brakes GMC YUKON DENALI 2003 Owners Manual

These are some examples of vehicle symbols you may find on your vehicle:
CAUTION
POSSIBLE
INJURY
PROTECT EYES BY
SHIELDING
CAUSTIC
BATTERY
ACID COULD CAUSE
BURNS
AVO ID
SPARKS
OR
FLAMES
SPARK
OR
FLAME '\I/'
COULD
EXPLODE BATTERY LATCH BOTH LAP AND
SHOULDER BELTS TO
PROTECT OCCUPANT
4
DO NOT TWIST SAFETY
BELT WHEN ATTACHING
FASTEN SEAT
BELTS
MOVE SEAT DO NOT INSTALL
A REAR-FACING
CHILD RESTRAINT
SECURE IN THIS SEATING
CHILD SEAT POSITION
FULLY
c REARWARD+ /3
PULL BELT DO NOT INSTALL A
COMPLETELY
THEN SECURE
CHILD SEAT FORWARD-FACING
CHILD RESTRAINT IN THIS SEATING
POSITION
POWER DOOR LOCK
WINDOW UNLOCK LIGHTING
- MASTER SWITCH u- 0 ,
LAMPS #O
ENGINE
COOLANT
-FA TEMP -
CHARGING Fl
BATTERY
SYSTEM
ENGINE OIL PRESSURE
9%77
ANTI-LOCK (@)
BRAKES
FUSE BOX
ACCESS
ENGINE
COOLANT FAN
OWNER'S MANUAL
SERVICE
SERVICE MANUAL
V

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

Torque Lock
If you are parking on a hill and you don’t shift your
vehicle into PARK (P) properly, the weight of the vehicle
may put
too much force on the parking pawl in the
transmission. You may find it difficult
to pull the shift
lever
out of PARK (P). This is called torque lock.
To prevent torque lock, set the parking brake and then
shift into PARK (P) properly before you leave the
driver’s seat. To find
out how, see Shifting lnto Park (P)
on page 2-26.
When you are ready to drive, move the shift lever out of
PARK (P) before you release the parking brake.
If torque lock does occur, you may need
to have another
vehicle push yours a little uphill
to take some of the
pressure from the parking pawl in the transmission,
so
you can pull the shift lever out of PARK (P).
Shifting Out of Park (P)
Your vehicle has an automatic transmission shift lock
control system. You have
to fully apply your regular
brakes before you can shift from PARK (P) when the
ignition is in RUN. See Automatic Transmission
Operation
on page 2-22.
If you cannot shift out of PARK (P), ease pressure on
the shift lever and push the shift lever all the way up into
PARK (P) as you maintain brake application. Then,
move the shift lever into the gear you want.
If you ever hold the brake pedal down but still can’t shift
out of PARK (P), try this:
1. Turn the key to LOCK.
2. Apply and hold the brake until the end of Step 4.
3. Shift the vehicle to NEUTRAL (N).
4. Start the vehicle and then shift to the drive gear
you want.
5. Have the system fixed as soon as you can.
2-28

Cruise Control
0 (Off): This position
turns the system
off.
I (On): This position activates the system.
+ (Resume/Accelerate): Push the lever to this symbol
to make the vehicle accelerate or resume to a
previously set speed. (Set):
Press this button to set the speed.
With cruise control, you can maintain a speed of about
25 mph (40 km/h) or more without keeping your foot
on the accelerator. This can really help on long
trips. Cruise control does not work at speeds below
about
25 mph (40 km/h).
If you apply your brakes, the cruise control will shl
~ff.
Cruise control can be dangerous where
you can’t drive safely at
a steady speed.
So, don’t use your cruise control on
winding roads or in heavy traffic.
Cruise control can be dangerous on
slippery roads. On such roads, fast
changes
in tire traction can cause
needless wheel spinning, and you could lose control. Don’t use cruise control on
slippery roads.
3-1 0

If the light stays on, or comes on when you’re driving,
your vehicle needs service. You will also hear a
chime sound when the light is on steady.
If the regular
brake system warning light isn’t on, you still have
brakes, but you don’t have anti-lock brakes.
If the
regular brake system warning light is also on you don’t
have anti-lock brakes and there’s a problem with
your regular brakes. In addition to both lights, you will
also hear a chime sound on the first occurrence of
a problem and each time the car is shut off and then
restarted. See Brake System Warning Light on
page
3-34.
Traction Off Light
If you have the
Stabilitrak@system, this
light should come on briefly
when you turn the
ignition to
RUN.
If the light doesn’t come on then, the system may
require service; have it fixed
so it will be there to warn
you
if the system is turned off.
For more information on the traction off light, see
Stabilitrak@
System on page 4-9.
3-36
Engine Coolant Temperature Gage
~~ ~
United States
I I
Canada
This gage shows the engine coolant temperature.
It also provides an indicator
of how hard your vehicle is
working. During a majority of the operation, the gage
will read 21
0°F (100°C) or less. If you are pulling a load
or going up hills, it is normal for the temperature to
fluctuate and approach the 250°F (122°C) mark.
If the
gage reaches the 260°F
(125°C) mark, it indicates
that the cooling system
is working beyond its capacity.
See Engine Overheating on page
5-25.

There’s something else about drinking and driving that many people don’t know. Medical research shows
that alcohol in a person’s system can make crash
injuries worse, especially injuries to the brain, spinal
cord or heart. This means that when anyone who
has been drinking
- driver or passenger - is in a
crash, that person’s chance
of being killed or
permanently disabled is higher than
if the person had
not been drinking.
Control of a Vehicle
You have three systems that make your vehicle go
where you want it to go. They are the brakes, the
steering and
the accelerator. All three systems have to
do their work at the places where the tires meet
the road.
Drinking and
t n drivinc_ ; very -1ngerous.
Your reflexes, perceptions, attentiveness and
judgement can be affected by even a small amount of alcohol. You can have a serious-or
even fatal-collision if you drive after drinking. Please don’t drink and drive or ride with a
driver who has been drinking. Ride home in a
cab;
or if you’re with a group, designate a
driver who will not drink.
Sometimes, as when you’re driving
on snow or ice, it’s
easy
to ask more of those control systems than the
tires and road can provide. That means you can lose
control of your vehicle.
4-5

Braking
Braking action involves perception time and
reaction time.
First, you have
to decide to push on the brake pedal.
That’s perception time. Then you have
to bring up your
foot and do it. That’s reaction time.
Average reaction time is about 314 of a second. But
that’s only an average.
It might be less with one driver
and as long as two or three seconds or more with
another. Age, physical condition, alertness, coordination
and eyesight all play a part.
So do alcohol, drugs and
frustration.
But even in 3/4 of a second, a vehicle moving
at 60 mph
(100 km/h) travels 66 feet (20 m). That
could be a
lot of distance in an emergency, so keeping
enough space between your vehicle and others is
important.
And, of course, actual stopping distances vary greatly
with the surface of the road (whether it’s pavement
or gravel); the condition of the road (wet, dry, icy); tire
tread; the condition of your brakes; the weight of
the vehicle and the amount of brake force applied. Avoid needless heavy
braking. Some people drive in
spurts
- heavy acceleration followed by heavy
braking
- rather than keeping pace with traffic. This is
a mistake. Your brakes may not have time
to cool
between hard stops. Your brakes will wear out much
faster
if you do a lot of heavy braking. If you keep pace
with the traffic and allow realistic following distances,
you will eliminate a
lot of unnecessary braking.
That means better braking and longer brake life.
If your engine ever stops while you’re driving, brake
normally but don’t pump your brakes.
If you do,
the pedal may get harder
to push down. If your engine
stops, you will still have some power brake assist.
But you will use it when you brake. Once the power
assist is used up, it may take longer
to stop and
the brake pedal will be harder
to push.
4-6

Anti-lock Brake System
Your vehicle has anti-lock brakes. ABS is an advanced
electronic braking system that will help prevent a
braking skid.
When you start your engine and begin to drive away,
your anti-lock brake system will check itself. You
may hear a momentary motor or clicking noise while
this test is going on. This is normal.
If there’s a problem with
the anti-lock brake system, this warning light
will
stay on. See Anti-Lock
Brake System Warning
Light
on page 3-35.
Along with ABS, your vehicle has a Dynamic Rear
Proportioning (DRP) system.
If there’s a DRP problem,
both the brake and ABS warning lights will come
on
accompanied by a IO-second chime. The lights
and chime will come
on each time the ignition is turned
on until the problem is repaired. See your dealer for
service. Let’s say
the road is wet and you’re driving safely.
Suddenly, an animal jumps out in front of you. You slam
on the brakes and continue braking. Here’s what
happens with ABS:
A computer senses that wheels are slowing down. If
one of the wheels is about to stop rolling, the computer
will separately work the brakes at each front wheel
and at both rear wheels.
4-7