trailer GMC YUKON DENALI 2003 Owners Manual

Starting and Operating Your
Vehicle
New Vehicle Break-In
Notice: Your vehicle doesn’t need an elaborate
“break-in.’’ But
it will perform better in the long run
if you follow these guidelines:
e
e
Keep your speed at 55 mph (88 km/h) or less for
the first
500 miles (805 km).
Don’t drive at any one speed
- fast or
slow
- for the first 500 miles (805 km).
Don’t make full-throttle starts.
Avoid making hard stops for the first
200 miles
(322 km) or so. During this time your new
brake linings aren’t yet broken in. Hard stops
with new linings can mean premature wear and
earlier replacement. Follow this breaking-in
guideline every time you get new brake linings.
Don’t tow a trailer during break-in. See “Towing
a Trailer” in the Index for more information.
Ignition Positions
With your key in the ignition switch you can turn it to
four different positions.
I C
A-
A (LOCK): This position locks your ignition and
transmission. It’s a theft-deterrent feature. You
will only
be able
to remove your key when the ignition is
turned to
LOCK.
2-1 8

Automatic Transmission Operation
Your vehicle is equipped with an automatic transmission
and features an electronic shift position indicator
located within the instrument panel cluster.
There are several different positions for your shift lever.
PARK
(P): This position locks your drive wheels. It’s
the best position to use when you start your engine
because your -1icle
c ’t move easily.
It is aangerous to get out of your venlcle il
shift lever is not fully in PARK (P) with the
parking brake firmly set. Your vehicle can roll.
Don’t leave your vehicle when the engine is
running unless you have to.
If you have left the
engine running, the vehicle can move
suddenly. You or others could be injured.
CAUTION: (Continued)
o be sure your vehicle won’t move, even
when you’re on fairly level ground, always set
your parking brake and move the shift lever to PARK (P). See “Shifting Into Park (P)” in the
Index.
If you’re pulling a trailer, see “Towing a
Trailer” in the Index.
REVERSE (R): Use this gear to back up.
Notices Shifting to REVERSE (R) while your vehicle
is moving forward could damage your transmission.
Shift to REVERSE
(R) only after your vehicle is
stopped.
To rock your vehicle back and forth to get out of snow,
ice or sand without damaging your transmission,
see If
You Are Stuck: In Sand, Mud, Ice or Snow on
page 4-4 1.
NEUTRAL (N): In this position, your engine doesn’t
connect with the wheels. To restart when you’re already
moving, use NEUTRAL
(N) only.
2-22

Shifting into a drive gear while your engine is
“racing” (running at high speed) is dangerous.
Unless your foot is firmly on the brake pedal,
your vehicle could move very rapidly. You
could lose control and hit people or objects.
Don’t shift into a drive gear while your engine
is racing.
Notices Damage to your transmission caused by
shifting out of PARK (P) or NEUTRAL (N) with
the engine racing isn’t covered by your warranty.
DRIVE (D):
This position is for normal driving. If
you need more power for passing, and you’re:
accelerator pedal about halfway down.
accelerator all the way down.
0 Going less than about 35 mph (55 km/h), push your
Going about 35 mph (55 km/h) or more, push the
You’ll shift down
to the next gear and have more power.
DRIVE (D) can be used when towing a trailer, carrying
a heavy load, driving on steep hills or for off-road driving.
You may want
to shift the transmission to THIRD (3)
or, if necessary, a lower gear selection if the
transmission shifts
too often.
THIRD (3): This position is also used for normal driving,
however it offers more power and lower fuel economy
than DRIVE (D).
SECOND (2): This position gives you more power but
lower fuel economy. You can use SECOND
(2) on
hills.
It can help control your speed as you go down
steep mountain roads, but then you would also want
to
use your brakes off and on.
If you manually select SECOND
(2), the transmission
will drive in second gear. You may use this feature
for reducing the speed of the rear wheels when you are
trying
to start your vehicle from a stop on slippery
road surfaces. Once the vehicle
is moving, shift into
DRIVE
(D).
FIRST (1): This position gives you even more power,
but lower fuel economy than SECOND
(2). You can use
it on very steep hills, or in deep snow or mud. If the
shift lever is put in FIRST
(1) while the vehicle is moving
forward, the vehicle won’t shift into first gear until the
vehicle is going slowly enough.
2-23

Notice: If your wheels won’t turn, don’t try to drive.
This might happen
if you were stuck in very deep
sand or mud or were up against
a solid object. You
could damage your transmission. Also, if you
stop when going uphill, don’t hold your vehicle there
with only the accelerator pedal. This could overheat
and damage the transmission. Use your brakes
or shift into
PARK (P) to hold your vehicle in
position on
a hill.
On cold days, approximately
32°F (OOC) or colder, your
transmission is designed
to shift differently until the
engine reaches normal operating temperature. This is
intended
to improve heater performance.
Tow/HauI Mode
Your vehicle is equipped with a tow/haul mode. The
button is located on the end
of the column shift lever.
You can use this feature
to assist when towing or
hauling a heavy load. See “Tow/Haul Mode” under
Towing
a Trailer on page 4-47 for more information.
The tow/haul mode also interacts with the AutorideTM
feature
to enhance the ride when trailering or with
a loaded vehicle. See AutorideTM on page
4-46.
2-24

Parking Brake
To set the parking brake, hold the regular brake pedal
down with your right foot. Push down the parking
brake pedal with your left foot.
A chime will activate and the warning light will flash
when the parking brake is applied and the vehicle
is moving at
least 3 mph (5 km/h) for at least three
seconds.
To release the parking brake, hold the regular brake
pedal down.
Pull the bottom edge of the lever, located
above the parking brake pedal, with the parking
brake symbol,
to release the parking brake.
If the ignition is on when the parking brake is releasea,
the brake system warning light will go
off.
Notice: Driving with the parking brake on can
cause your rear brakes to overheat. You may have
to replace them, and you could also damage
other parts
of your vehicle.
If you are towing a trailer and are parking on any hill,
see Towing a Trailer on page
4-47.
2-25

Shifting Into Park (P)
It can be dangerous to get out of your vehicle
if the shift lever is not fully in
PARK (P) with
the parking brake firmly set. Your vehicle can
roll. If you have left the engine running, the
vehicle can move suddenly. You or others
could be injured.
To be sure your vehicle won’t
move, even when you’re on fairly level ground,
use the steps that follow.
If you’re pulling a
trailer, see “Towing a Trailer’’ in the Index.
1. Hold the brake pedal down with your right foot and
set the parking brake.
2. Move the shift lever into PARK (P) like this:
Pull the shift lever toward you.
2-26

Running Your Engine While You
Are Parked
It’s better not to park with the engine running. But if you
ever have
to, here are some things to know.
Id g the en- le with the climate co ,ol
system off could allow dangerous exhaust into
your vehicle. See the earlier Caution under
“Engine Exhaust.”
Also, idling in a closed-in place can let deadly
carbon monoxide (CO) into your vehicle even
if
the fan is at the highest setting. One place this
can happen is a garage. Exhaust
- with CO -
can come in easily. NEVER park in a garage
with
the engine running.
Another closed-in place can be a blizzard. See
“Winter Driving”
in the Index.
It can be dangerous to get out of your vehicle
if the shift lever is not fully in PARK (P) with
the parking brake firmly set. Your vehicle can
roll. Don’t leave your vehicle when the engine
is running unless you have to.
If you’ve left the
engine running, the vehicle can move
suddenly. You or others could be injured.
To
be sure your vehicle won’t move, even when
you’re on fairly level ground, always set your
parking brake and move
the shift lever to
PARK (P).
Follow the proper steps to be sure your vehicle won’t
move. See Shifting lnto Park
(P) on page 2-26.
If you’re pulling a trailer, see Towing a Trailer on
page
4-47.
2-30

Transmission Temperature Gage
--
United States Canada
Your vehicle is equipped with a transmission
temperature gage.
When your ignition is on, the gage shows the
temperature of the transmission fluid. The normal
operating range is from
100°F (38°C) to about 265°F
(1 30°C).
At approximately 265°F (130°C), the DIC will display a
TRANSMISSION HOT message and the transmission
will enter a transmission protection mode. When
the transmission enters the protection mode, you may
notice a change in the transmission shifting patterns.
The transmission will return to normal shifting patterns
when the transmission fluid temperature falls below
260°F
(1 27°C). See
Driver Information
Center (DIC) on page 3-43 for
further information.
If the transmission fluid reaches temperatures of
approximately 275°F (135°C) or greater, the DIC will
display a TRANS
HOT tDLE ENGtNE warning message
and a chime will sound. Pull the vehicle
off the
roadway when it is safe
to do so. Set the parking brake,
place the transmission in PARK
(P) and allow the
engine to idle until the transmission temperature falls
below 260°F (127°C).
If the transmission continues
to operate above 265°F
(1 30"C), please contact your
nearest dealer or the
GM Roadside Assistance Center.
Notice: If you keep driving your vehicle with the
transmission temperature gage above the normal
operating range, you can damage the transmission.
This could lead to costly repairs that may not be
covered under your warranty.
The following situations can cause the transmission to
operate at higher temperatures:
0 Towing a trailer,
* hot outside air temperatures,
0 hauling a large or heavy load,
low transmission fluid level,
high transmission fluid level,
0 restricted air flow to the radiator.

Light On Steady - An emission control system
malfunction has been detected on your vehicle.
Dealer or qualified service center diagnosis
and service may be required.
If the Light is Flashing
The following may prevent more serious damage to
your vehicle:
Reducing vehicle speed.
Avoiding hard accelerations.
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 Filling
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.

Tow/HauI Mode Light
I
This light is displayed
when the tow/haul mode
has been activated.
For more information, see "Tow/Haul Mode" under
Towing a Trailer on page 4-47.
Fuel Gage
United States
Canada
When the ignition is on, the fuel gage tells you about
how much fuel you have left in your tank.
The gage will first indicate empty before you are out of
fuel, and you should get more fuel as
soon as
possible.
Here are some situations you may experience with your
fuel gage. None of these indicate a problem with the
fuel gage.
At the gas station, the fuel pump shuts off before
the gage reads full.
It takes a little more or less fuel to fill up than the
fuel gage indicated. For example, the gage may
have indicated the tank was half full, but
it actually
took a little more or less than half the tank's
capacity to
fill the tank.
The gage goes back to empty when you turn off the
ignition.
Low Fuel Warning Light
The light next to the fuel gage will come on briefly when
you are starting the engine.
This light comes on when the fuel tank is
low on fuel.
To turn it off, add fuel to the fuel tank. See Fuel on
page 5-5.
3-42