
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, and
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. See the Maintenance Schedule for more
on this. Things that are especially important in trailer
operation are automatic transmission uid (don’t over ll),
engine oil, axle lubricant, belts, 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
Heavy-Duty Trailer Wiring Package
Your vehicle is equipped with the eight-wire trailer
towing harness. This harness with a seven-pin universal
heavy-duty trailer connector is attached to a bracket
on the hitch platform.
The Center High-Mounted Stoplamp (CHMSL) wire is tied
next to the trailer wiring harness for use with a trailer.
4-74

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 Speci cations....................................5-5
California Fuel...............................................5-5
Additives.......................................................5-6
Fuel E-85 (85% Ethanol).................................5-6
Fuels in Foreign Countries...............................5-7
Filling the Tank..............................................5-8
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...................................................5-15
Engine Oil Life System..................................5-18
Engine Air Cleaner/Filter................................5-20
Automatic Transmission Fluid.........................5-22
Engine Coolant.............................................5-25
Coolant Surge Tank Pressure Cap..................5-28
Engine Overheating.......................................5-28
Overheated Engine Protection Operating Mode . . .5-30Cooling System............................................5-30
Engine Fan Noise.........................................5-35
Power Steering Fluid.....................................5-36
Windshield Washer Fluid................................5-36
Brakes........................................................5-38
Battery........................................................5-41
Jump Starting...............................................5-42
Rear Axle.......................................................5-47
Four-Wheel Drive............................................5-48
Front Axle......................................................5-49
Bulb Replacement..........................................5-50
Halogen Bulbs..............................................5-50
Headlamps..................................................5-50
Front Turn Signal, Sidemarker and Parking
Lamps.....................................................5-53
Front Turn Signal, Sidemarker and Daytime
Running Lamps.........................................5-54
Daytime Running Lamps (DRL).......................5-56
Taillamps, Turn Signal, Stoplamps and
Back-up Lamps.........................................5-57
Replacement Bulbs.......................................5-58
Windshield Wiper Blade Replacement..............5-58
Section 5 Service and Appearance Care
5-1

to use it. The ethanol in E-85 is a “renewable” fuel,
meaning it is made from renewable sources such as corn
and other crops.
Many service stations will not have an 85% ethanol
fuel (E-85) pump available. The U. S. Department
of Energy has an alternative fuels website
(http://www.afdc.doe.gov/refueling_mapsite.shtml) that
can help you nd E-85 fuel. Those stations that do have
E-85 should have a label indicating ethanol content.
Do not use the fuel if the ethanol content isgreaterthan
85%. Your vehicle may not operate properly if the
ethanol content is greater than 85%.
At a minimum, E-85 should meet ASTM Speci cation
D 5798.
To ensure quick starts in the wintertime, the E-85 fuel
must be formulated properly for your climate according to
ASTM speci cation D 5798. If you have trouble starting
on E-85, it may be because your E-85 fuel is not properly
formulated for your climate. If this happens, switching to
gasoline or adding gasoline to your fuel tank may improve
starting. Your vehicle is designed to accommodate a
mixture of gasoline and E-85 fuel. For good starting and
heater efficiency below 32°F (0°C), the fuel mix in the fuel
tank should contain no more than 70% ethanol.
E-85 has less energy per gallon than gasoline, so
you will need to re ll your fuel tank more often when
using E-85 than when you are using gasoline. Regularunleaded gasoline is recommended when pulling a
trailer. For payload capacity with ethanol fuel, see
Loading Your Vehicle on page 4-47.
Notice:Some additives are not compatible with
E-85 fuel and may harm your fuel system. Damage
caused by additives would not be covered by
your new vehicle warranty. Do not use additives
with E-85 fuel.
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.
Fuels in Foreign Countries
If you plan on driving in another country outside the
United States or Canada, the proper fuel may be hard
to nd. Never use leaded gasoline or any other fuel
not recommended in the previous text on fuel. Costly
repairs caused by use of improper fuel would not
be covered by your warranty.
To check the fuel availability, ask an auto club, or
contact a major oil company that does business in the
country where you will be driving.
5-7

Checking Things Under
the Hood
{CAUTION:
An electric fan under the hood can start up
and injure you even when the engine is not
running. Keep hands, clothing and tools away
from any underhood electric fan.
{CAUTION:
Things that burn can get on hot engine parts
and start a re. These include liquids like fuel,
oil, coolant, brake uid, windshield washer and
other uids, and plastic or rubber. You or
others could be burned. Be careful not to drop
or spill things that will burn onto a hot engine.
Hood Release
To open the hood, do the following:
1. Pull the handle with this
symbol on it. It is
located inside the
vehicle to the lower left
of the steering column.
5-10

A. Engine Air Cleaner/Filter. SeeEngine Air
Cleaner/Filter on page 5-20.
B. Coolant Surge Tank and Pressure Cap. SeeCooling
System on page 5-30andCoolant Surge Tank
Pressure Cap on page 5-28.
C. Air Filter Restriction Indicator (If Equipped). See
Engine Air Cleaner/Filter on page 5-20.
D. Engine Oil Fill Cap. See “When to Add Engine Oil”
underEngine Oil on page 5-15.
E. Engine Oil Dipstick. See “Checking Engine Oil”
underEngine Oil on page 5-15.
F. Automatic Transmission Fluid Dipstick. See
“Checking the Fluid Level” underAutomatic
Transmission Fluid on page 5-22.
G. Engine Cooling Fan. SeeCooling System on
page 5-30.H. Remote Negative (−) Terminal (GND). SeeJump
Starting on page 5-42.
I. Power Steering Fluid Reservoir (Out of View). See
Power Steering Fluid on page 5-36.
J. Remote Positive (+) Terminal. SeeJump Starting on
page 5-42.
K. Brake Fluid Reservoir. See “Brake Fluid” under
Brakes on page 5-38.
L. Underhood Fuse Block. SeeUnderhood Fuse Block
on page 5-107.
M. Battery. SeeBattery on page 5-41.
N. Windshield Washer Fluid Reservoir. See “Adding
Washer Fluid” underWindshield Washer Fluid
on page 5-36.
5-13

A. Engine Air Cleaner/Filter. SeeEngine Air
Cleaner/Filter on page 5-20.
B. Coolant Surge Tank and Pressure Cap. SeeCooling
System on page 5-30andCoolant Surge Tank
Pressure Cap on page 5-28.
C. Air Filter Restriction Indicator (If Equipped). See
Engine Air Cleaner/Filter on page 5-20.
D. Engine Oil Dipstick. See “Checking Engine Oil”
underEngine Oil on page 5-15.
E. Automatic Transmission Fluid Dipstick. See
“Checking the Fluid Level” underAutomatic
Transmission Fluid on page 5-22.
F. Engine Oil Fill Cap. See “When to Add Engine Oil”
underEngine Oil on page 5-15.
G. Engine Cooling Fan. SeeCooling System on
page 5-30.
H. Remote Negative (−) Terminal (GND). SeeJump
Starting on page 5-42.
I. Remote Positive (+) Terminal. SeeJump Starting on
page 5-42.
J. Power Steering Fluid Reservoir. SeePower Steering
Fluid on page 5-36.
K. Brake Fluid Reservoir. See “Brake Fluid” under
Brakes on page 5-38.
L. Underhood Fuse Block. SeeUnderhood Fuse Block
on page 5-107.M. Battery. SeeBattery on page 5-41.
N. Windshield Washer Fluid Reservoir. See “Adding
Washer Fluid” underWindshield Washer Fluid
on page 5-36.
Engine Oil
If the CHECK OIL LEVEL message appears on the
instrument cluster, it means you need to check
your engine oil level right away.
For more information, see CHECK OIL LEVEL under
DIC Warnings and Messages on page 3-49.
You should check your engine oil level regularly; this is
an added reminder.
Checking Engine Oil
It is a good idea to check your engine oil every time you
get fuel. In order to get an accurate reading, the oil
must be warm and the vehicle must be on level ground.
The engine oil dipstick handle is a yellow loop. See
Engine Compartment Overview on page 5-12for
the location of the engine oil dipstick.
1. Turn off the engine and give the oil several minutes
to drain back into the oil pan. If you do not do this,
the oil dipstick might not show the actual level.
5-15

2. Pull out the dipstick and clean it with a paper towel
or cloth, then push it back in all the way. Remove it
again, keeping the tip down, and check the level.
When to Add Engine Oil
If the oil is below the cross-hatched area at the tip of
the dipstick, you will need to add at least one quart/liter
of oil. But you must use the right kind. This section
explains what kind of oil to use. For engine oil crankcase
capacity, seeCapacities and Speci cations on
page 5-112.Notice:Do not add too much oil. If the engine has
so much oil that the oil level gets above the
cross-hatched area that shows the proper operating
range, the engine could be damaged.
SeeEngine Compartment
Overview on page 5-12for
the location of the
engine oil ll cap.
Be sure to add enough oil to put the level somewhere in
the proper operating range. Push the dipstick all the
way back in when you are through. 8.1L Engine
All Except 8.1L Engine
5-16

If you are in an area of extreme cold, where the
temperature falls below−20°F (−29°C), it is
recommended that you use either an SAE 5W-30
synthetic oil or an SAE 0W-30 oil. Both will provide
easier cold starting and better protection for your engine
at extremely low temperatures.
Engine Oil Additives
Do not add anything to your oil. The recommended oils
with the starburst symbol that meet GM Standard
GM6094M are all you will need for good performance
and engine protection.
Engine Oil Life System
When to Change Engine Oil
Your vehicle has a computer system that lets you know
when to change the engine oil and lter. This is based on
engine revolutions and engine temperature, and not on
mileage. Based on driving conditions, the mileage at
which an oil change will be indicated can vary
considerably. For the oil life system to work properly, you
must reset the system every time the oil is changed.When the system has calculated that oil life has been
diminished, it will indicate that an oil change is
necessary. A CHANGE ENGINE OIL message will
come on. Change your oil as soon as possible within
the next 600 miles (1 000 km). It is possible that, if you
are driving under the best conditions, the oil life
system may not indicate that an oil change is necessary
for over a year. However, your engine oil and lter
must be changed at least once a year and at this time
the system must be reset. Your dealer has GM-trained
service people who will perform this work using
genuine GM parts and reset the system. It is also
important to check your oil regularly and keep it at the
proper level.
If the system is ever reset accidentally, you must
change your oil at 3,000 miles (5 000 km) since your
last oil change. Remember to reset the oil life system
whenever the oil is changed.
5-18