2003 GMC SIERRA DENALI octane

If the Light is Flashing
The following may prevent more serious damage to
your vehicle:
Reducing vehicle speed.
Avoiding hard accelerations.
0 Avoiding steep uphill grades.
If you are towing a trailer, reduce the amount of
cargo being hauled as soon as it is possible.
If the light stops flashing and remains on steady, see “If
the Light
Is On Steady” following.
If the light continues to flash, when it is safe to do
so,
stop the vehicle. Find a safe place to park your vehicle.
Turn the key
off, wait at least 10 seconds and restart
the engine. If the light remains on steady, see
“If
the Light Is On Steady” following. If the light is still
flashing, follow the previous steps, and drive the vehicle
to your dealer or qualified service center for service.
If the Light Is On Steady
You may be able to correct the emission system
malfunction by considering the following:
Did you recently put fuel into your vehicle?
If
so, reinstall the fuel cap, making sure to fully install
the cap. See
Fi//ing Your Tank on page 5-7. The
diagnostic system can determine
if the fuel cap has
been left
off or improperly installed. A loose or missing fuel
cap will allow fuel to evaporate into the atmosphere.
A few driving trips with the cap properly installed
should turn the light
off.
Did you just drive through a deep puddle of water?
If so, your electrical system may be wet. The condition
will usually be corrected when the electrical system
dries out. A few driving trips should turn the light
off.
Have you recently changed brands of fuel?
If
so, be sure to fuel your vehicle with quality fuel. See
Gasoline Octane on page 5-5. Poor fuel quality will
cause your engine not to run
as efficiently as designed.
You may notice this as stalling after start-up, stalling
when you put the vehicle into gear, misfiring, hesitation
on acceleration or stumbling on acceleration. (These
conditions may go away once the engine is warmed up.)
This will be detected by the system and cause the
light to turn on.
If you experience one or more of these conditions,
change the fuel brand you use. It will require at least
one full tank of the proper fuel to turn the light off.
If none of the above steps have made the light turn off,
have your dealer or qualified service center check
the vehicle. Your dealer has the proper test equipment
and diagnostic tools to
fix any mechanical or electrical
problems that may have developed.
3-39

Section 5 Service and Appearance Care
Service ............................................................ 5.3
Doing Your Own Service Work
......................... 5-4
Adding Equipment to the Outside
of Your Vehicle
........................................... 5-4
Fuel
................................................................ 5.5
Gasoline Octane
............................................ 5.5
Gasoline Specifications
.................................... 5.5
California Fuel
............................................... 5.6
Additives
....................................................... 5.6
Fuels in Foreign Countries
................. ....... 5.7
Filling Your Tank
......................................... 5-7
Filling a Portable Fuel Container
.................... 5-9
the Hood
............................................. 5.10
Hood Release
........................................ ,.5-10
Engine Compartment Overview
....................... 5.12
Checking
Things Under
Engine Oil
................................................... 5.13
Engine Air Cleaner/Filter
................................ 5.19
Engine Coolant
............................................. 5.24
Engine Overheating
....................................... 5.27
Cooling System
............................................ 5.30
Automatic
Transmission Fluid
........................ -5-21
Coolant Surge Tank Pressure Cap
.................. 5-27 Engine
Fan Noise
......................................... 5.36
Power Steering Fluid
..................................... 5.37
Windshield Washer Fluid
................................ 5-38
Brakes
........................................................ 5.39
Battery
........................................................ 5.42
Jump Starting
............................................... 5.43
All-Wheel Drive
......................... .............. 5-49
Rear Axle
....................................................... 5-50
Front Axle
...................................................... 5-51
Bulb Replacement
.......................................... 5-52
Halogen Bulbs
.............................................. 5-52
Headlamps
................................................. -5-52
Roof Marker Lamps
...................................... 5-54
Cargo Lamp
............................................. 5-56
Taillamps
..................................................... 5-58
Replacement Bulbs
....................................... 5-59
Front
Turn Signal, Sidemarker
and Daytime
Running Lamps
......................................... 5-53
Center High-Mounted Stoplamp (CHMSL) and
Pickup
Box Identification and Fender Marker
Lamps
..................................................... 5-58
Windshield Wiper Blade Replacement
.............. 5-60
5-
1

Fuel Gasoline Specifications
Use of the recommended fuel is an important part of the
proper maintenance of your vehicle.
Gasoline Octane
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. It
is recommended that gasoline meet specifications
which were developed by the American Automobile
Manufacturers Association and endorsed by the
Canadian Vehicle Manufacturers Association for better
vehicle performance and engine protection. Gasoline
meeting these specifications could provide improved
driveability and emission control system performance
compared to other gasoline.
In Canada,
look for the
“Auto Makers’ Choice” label
on the pump.
I I
Canada Only
5-5

California Fuel
If your vehicle is certified to meet California Emission
Standards (see the underhood emission control label),
it is designed to operate on fuels that meet California
specifications. If this fuel is not available
in states
adopting California emissions standards, your vehicle
will operate satisfactorily on fuels meeting federal
specifications, but emission control system performance
may be affected. The malfunction indicator lamp may
turn on (see
Malfunction lndicator Lamp on page 3-38 )
and your vehicle may fail a smog-check test. If this
occurs, return
to your authorized GM dealer for
diagnosis. If it is determined that the condition is caused
by the type of fuel used, repairs may not be covered
by your warranty.
Additives
To provide cleaner air, all gasolines in the United States
are now required to contain additives that will help
prevent engine and fuel system deposits from forming,
allowing your emission control system to work properly.
You should not have
to add anything to your fuel. Gasolines containing
oxygenates, such as ethers and
ethanol, and reformulated gasolines may be available in
your area to contribute
to clean air. General Motors
recommends that you use these gasolines, particularly
if
they comply with the specifications described earlier.
Notice: Your vehicle was not designed for fuel
that contains methanol. Don’t use fuel containing
methanol.
It can corrode metal parts in your
fuel system and also damage the plastic and rubber
parts. That damage wouldn’t be covered under
your warranty.
Some gasolines that are not reformulated for low
emissions may contain an octane-enhancing additive
called methylcyclopentadienyl manganese tricarbonyl
(MMT); ask the attendant where you buy gasoline
whether the fuel contains MMT. General Motors does
not recommend the use of such gasolines. Fuels
containing MMT can reduce the life of spark plugs and
the performance of the emission control system may
be affected. The malfunction indicator lamp may turn on.
If this occurs, return to your authorized GM dealer
for service.
5-6

Part A: Scheduled Maintenance
Services
This part contains engine oil and chassis lubrication scheduled maintenance which explains the engine oil life
system and how it indicates when to change the
engine oil and filter. Lubricate chassis components with
each oil change.
Also, listed are scheduled maintenance
services which are to be performed at the mileage
intervals specified.
Using Your Maintenance Schedule
We at General Motors want to help you keep your
vehicle in good condition. But we don’t know exactly how
you’ll drive it. You may drive very short distances only
a few times a week. Or you may drive long distances in
very hot, dusty weather. You may use your vehicle in
making deliveries. Or yo may drive
it to work, to
do errands or in many other ways.
Because
of all the different ways people use their
vehicles, maintenance needs vary. You may need more
frequent checks and replacements.
So please read
the following and note how you drive.
If you have any
questions on how to keep your vehicle in good condition,
see your dealer. This part tells
you the maintenance services you should
have done and when you should schedule them.
When you go to your dealer for your service needs,
you’ll know that GM-trained and supported service
people will perform the work using genuine
GM parts.
The proper fluids and lubricants
so use are listed in Part
D. Make sure whoever services your vehicle uses
these.
All parts should be replaced and all necessary
repairs done before you or anyone else drives the
vehicle.
This schedule is for vehicles that:
carry passengers and cargo within recommended
limits. You will find these limits on your vehicle’s
Certification/Tire label. See
Loading Your Vehicle on
page 4-45.
are driven on reasonable road surfaces within legal
driving limits.
are driven off-road in the recommended manner.
See
Operating Your All- Wheel-Drive Vehicle Off
Paved Roads on page 4- 16.
use the recommended fuel. See Gasoline Octane
on page 5-5.
6-4

Fluid Automatic Transmission
................................ 5-21
Power Steering
........................................... 5-37
Windshield Washer
...................................... 5-38
FM Stereo
..................................................... 3-82
Fog Lamps
.................................................... 3-14
Folding the Rear Seat
....................................... 1-7
Following Distance
.......................................... 4-57
Footnotes
........................................................ 6-5
Front Axle
...................................................... 5-51
Front Reading Lamps
...................................... 3-15
Fuel
............................................................... 5-5
Additives ...................................................... 5-6
California Fuel
.............................................. 5-6
Filling a Portable Fuel Container
..................... 5-9
Filling Your Tank
........................................... 5-7
Fuels in Foreign Countries .............................. 5-7
Gage ......................................................... 3-42
Gasoline Octane
........................................... 5-5
Gasoline Specifications .................................. 5-5
Low Warning Light ....................................... 3-42
System Inspection
....................................... 6-14
Fuel Information Button
.................................... 3-46
FUEL LEVEL LOW
......................................... 3-58
Fuses Fuses and Circuit Breakers
........................... 5-95
Windshield Wiper ......................................... 5-95
G
Gage
Engine Coolant Temperature
......................... 3-36
Fuel
.......................................................... 3-42
Oil Pressure
........................................... 3-40
Speedometer
.......................................... 3-26
Tachometer
................................................. 3-26
Transmission Temperature
............................. 3-36
Voltmeter Gage
........................................... 3-33
Garage Door Opener
....................................... 2-35
Gasoline
Octane
.................................................... 5-5
Specifications
............................................... 5-5
Glass Surfaces ............................................... 5-88
Glove Box
..................................................... 2-39
GM Mobility Program for Persons with
Disabilities
.................................................... 7-5
Gate
Operator and Canadian Programming
........ 2-37
Hazard Warning Flashers
............................... 3-3
Head Restraints
............................................... 1-6
Headlamp High/Low Beam Changer
.................... 3-6
Headlamps
.................................................... 5-52
Bulb Replacement
....................................... 5-52
Front Turn Signal, Sidemarker and Daytime
Running Lamps
........................................ 5-53