brakes GMC ENVOY XL 2005 Owners Manual

{CAUTION:
It is dangerous to get out of your vehicle if
the shift lever is not fully in PARK (P) with the
parking brake rmly set. Your vehicle can roll.
Do not 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.
To be sure your vehicle will not move, even
when you are on fairly level ground, always
set your parking brake and move the shift
lever to PARK (P). SeeShifting Into Park (P)
on page 2-32. If you are pulling a trailer, see
Towing a Trailer on page 4-55.
{CAUTION:
If you have four-wheel drive, your vehicle
will be free to roll — even if your shift lever
is in PARK (P) — if your transfer case is in
NEUTRAL. So, be sure the transfer case is in a
drive gear — not in NEUTRAL. SeeFour-Wheel
Drive on page 2-27. SeeShifting Into Park (P)
on page 2-32.
Ensure the shift lever is fully in PARK (P) before starting
the engine. Your vehicle has an automatic transmission
shift lock control system. You have to fully apply the
regular brakes before you can shift from PARK (P)
when the ignition key is in RUN. If you cannot shift
out of PARK (P), ease pressure on the shift lever,
press the button on the shift lever and push the shift
lever all the way into PARK (P) as you maintain brake
application. Move the shift lever into the gear you
wish. SeeShifting Out of Park (P) on page 2-34.
2-25

SECOND (2):This position gives you more power
but lower fuel economy than THIRD (3). 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 the brakes off and on.
You can also use SECOND (2) for starting the vehicle
from a stop on slippery road surfaces.
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
selector lever is put in FIRST (1) while the vehicle
is moving forward, the transmission will not shift into
rst gear until the vehicle is going slowly enough.
Notice:Spinning the tires or holding the vehicle
in one place on a hill using only the accelerator
pedal may damage the transmission. If you
are stuck, do not spin the tires. When stopping
on a hill, use the brakes to hold the vehicle in place.Four-Wheel Drive
If your vehicle has four-wheel drive, you can send your
engine’s driving power to all four wheels for extra
traction. To get the most satisfaction out of four-wheel
drive, you must be familiar with its operation. Read
the part that follows before using four-wheel drive.
You should use 2HI (two-wheel high) for most normal
driving conditions.
Notice:Driving on clean, dry pavement in
four-wheel drive for an extended period of time may
cause premature wear on your vehicle’s powertrain.
Do not drive on clean, dry pavement in four-wheel
drive for extended periods of time.
2-27

Shifting Out of Park (P)
Your vehicle has an automatic transmission shift lock
control system. You have to fully apply the regular
brakes before you can shift from PARK (P) when the
ignition is in RUN. SeeAutomatic Transmission
Operation on page 2-24.
Parking Over Things That Burn
{CAUTION:
Things that can burn could touch hot exhaust
parts under your vehicle and ignite. Do not
park over papers, leaves, dry grass or other
things that can burn.
2-34

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 shut off.
{CAUTION:
Cruise control can be dangerous where you
cannot drive safely at a steady speed. So, do
not 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. Do not use cruise
control on slippery roads.
{CAUTION:
If you leave your cruise control on when you
are not using cruise, you might hit a button
and go into cruise when you do not want to.
You could be startled and even lose control.
Keep the cruise control switch off until you
want to use cruise control.
Setting Cruise Control
1. Move the cruise control switch to on.
2. Get up to the speed you want.
3. Press the set button at the end of the lever
and release it.
4. Take your foot off the accelerator pedal.
The accelerator pedal will not go down.
3-12

Anti-Lock Brake System
Warning Light
With the anti-lock brake
system, this light will come
on when you start your
engine and may stay on
for several seconds.
That’s normal. A chime
may also sound when
the light comes on.
If the light stays on, or comes on when you’re driving,
your vehicle needs service. 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. SeeBrake System Warning Light on page 3-38
earlier in this section.
The anti-lock brake system warning light should come
on briey when you turn the ignition key to RUN.
If the light doesn’t come on then, have it xed so it
will be ready to warn you if there is a problem.
Engine Coolant Temperature Gage
This gage shows the engine coolant temperature. If the
gage pointer moves into the red area, it means that
your engine coolant has overheated. If you have been
operating your vehicle under normal driving conditions,
you should pull off the road, stop your vehicle and
turn off the engine as soon as possible.
SeeEngine Overheating on page 5-26for more
information.
United StatesCanada
3-40

{CAUTION:
Drinking and then driving is very dangerous.
Your reexes, perceptions, attentiveness, and
judgment 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 do not drink and drive or ride with a
driver who has been drinking. Ride home in a
cab; or if you are with a group, designate a
driver who will not drink.
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.
Sometimes, as when you are driving on snow or ice, it
is easy to ask more of those control systems than
the tires and road can provide. That means you can
lose control of your vehicle.
Braking
Braking action involves perception time and
reaction time.
First, you have to decide to push on the brake pedal.
That is perception time. Then you have to bring up your
foot and do it. That is reaction time.
Average reaction time is about three-fourths of a
second. But that is 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 three-fourths 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 is pavement
or gravel; the condition of the road, whether it is
wet, dry, or icy; tire tread; the condition of your brakes;
the weight of the vehicle; and the amount of brake
force applied.
4-5

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 are driving, brake
normally but do not 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.Anti-Lock Brake System (ABS)
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 is a problem with
the anti-lock brake system,
this warning light will
stay on. SeeAnti-Lock
Brake System Warning
Light on page 3-40.
Along with ABS, your vehicle has a Dynamic Rear
Proportioning (DRP) system. If there is a DRP problem,
both the brake and ABS warning lights will come on
accompanied by a 10-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.
4-6

Let us say the road is wet and you are driving safely.
Suddenly, an animal jumps out in front of you. You slam
on the brakes and continue braking. Here is 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.The anti-lock system can change the brake pressure
faster than any driver could. The computer is
programmed to make the most of available tire and road
conditions. This can help you steer around the obstacle
while braking hard.
As you brake, your computer keeps receiving updates
on wheel speed and controls braking pressure
accordingly.
4-7

Remember: Anti-lock does not change the time you
need to get your foot up to the brake pedal or always
decrease stopping distance. If you get too close to
the vehicle in front of you, you will not have time to apply
your brakes if that vehicle suddenly slows or stops.
Always leave enough room up ahead to stop, even
though you have anti-lock brakes.
Using Anti-Lock
Do not pump the brakes. Just hold the brake pedal
down rmly and let anti-lock work for you. You may feel
the brakes vibrate, or you may notice some noise,
but this is normal.
Braking in Emergencies
With anti-lock brakes, you can steer and brake at the
same time. In many emergencies, steering can help you
more than even the very best braking.
Traction Assist System (TAS)
Your two-wheel drive vehicle may have a Traction
Assist System (TAS) that limits wheel spin. This
is especially useful in slippery road conditions. The
system operates only if it senses that one or both of the
rear wheels are spinning or beginning to lose traction.
When this happens, the system reduces engine
power to limit wheel spin.The low traction symbol next to the button will come on
when the TAS is limiting wheel spin. You may feel or
hear the system working, but this is normal.
The Traction Assist System may operate on dry roads
under some conditions. When this happens, you
may notice a reduction in acceleration. This is normal
and doesn’t mean there’s a problem with your vehicle.
Examples of these conditions include a hard
acceleration in a turn, an abrupt upshift or downshift of
the transmission or driving on rough roads.
If your vehicle is in cruise control when the TAS begins
to limit wheel spin, the cruise control will automatically
disengage. When road conditions allow you to safely
use it again, you may re-engage the cruise control. See
Cruise Control on page 3-11.
When the traction control
off symbol on the button is
on, the TAS is off and
will not limit wheel
spin. Adjust your
driving accordingly.
4-8

Steering in Emergencies
There are times when steering can be more effective
than braking. For example, you come over a hill and nd
a truck stopped in your lane, or a car suddenly pulls
out from nowhere, or a child darts out from between
parked cars and stops right in front of you. You
can avoid these problems by braking — if you can stop
in time. But sometimes you cannot; there is not room.
That is the time for evasive action — steering around
the problem.
Your vehicle can perform very well in emergencies like
these. First apply your brakes.
SeeBraking on page 4-5. It is better to remove as much
speed as you can from a possible collision. Then
steer around the problem, to the left or right depending
on the space available.An emergency like this requires close attention and a
quick decision. If you are holding the steering wheel at
the recommended 9 and 3 o’clock positions, you
can turn it a full 180 degrees very quickly without
removing either hand. But you have to act fast, steer
quickly, and just as quickly straighten the wheel
once you have avoided the object.
The fact that such emergency situations are always
possible is a good reason to practice defensive driving
at all times and wear safety belts properly.
4-11