew cab pickups have an
eight-wire trailer towing harness.
For vehicles not equipped with heavy duty trailering, the
harness is clipped to the vehicle’s frame behind the spare
tire mount. The harness requires the installation of a
trailer connector, which is available through your dealer.
4-92

Electric Brake Control Jumper
{CAUTION:
Be sure to use only the correct trailer brake
harness, the one intended for use on your
vehicle. If you use some other trailer brake
harness, even if it seems to t, your trailer
brakes may not work at all. You could have a
crash in which you or others could be injured.
Use only the trailer brake harness intended for
your vehicle. If it is no longer available to you,
be sure to get a proper replacement from your
dealer.This harness is included with your vehicle as part of the
heavy-duty trailer wiring package.
This harness is for an electric brake controller and
includes a trailer battery feed fuse. It should be installed
by your dealer or a qualied service center.
4-95

Service............................................................5-4
Accessories and Modications..........................5-4
California Proposition 65 Warning.....................5-4
Doing Your Own Service Work.........................5-5
Adding Equipment to the Outside of
Your Vehicle..............................................5-5
Fuel................................................................5-5
Gasoline Octane............................................5-6
Gasoline Specications....................................5-6
California Fuel...............................................5-7
Additives.......................................................5-7
Fuel E85 (85% Ethanol)..................................5-8
Fuels in Foreign Countries...............................5-9
Filling the Tank............................................5-10
Filling a Portable Fuel Container.....................5-11
Checking Things Under the Hood....................5-12
Hood Release..............................................5-13
Engine Compartment Overview.......................5-14
Engine Oil (Gasoline Engine)..........................5-20
Engine Oil Life System (Gasoline Engine)........5-23
Engine Air Cleaner/Filter (Gasoline Engines).......5-25
Automatic Transmission Fluid
(Except Allison Transmission
®) ....................5-28Automatic Transmission Fluid
(Allison Transmission
®) ...............................5-30
Manual Transmission Fluid.............................5-33
Hydraulic Clutch...........................................5-34
Engine Coolant.............................................5-35
Coolant Surge Tank Pressure Cap..................5-37
Engine Overheating.......................................5-37
Overheated Engine Protection Operating Mode
(V8 Engines Only)......................................5-39
Cooling System............................................5-40
Engine Fan Noise.........................................5-45
Power Steering Fluid.....................................5-45
Windshield Washer Fluid................................5-46
Brakes........................................................5-47
Battery........................................................5-51
Jump Starting...............................................5-52
Rear Axle.......................................................5-58
Four-Wheel Drive............................................5-59
Front Axle......................................................5-60
Noise Control System.....................................5-62
Tampering with Noise Control System
Prohibited.................................................5-62
Section 5 Service and Appearance Care
5-1

Bulb Replacement..........................................5-63
Halogen Bulbs..............................................5-63
Headlamps..................................................5-63
Front Turn Signal, Sidemarker and
Daytime Running Lamps.............................5-64
Roof Marker Lamps......................................5-66
Center High-Mounted Stoplamp (CHMSL)
and Cargo Lamp........................................5-67
Pickup Box Identication and Fender
Marker Lamps...........................................5-68
Taillamps, Turn Signal, Stoplamps and
Back-up Lamps.........................................5-68
Replacement Bulbs.......................................5-70
Windshield Wiper Blade Replacement..............5-71
Tires..............................................................5-72
Tire Sidewall Labeling...................................5-73
Tire Terminology and Denitions.....................5-76
Ination - Tire Pressure.................................5-79
Dual Tire Operation.......................................5-80
Tire Inspection and Rotation...........................5-81
When It Is Time for New Tires.......................5-83
Buying New Tires.........................................5-84
Different Size Tires and Wheels......................5-85Uniform Tire Quality Grading..........................5-86
Wheel Alignment and Tire Balance..................5-87
Wheel Replacement......................................5-87
Tire Chains..................................................5-89
If a Tire Goes Flat........................................5-90
Changing a Flat Tire.....................................5-91
Removing the Spare Tire and Tools................5-92
Removing the Flat Tire and Installing the
Spare Tire................................................5-96
Secondary Latch System..............................5-105
Storing a Flat or Spare Tire and Tools...........5-108
Spare Tire.................................................5-112
Appearance Care..........................................5-113
Cleaning the Inside of Your Vehicle...............5-113
Fabric/Carpet..............................................5-114
Leather......................................................5-115
Instrument Panel, Vinyl, and
Other Plastic Surfaces..............................5-115
Care of Safety Belts....................................5-116
Weatherstrips.............................................5-116
Washing Your Vehicle..................................5-116
Cleaning Exterior Lamps/Lenses....................5-117
Finish Care................................................5-117
Section 5 Service and Appearance Care
5-2

Windshield and Wiper Blades.......................5-118
Aluminum or Chrome-Plated Wheels..............5-118
Tires.........................................................5-119
Sheet Metal Damage...................................5-119
Finish Damage...........................................5-120
Underbody Maintenance...............................5-120
Chemical Paint Spotting...............................5-120
Vehicle Care/Appearance Materials................5-121
Vehicle Identication.....................................5-122
Vehicle Identication Number (VIN)................5-122
Service Parts Identication Label...................5-122Electrical System..........................................5-123
Add-On Electrical Equipment.........................5-123
Windshield Wiper Fuses...............................5-123
Power Windows and Other Power Options......5-123
Fuses and Circuit Breakers..........................5-123
Instrument Panel Fuse Block........................5-124
Center Instrument Panel Fuse Block..............5-126
Underhood Fuse Block................................5-127
Capacities and Specications........................5-133
Section 5 Service and Appearance Care
5-3