Other Service Items........................................5-66
Fuel Filter....................................................5-66
Primary Fuel Filter and Water Separator..........5-67
Secondary Fuel Filter and Water Separator/
Heater (Caterpillar
®Diesel)..........................5-68
Automatic Ether Injection System
(Caterpillar
®Diesel)....................................5-68
Front Wheel Bearings with Oil-Filled Hubs........5-69
Air Conditioning System.................................5-70
Tires..............................................................5-70
Inflation - Tire Pressure.................................5-71
Wheel Loading.............................................5-71
Dual Tire Operation.......................................5-72
When It Is Time for New Tires.......................5-72
Wheel Alignment and Tire Balance..................5-73
Tightening the Wheel Nuts.............................5-73
Wheel Replacement......................................5-77
If a Tire Goes Flat........................................5-78
Appearance Care............................................5-79
Cleaning the Inside of Your Vehicle.................5-80
Fabric/Carpet...............................................5-81
Instrument Panel, Vinyl, and Other
Plastic Surfaces........................................5-82
Care of Safety Belts......................................5-82
Weatherstrips...............................................5-82Washing Your Vehicle...................................5-83
Cleaning Exterior Lamps/Lenses.....................5-83
Finish Care..................................................5-83
Windshield and Wiper Blades.........................5-84
Aluminum or Chrome-Plated Wheels................5-84
Tires...........................................................5-85
Sheet Metal Damage.....................................5-85
Finish Damage.............................................5-85
Underbody Maintenance................................5-85
Chemical Paint Spotting.................................5-85
Vehicle Identi cation......................................5-87
Vehicle Identification Number (VIN).................5-87
Service Statement.........................................5-87
Service Parts Identification Label.....................5-88
Electrical System............................................5-88
Add-On Electrical Equipment..........................5-88
Headlamp Wiring..........................................5-88
Windshield Wiper Fuses................................5-88
Fusible Links................................................5-89
Power Windows and Other Power Options.......5-89
Fuses and Circuit Breakers............................5-89
Instrument Panel Fuse Block..........................5-89
Underhood Fuse Block..................................5-92
Capacities and Speci cations..........................5-95
Normal Maintenance Replacement Parts.........5-100
Section 5 Service and Appearance Care
5-2
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 fluids, and
some component wear by-products contain and/or emit
these chemicals.
5-3
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 7-8.
Your vehicle has an airbag system. Before attempting
to do your own service work, seeServicing Your
Airbag-Equipped Vehicle on page 1-59.
You should keep a record with all parts receipts and list
the mileage and the date of any service work you
perform. SeePart D: Maintenance Record on page 6-34.{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.
5-4
Two Safety Cautions about
Engine Fan Breakage
{CAUTION:
Changing the Fan Drive Ratio or Engine
Governed Speed:
If you change the fan drive ratio or increase
the governed speed of the engine, you may
increase stress and the fan could eventually fail.
If the fan breaks apart while it is rotating, pieces
can cause severe injury to anyone — such as
a service technician — who is nearby. And, of
course, the pieces can severely damage the
vehicle. Do not change the fan drive ratio or
increase the governed speed of the vehicle
without getting the necessary information from
your dealer.
CAUTION: (Continued)
CAUTION: (Continued)
Winter Fronts, Grille Covers or Obstructions:
Winter Fronts, grille covers or other add-on
equipment causing obstructions in front or
behind the fan should not be used on this
vehicle. If this causes the fan to eventually
break apart while it is rotating, the pieces can
cause severe injury to anyone nearby, such as
a service technician working on the engine,
and of course the pieces can severely damage
the vehicle.
5-5
Fuel
If your vehicle has a diesel engine, seeDiesel Engine
Fuel on page 5-7.
For vehicles with gasoline engines, please read this.
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.
Gasoline Speci cations
It is recommended that gasoline meet specifications
which were developed by automobile manufacturers
around the world and contained in the World-Wide Fuel
Charter which is available from the Alliance of Automobile
Manufacturers at www.autoalliance.org/fuel_charter.htm.
Gasoline meeting these specifications could provide
improved driveability and emission control system
performance compared to other gasoline.
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.
In most cases, you should not have to add anything to
your fuel. However, some gasolines contain only the
minimum amount of additive required to meet
U.S. Environmental Protection Agency regulations.
General Motors recommends that you buy gasolines that
are advertised to help keep fuel injectors and intake
valves clean. If your vehicle experiences problems due to
dirty injectors or valves, try a different brand of gasoline.
Also, your GM dealer has additives that will help correct
and prevent most deposit-related problems.
5-6
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. Do not use fuel containing
methanol. It can corrode metal parts in your fuel
system and also damage the plastic and rubber
parts. That damage would not 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.Diesel Engine Fuel
For the Caterpillar®diesel, see the Caterpillar®
Operation & Maintenance Manual for information
concerning fuel usage.
Notice:Diesel fuel or fuel additives not
recommended in this manual could damage your
fuel system and engine. Your warranty would
not cover this damage. And:
Diesel fuel that has been mixed with engine oil
or automatic transmission uid could damage
your engine and emission controls.
Aftermarket diesel fuel additives are not tested
by General Motors. Some additives, particularly
those which contain alcohol or water emulsi ers,
may damage your fuel system. If you believe that
unique circumstances call for a fuel additive to
be used, consult your dealer for advice.
If you ever run out of diesel fuel, it can be difficult
to restart your engine. To avoid all this, never let
your tank get empty.
If gasoline is ever accidentally added to the fuel
tank, to avoid severe engine damage, do not run the
engine until the fuel tank can be drained.
If you run out of fuel,Running Out of Fuel on page 5-15
tells you how to restart your engine.
5-7
Very Cold Weather Operation
Follow the instructions listed previously under the
heading “What Fuel to Use.”
Notice:Never use home heating oil or gasoline in
your diesel engine. They can cause engine
damage.
In cold weather, your fuel filter may become clogged
(waxed). To unclog it, move the vehicle to a warm
garage area and warm the filter to between 32°F and
50°F (0°C to 10°C). You will not need to replace it.
Additional information on the fuel filter follows.
Water in Fuel
{CAUTION:
Diesel fuel containing water is still ammable.
You could be burned. If you ever try to drain
water from your fuel, keep sparks, ames and
smoking materials away from the mixture.Notice:If there is water in your diesel fuel and the
weather is warm or humid, fungus and bacteria
can grow in the fuel. They can damage your
fuel system. A diesel fuel biocide can be used to
sterilize your fuel system. However, your fuel system
may still need to be cleaned. Your dealer can
advise you of the appropriate solution.
If your fuel tank needs to be purged to remove
water, see your dealer or a quali ed technician.
Improper purging can damage your fuel system.
Sometimes, water can be pumped into your fuel
tank along with your diesel fuel. This can happen if a
service station does not regularly inspect and clean
its fuel tanks, or if it gets contaminated fuel from
its suppliers.
If this happens, the
water-in-fuel light, if
equipped, will come on in
the instrument panel. If it
does, the water must be
drained. Your dealer can
show you how to do this.
If the light comes on, use this chart to determine what
action to take.
5-10
•SAE 15W-40
As shown in the viscosity chart, SAE 15W-40 is
best for your vehicle. However, you can use
SAE 10W-30 at temperatures above 0°F (−18°C).
When it is very cold, below 0°F (−18°C), you should
use SAE 5W-40 to improve cold starting.
These numbers on the oil container show its
viscosity, or thickness. Do not use other viscosity
oils such as SAE 10W-40 or SAE 20W-50.
This doughnut-shaped
logo (symbol) is used on
most oil containers to
help you select the correct
oil. It means that the oil
has been certified by
the American Petroleum
Institute.
You should look for this on the oil container, and use
onlythose oils that display this logo.
GM Goodwrench
®oil of the recommended viscosity
grades meets all the requirements for your vehicle.
Engine Oil Additives
Do not add anything to your oil. The recommended oils
with the API service symbol are all you will need for
good performance and engine protection.
When to Change Engine Oil (Vehicles
Without the Engine Oil Life System)
If you have the 6.6L V8 (LLY) Engine: Change engine
oil and filter every 15,000 miles (24 000 km), or
every 12 months, or every 750 hours of engine
operation, whichever occurs first. If you have the
7.8L V6 (LG4) Engine: Change engine oil and filter
every 12,000 miles (20 000 km), or every 12 months,
or every 600 hours of engine operation, whichever
occurs first. SeeScheduled Maintenance on page 6-5.
5-25