2005 GMC SIERRA Owner's Manual

Preset Mode:PTO speed control mode is used for
stationary applications. (PTO will remain engaged while
mobile in the preset mode, however PTO set and
resume speed controls will be inoperative.) This mode
provides a default standby speed of 800 or 850 rpm
(depending on the engine/transmission combination) and
two default PTO control speeds which follow:
1. PTO Set Speed of 1,250 rpm, or
2. PTO Resume Speed of 1,700 rpm.
Please note that the standby speed (800/850 rpm) is
not to be used as a PTO control speed. Vehicles
not equipped with cruise control will not have the resume
speed capability.
To use PTO speed control in variable mode (while
mobile) do the following:
1. Engage the PTO.
2. Vehicle speed must be greater than 5 mph.
3. Make sure your foot is off the brake pedal (and off
the clutch for vehicles equipped with a manual
transmission).
4. Select the desired engine speed by using the foot
pedal, and select SET on the PTO switch or the
cruise control.To use PTO speed control in variable mode (while
stationary) do the following:
1. Engage the PTO.
2. Vehicle speed must be less than 5 mph.
3. Make sure your foot is off the brake pedal (and off
the clutch for vehicles equipped with a manual
transmission).
4. Select the desired engine speed by using the foot
pedal, and select SET on the PTO switch or the
cruise control.
Variable Mode:PTO speed control mode can be used
for both stationary and mobile applications. This
mode allows PTO to be controlled in a fashion similar to
how cruise control sets vehicle speed. The operator
can set to an rpm (between 800 and 2,200) with
the cruise control feature or with the SET position on
the PTO switch. The operator is then able to increase
rpm in increments of 100, or “tap up” with the resume
position on the cruise control. The operator can
also decrease rpm in increments of 100 with the SET
switch on the PTO or the cruise control.
Vehicles not equipped with cruise control will not have
the “tap up” capability.
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All engine speed values listed above are factory preset
values. With the exception of the TCC lockup speed
(1,100 rpm) and the “tap” increment (100 rpm), all
of these values are programmable and can be adjusted
by your dealer or body uptter. If the PTO software
settings do not match the settings shown here, then they
may have already been altered in order to satisfy the
requirements of the installed PTO system and body
equipment.
When the PTO switch is turned on, the engine is limited
to 2,200 rpms. If there are no accessories installed
on the vehicle, make sure the PTO switch is turned off.Step-Bumper Pad
Your vehicle has a rear step bumper with a rear step
pad at the center of the bumper.
If you will be using the
bumper to tow a trailer,
and your step-bumper has
three cutout circles, you
must push out the
center cutout circle to
install the trailer ball.
If your step-bumper has only one cutout circle, you will
have to cut out the circle, then remove it to install
the trailer ball.
4-100

Service............................................................5-4
Doing Your Own Service Work.........................5-5
Adding Equipment to the Outside
of Your Vehicle...........................................5-6
Fuel................................................................5-6
Gasoline Octane............................................5-6
Gasoline Specications....................................5-7
California Fuel...............................................5-7
Additives.......................................................5-7
Fuel E-85 (85% Ethanol).................................5-8
Fuels in Foreign Countries...............................5-9
Filling Your Tank..........................................5-10
Filling a Portable Fuel Container.....................5-12
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................................5-25
Automatic Transmission Fluid
(Except Allison Transmission
®) ....................5-27
Automatic Transmission Fluid
(Allison Transmission
®) ...............................5-30
Manual Transmission Fluid.............................5-33
Hydraulic Clutch...........................................5-34Engine 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.....................................5-46
Windshield Washer Fluid................................5-48
Brakes........................................................5-49
Battery........................................................5-52
Jump Starting...............................................5-53
Rear Axle.......................................................5-58
Four-Wheel Drive............................................5-58
Front Axle......................................................5-60
Noise Control System.....................................5-61
Tampering with Noise Control System
Prohibited.................................................5-61
Bulb Replacement..........................................5-62
Halogen Bulbs..............................................5-62
Headlamps..................................................5-63
Front Turn Signal, Sidemarker and
Daytime Running Lamps.............................5-64
Roof Marker Lamps......................................5-65
Section 5 Service and Appearance Care
5-1

Center High-Mounted Stoplamp (CHMSL)
and Cargo Lamp.......................................5-67
Pickup Box Identication and Fender
Marker Lamps...........................................5-69
Taillamps.....................................................5-69
Replacement Bulbs.......................................5-71
Windshield Wiper Blade Replacement..............5-72
Tires..............................................................5-72
Tire Sidewall Labelling...................................5-74
Tire Terminology and Denitions.....................5-77
Ination - Tire Pressure.................................5-79
Dual Tire Operation.......................................5-82
Tire Inspection and Rotation...........................5-83
When It Is Time for New Tires.......................5-85
Buying New Tires.........................................5-86
Uniform Tire Quality Grading..........................5-87
Wheel Alignment and Tire Balance..................5-88
Wheel Replacement......................................5-88
Tire Chains..................................................5-90
If a Tire Goes Flat........................................5-91
Changing a Flat Tire.....................................5-92
Removing the Spare Tire and Tools................5-93
Removing the Flat Tire and Installing
the Spare Tire..........................................5-97Secondary Latch System..............................5-105
Storing a Flat or Spare Tire and Tools...........5-109
Spare Tire.................................................5-112
Appearance Care..........................................5-112
Fabric/Carpet..............................................5-113
Vinyl.........................................................5-114
Leather......................................................5-114
Instrument Panel.........................................5-115
Interior Plastic Components..........................5-115
Glass Surfaces...........................................5-115
Care of Safety Belts....................................5-115
Weatherstrips.............................................5-115
Washing Your Vehicle..................................5-116
Cleaning Exterior Lamps/Lenses....................5-116
Finish Care................................................5-116
Windshield and Wiper Blades.......................5-117
Aluminum or Chrome-Plated Wheels..............5-117
Tires.........................................................5-118
Sheet Metal Damage...................................5-118
Finish Damage...........................................5-118
Underbody Maintenance...............................5-119
Chemical Paint Spotting...............................5-119
Vehicle Care/Appearance Materials................5-119
Section 5 Service and Appearance Care
5-2

Vehicle Identication.....................................5-120
Vehicle Identication Number (VIN)................5-120
Service Parts Identication Label...................5-121
Electrical System..........................................5-121
Add-On Electrical Equipment.........................5-121
Windshield Wiper Fuses...............................5-121
Power Windows and Other
Power Options........................................5-122Fuses and Circuit Breakers..........................5-122
Instrument Panel Fuse Block........................5-122
Center Instrument Panel Fuse Block..............5-124
Underhood Fuse Block................................5-125
Capacities and Specications........................5-130
Section 5 Service and Appearance Care
5-3

Service
Your dealer knows your vehicle best and wants you to
be happy with it. We hope you will go to your dealer
for all your service needs. You will get genuine GM parts
and GM-trained and supported service people.
We hope you will want to keep your GM vehicle all GM.
Genuine GM parts have one of these marks:
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
(including some inside the vehicle), many uids, and
some component wear by-products contain and/or emit
these chemicals.
5-4

Doing Your Own Service Work
If you want to do some of your own service work, you
will want to use the proper service manual. It tells
you much more about how to service your vehicle than
this manual can. To order the proper service manual,
seeService Publications Ordering Information on
page 7-11.
Your vehicle has an airbag system. Before attempting to
do your own service work, seeServicing Your
Airbag-Equipped Vehicle on page 1-80.
You should keep a record with all parts receipts and list
the mileage and the date of any service work you
perform. SeeMaintenance Record on page 6-18.{CAUTION:
You can be injured and your 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 you attempt any vehicle
maintenance task.
Be sure to use the proper nuts, bolts and
other fasteners. English and metric
fasteners can be easily confused. If you
use the wrong fasteners, parts can later
break or fall off. You could be hurt.
5-5

Adding Equipment to the Outside
of Your Vehicle
Things you might add to the outside of your vehicle can
affect the airow around it. This may cause wind
noise and affect windshield washer performance. Check
with your dealer before adding equipment to the
outside of your vehicle.
Fuel
If your vehicle has a diesel engine, see “Diesel Fuel
Requirements and Fuel System” in the Diesel Engine
Supplement.
For vehicles with gasoline engines, please read this.
Gasoline Octane
For all except vehicles with the 6000 V8 (VIN Code N)
engine, use regular unleaded gasoline with a posted
octane of 87 or higher. If the octane is less than 87, you
may get a heavy knocking noise when you drive. If this
occurs, use a gasoline rated at 87 octane or higher as
soon as possible. Otherwise, you might damage your
engine. A little pinging noise when you accelerate or drive
uphill is considered normal. This does not indicate a
problem exists or that a higher-octane fuel is necessary.
If you are using 87 octane or higher-octane fuel and hear
heavy knocking, your engine needs service.
If you have the 6000 V8 (VIN Code N) engine, use
premium unleaded gasoline with a posted octane of
91 or higher for best performance. You may also
use middle grade or regular unleaded gasoline rated at
87 octane or higher, but your vehicle’s acceleration
may be slightly reduced. If the octane is less than 87,
you may get a heavy knocking noise when you drive.
If this occurs, use gasoline rated at 87 octane or higher
as soon as possible. Otherwise, you might damage
your engine.
5-6