Backing Up
Hold the bottom of the steering wheel with one hand.
Then, to move the trailer to the left, move that hand to
the left. To move the trailer to the right, move your hand
to the right. Always back up slowly and, if possible,
have someone guide you.
Making Turns
Notice:Making very sharp turns while trailering
could cause the trailer to come in contact with
the vehicle. The vehicle could be damaged.
Avoid making very sharp turns while trailering.
When turning with a trailer, make wider turns than
normal. Do this so the trailer will not strike soft
shoulders, curbs, road signs, trees or other objects.
Avoid jerky or sudden maneuvers. Signal well
in advance.
If the trailer turn signal bulbs burn out, the arrows on
the instrument panel will still flash for turns. It is
important to check occasionally to be sure the trailer
bulbs are still working.
Driving On Grades
Reduce speed and shift to a lower gear beforestarting
down a long or steep downgrade. If the transmission is
not shifted down, the brakes might get hot and no
longer work well.
Vehicles can tow in D (Drive). Shift the transmission to
a lower gear if the transmission shifts too often under
heavy loads and/or hilly conditions.
The tow/haul mode may be used if the transmission
shifts too often. See Tow/Haul Mode on page 3‑39.
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
while parked, preferably on level ground, with the
automatic transmission in P (Park) for a few minutes
before turning the engine off. If the overheat warning
comes on, see Engine Overheating on page 7‑33.
6-51
Maintenance When Trailer Towing
The vehicle needs service more often when pulling a
trailer. See this manual's Maintenance Schedule or
Index for more information. Things that are especially
important in trailer operation are automatic transmission
fluid, engine oil, axle lubricant, belts, cooling system
and brake system. It is a good idea to inspect these
before and during the trip.
Check periodically to see that all hitch nuts and bolts
are tight.
Trailer Wiring Harness
Heavy-Duty Trailer Wiring Harness Package
The vehicle has a seven-pin universal heavy-duty trailer
connector attached to the rear bumper beam next to the
integrated trailer hitch.The seven-wire harness contains the following
trailer circuits:
.Yellow: Left Stop/Turn Signal
.Dark Green: Right Stop/Turn Signal
.Brown: Taillamps
.White: Ground
.Light Green: Back-up Lamps
.Red w/ Black Stripe: Battery Feed*
.Dark Blue: Trailer Brake*
*The fuses for these two circuits are installed in the
underhood electrical center, but the wires are not
connected. They should be connected by your
dealer/retailer or a qualified service center.
If charging a remote (non-vehicle) battery, press the
tow/haul mode button located at the end of the shift
lever. This will boost the vehicle system voltage and
properly charge the battery. If the trailer is too light for
tow/haul mode, turn on the headlamps as a second way
to boost the vehicle system and charge the battery.
6-53
Section 7 Service and Appearance Care
Service. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-4
Accessories and Modifications . . . . . . . . . . . . . . . . . . 7-4
California Proposition 65 Warning . . . . . . . . . . . . . . . 7-5
California Perchlorate Materials Requirements . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-5
Doing Your Own Service Work . . . . . . . . . . . . . . . . . . 7-5
Adding Equipment to the Outside of the Vehicle . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-6
Fuel . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-6
Gasoline Octane . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-7
Gasoline Specifications . . . . . . . . . . . . . . . . . . . . . . . . . 7-7
California Fuel . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-7
Additives . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-7
Fuel E85 (85% Ethanol) . . . . . . . . . . . . . . . . . . . . . . . . . 7-8
Fuels in Foreign Countries . . . . . . . . . . . . . . . . . . . . . . 7-9
Filling the Tank . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-10
Filling a Portable Fuel Container . . . . . . . . . . . . . . . 7-12
Checking Things Under the Hood . . . . . . . . . . . . . . .7-12
Hood Release . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-13
Engine Compartment Overview . . . . . . . . . . . . . . . . 7-14
Engine Oil . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-15
Engine Oil Life System . . . . . . . . . . . . . . . . . . . . . . . . 7-18
Engine Air Cleaner/Filter . . . . . . . . . . . . . . . . . . . . . . . 7-20 Automatic Transmission Fluid . . . . . . . . . . . . . . . . . . 7-22
Cooling System . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-26
Engine Coolant . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-27
Engine Overheating . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-33
Overheated Engine Protection
Operating Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-35
Engine Fan Noise . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-35
Power Steering Fluid . . . . . . . . . . . . . . . . . . . . . . . . . . 7-36
Windshield Washer Fluid . . . . . . . . . . . . . . . . . . . . . . 7-37
Brakes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-38
Battery . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-41
Jump Starting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-42
All-Wheel Drive . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-47
Rear Axle . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-48
Front Axle . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-49
Headlamp Aiming . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-50
Bulb Replacement . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-53
High Intensity Discharge (HID) Lighting . . . . . . . . 7-53
Taillamps, Turn Signal, Sidemarker, Stoplamps and Back-up Lamps . . . . . . . . . . . . . . . . . . . . . . . . . 7-53
License Plate Lamp . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-55
Replacement Bulbs . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-55
7-1
At a minimum, E85 should meet ASTM Specification
D 5798. By definition, this means that fuel labeled E85
will have an ethanol content between 70% and 85%.
Filling the fuel tank with fuel mixtures that do not meet
ASTM specifications can affect driveability and could
cause the malfunction indicator lamp to come on.
To ensure quick starts in the wintertime, the E85 fuel
must be formulated properly for your climate according
to ASTM specification D 5798. If you have trouble
starting on E85, it could be because the E85 fuel is not
properly formulated for your climate. If this happens,
switching to gasoline or adding gasoline to the fuel tank
can improve starting. For good starting and heater
efficiency below 0°C (32°F), the fuel mix in the fuel tank
should contain no more than 70% ethanol. It is best not
to alternate repeatedly between gasoline and E85.
If you do switch fuels, it is recommended that you add
as much fuel as possible—do not add less than
11 L (three gallons) when refueling. You should drive
the vehicle immediately after refueling for at least
11 km (seven miles) to allow the vehicle to adapt to the
change in ethanol concentration.
E85 has less energy per gallon than gasoline, so you
will need to refill the fuel tank more often when using
E85 than when you are using gasoline. See Filling the
Tank on page 7‑10. Notice:
Some additives are not compatible with
E85 fuel and can harm the vehicle's fuel system.
Do not add anything to E85. Damage caused by
additives would not be covered by the vehicle
warranty.
Notice: This vehicle was not designed for fuel that
contains methanol. Do not use fuel containing
methanol. It can corrode metal parts in the fuel
system and also damage plastic and rubber parts.
That damage would not be covered under the
vehicle warranty.
Fuels in Foreign Countries
If you plan on driving in another country outside the
United States or Canada, the proper fuel might be hard
to find. 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 the vehicle 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.
7-9
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:
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.
{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.
7-12
A.Engine Air Cleaner/Filter on page 7‑20.
B. Coolant Surge Tank and Pressure Cap. See Cooling System on page 7‑26.
C. Remote Positive (+) Terminal. See Jump Starting
on page 7‑42.
D. Battery on page 7‑41.
E. Engine Oil Fill Cap. See “When to Add Engine Oil”
under Engine Oil on page 7‑15.
F. Automatic Transmission Dipstick (Out of View). See “Checking the Fluid Level” underAutomatic
Transmission Fluid on page 7‑22.
G. Remote Negative (−) Terminal (GND) (Out of View). See Jump Starting on page 7‑42.
H. Engine Oil Dipstick (Out of View). See “Checking
Engine Oil” underEngine Oil on page 7‑15.
I. Engine Cooling Fan (Out of View). See Cooling
System on page 7‑26.
J. Power Steering Fluid Reservoir (Out of View). See Power Steering Fluid on page 7‑36.
K. Brake Master Cylinder Reservoir. See “Brake
Fluid” under Brakes on page 7‑38.
L. Underhood Fuse Block on page 7‑108.
M. Windshield Washer Fluid Reservoir. See “Adding
Washer Fluid” underWindshield Washer Fluid
on
page 7‑37.
Engine Oil
Checking Engine Oil
It is a good idea to check the engine oil level at each
fuel fill. 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 7‑14for 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 this is not done, the
oil dipstick might not show the actual level.
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.
7-15
Engine Oil Additives / Engine Oil
Flushes
Do not add anything to the oil. The recommended oils
with the starburst symbol that meet GM standards 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 ENGINE OIL SOON message comes on.
See
DIC Warnings and Messages
on page 4‑48.
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 service 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.
7-18
Checking Coolant
The vehicle must be on a level surface when checking
the coolant level.
Check to see if coolant is visible in the coolant surge
tank. If the coolant inside the coolant surge tank is
boiling, do not do anything else until it cools down.
If coolant is visible but the coolant level is not at or
above the FULL COLD mark, add a 50/50 mixture of
clean, drinkable water and DEX-COOL
®coolant at the
coolant surge tank, but be sure the cooling system is
cool before this is done.
The coolant surge tank is located in the engine
compartment on the passenger side of the vehicle.
See Engine Compartment Overview
on page 7‑14for
more information on location.
The coolant level should be at or above the FULL
COLD mark. If it is not, you may have a leak in the
cooling system.
7-29