
Driving with a Trailer
{WARNING:
When towing a trailer, exhaust gases may collect
at the rear of the vehicle and enter if the liftgate,
trunk/hatch, or rear-most window is open.
Engine exhaust contains carbon monoxide (CO)
which cannot be seen or smelled. It can cause
unconsciousness and even death.
To maximize safety when towing a trailer:
•Have the exhaust system inspected for leaks
and make necessary repairs before starting
a trip.
•Never drive with the liftgate, trunk/hatch, or
rear-most window open.
•Fully open the air outlets on or under the
instrument panel.
•Adjust the Climate Control system to a setting
that brings in only outside air and set the fan
speed to the highest setting. See Climate
Control System in the Index.
For more information about carbon monoxide, see
Engine Exhaust on page 3-34.Towing a trailer requires a certain amount of experience.
Get to know the rig before setting out for the open
road. Get acquainted with the feel of handling and
braking with the added weight of the trailer. And always
keep in mind that the vehicle you are driving is now
longer and not as responsive as the vehicle is by itself.
Before starting, check all trailer hitch parts and
attachments, safety chains, electrical connectors, lamps,
tires and mirror adjustments. If the trailer has electric
brakes, start the vehicle and trailer moving and
then apply the trailer brake controller by hand to be sure
the brakes are working. This checks the electrical
connection at the same time.
During the trip, check occasionally to be sure that the
load is secure, and that the lamps and any trailer brakes
are still working.
While towing a trailer or when exposed to long periods
of sunshine, the floor of the truck bed may become
very warm. Avoid putting items in the truck bed
that might be affected by high ambient temperatures.
5-56

Driving On Grades
Reduce speed and shift to a lower gearbeforestarting
down a long or steep downgrade. If the transmission is
not shifted down, the brakes might have to be used so
much that they would get hot and no longer work well.
Vehicles with automatic transmissions can tow in
D (Drive), but you may want to shift to a lower gear
selection if the transmission shifts too often (e.g., under
heavy loads and/or hilly conditions). If the vehicle has
a manual transmission it is better not to use the
highest gear.
When towing at high altitude on steep uphill grades,
consider the following: Engine coolant will boil at a lower
temperature than at normal altitudes. If the engine is
turned off immediately after towing at high altitude on
steep uphill grades, the vehicle may show signs similar to
engine overheating. To avoid this, let the engine run whileparked, preferably on level ground, with an automatic
transmission in P (Park) or a manual transmission in
N (Neutral) with the parking brake applied, for a
few minutes before turning the engine off. If the overheat
warning comes on, seeEngine Overheating on page 6-35.
Parking on Hills
{WARNING:
Parking the vehicle on a hill with the trailer
attached can be dangerous. If something goes
wrong, the rig could start to move. People can be
injured, and both the vehicle and the trailer can be
damaged. When possible, always park the rig on a
flat surface.
5-58

Service............................................................6-3
Accessories and Modifications..........................6-3
California Proposition 65 Warning.....................6-4
California Perchlorate Materials Requirements.....6-4
Doing Your Own Service Work.........................6-4
Adding Equipment to the Outside of the
Vehicle......................................................6-5
Fuel................................................................6-5
Gasoline Octane............................................6-5
Gasoline Specifications....................................6-6
California Fuel...............................................6-6
Additives.......................................................6-6
Fuels in Foreign Countries...............................6-7
Filling the Tank..............................................6-8
Filling a Portable Fuel Container.....................6-10
Checking Things Under the Hood....................6-10
Hood Release..............................................6-11
Engine Compartment Overview.......................6-12
Engine Oil...................................................6-15
Engine Oil Life System..................................6-18
Engine Air Cleaner/Filter................................6-20
Automatic Transmission Fluid.........................6-21
Manual Transmission Fluid.............................6-25
Hydraulic Clutch...........................................6-26
Cooling System............................................6-27Engine Coolant.............................................6-29
Engine Overheating.......................................6-35
Engine Fan Noise.........................................6-36
Power Steering Fluid.....................................6-37
Windshield Washer Fluid................................6-38
Brakes........................................................6-39
Battery........................................................6-42
Jump Starting...............................................6-43
Rear Axle.......................................................6-47
Four-Wheel Drive
............................................6-48
Front Axle......................................................6-49
Headlamp Aiming...........................................6-50
Bulb Replacement..........................................6-50
Halogen Bulbs..............................................6-50
Headlamps..................................................6-51
Front Turn Signal, Parking and Daytime
Running Lamps (DRL)................................6-52
Center High-Mounted Stoplamp (CHMSL).........6-52
Taillamps, Turn Signal, Stoplamps and
Back-up Lamps.........................................6-53
License Plate Lamp......................................6-54
Replacement Bulbs.......................................6-54
Windshield Wiper Blade Replacement..............6-55
Section 6 Service and Appearance Care
6-1

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, many fluids,
and some component wear by-products contain and/or
emit these chemicals.
California Perchlorate Materials
Requirements
Certain types of automotive applications, such as
airbag initiators, seat belt pretensioners, and lithium
batteries contained in remote keyless transmitters,
may contain perchlorate materials. Special handling
may be necessary. For additional information, see
www.dtsc.ca.gov/hazardouswaste/perchlorate.
Doing Your Own Service Work
{WARNING:
You can be injured and the 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 attempting any vehicle
maintenance task.
•Be sure to use the proper nuts, bolts, and
other fasteners. English and metric fasteners
can be easily confused. If the wrong fasteners
are used, parts can later break or fall off.
You could be hurt.
If doing some of your own service work, use the proper
service manual. It tells you much more about how to
service the vehicle than this manual can. To order
the proper service manual, seeService Publications
Ordering Information on page 8-15.
6-4

Filling the Tank
{WARNING:
Fuel vapor burns violently and a fuel fire can
cause bad injuries. To help avoid injuries to you
and others, read and follow all the instructions on
the fuel pump island. Turn off the engine when
refueling. Do not smoke near fuel or when
refueling the vehicle. Do not use cellular phones.
Keep sparks, flames, and smoking materials away
from fuel. Do not leave the fuel pump unattended
when refueling the vehicle. This is against the law
in some places. Do not re-enter the vehicle while
pumping fuel. Keep children away from the fuel
pump; never let children pump fuel.The tethered fuel cap is located behind a hinged fuel
door on the driver side of the vehicle.
To remove the fuel cap, turn it slowly counterclockwise.
While refueling, hang the tethered fuel cap from the
hook on the fuel door.
6-8

{WARNING:
Fuel can spray out on you if you open the fuel cap
too quickly. If you spill fuel and then something
ignites it, you could be badly burned. This spray
can happen if the tank is nearly full, and is more
likely in hot weather. Open the fuel cap slowly and
wait for any hiss noise to stop. Then unscrew the
cap all the way.
Be careful not to spill fuel. Do not top off or overfill the
tank and wait a few seconds after you have finished
pumping before removing the nozzle. Clean fuel from
painted surfaces as soon as possible. SeeWashing
Your Vehicle on page 6-106.
When replacing the fuel cap, turn it clockwise until it
clicks. Make sure the cap is fully installed. The diagnostic
system can determine if the fuel cap has been left off or
improperly installed. This would allow fuel to evaporate
into the atmosphere. If the fuel cap is not properlyinstalled, the FUEL CAP message appears on the Driver
Information Center (DIC) and the check engine light will
be lit on the instrument panel cluster. SeeDIC Warnings
and Messages on page 4-37andMalfunction Indicator
Lamp on page 4-28for more information.
{WARNING:
If a fire starts while you are refueling, do not
remove the nozzle. Shut off the flow of fuel by
shutting off the pump or by notifying the station
attendant. Leave the area immediately.
Notice:If you need a new fuel cap, be sure to get
the right type. Your dealer/retailer can get one
for you. If you get the wrong type, it may not t
properly. This may cause the malfunction indicator
lamp to light and may damage the fuel tank and
emissions system. SeeMalfunction Indicator Lamp
on page 4-28.
6-9

Filling a Portable Fuel Container
{WARNING:
Never fill a portable fuel container while it is in
the vehicle. Static electricity discharge from the
container can ignite the fuel vapor. You can be
badly burned and the vehicle damaged if this
occurs. To help avoid injury to you and others:
•Dispense fuel only into approved containers.
•Do not fill a container while it is inside a
vehicle, in a vehicle’s trunk, pickup bed,
or on any surface other than the ground.
•Bring the fill nozzle in contact with the inside
of the fill opening before operating the nozzle.
Contact should be maintained until the filling
is complete.
•Do not smoke while pumping fuel.
•Do not use a cellular phone while
pumping fuel.
Checking Things Under
the Hood
{WARNING:
Things that burn can get on hot engine parts and
start a fire. These include liquids like fuel, oil,
coolant, brake fluid, windshield washer and other
fluids, 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.
6-10

Engine Oil Additives / Engine Oil
Flushes
Do not add anything to the oil. The recommended
oils with the starburst symbol that meet GM Standard
GM6094M are all that is needed for good performance
and engine protection.
Engine oil system flushes are not recommended and
could cause engine damage not covered by the vehicle
warranty.
Engine Oil Life System
When to Change Engine Oil
This vehicle has a computer system that indicates when
to change the engine oil and filter. This is based on
engine revolutions and engine temperature, and not on
mileage. Based on driving conditions, the mileage at
which an oil change is indicated can vary considerably.
For the oil life system to work properly, the system
must be reset every time the oil is changed.When the system has calculated that oil life has been
diminished, it indicates that an oil change is necessary.
A CHANGE OIL message comes on. SeeDIC Warnings
and Messages on page 4-37. Change the oil as soon
as possible within the next 600 miles (1 000 km). It is
possible that, if driving under the best conditions, the
oil life system might not indicate that an oil change is
necessary for over a year. However, the engine oil and
filter must be changed at least once a year and at this
time the system must be reset. Your dealer/retailer has
trained people who will perform this work using genuine
parts and reset the system. It is also important to check
the oil regularly and keep it at the proper level.
If the system is ever reset accidentally, the oil must be
changed at 3,000 miles (5 000 km) since the last oil
change. Remember to reset the oil life system whenever
the oil is changed.
6-18