brake GMC ENVOY 2007 Owner's Guide

Remember: ABS 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 ABS.
Using ABS
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 ABS, you can steer and brake at the same
time. In many emergencies, steering can help you
more than even the very best braking.
Locking Rear Axle
If your vehicle has this feature, your locking rear
axle can give you additional traction on snow, mud,
ice, sand or gravel. It works like a standard axle
most of the time, but when one of the rear wheels
has no traction and the other does, this feature will
allow the wheel with traction to move the vehicle.
StabiliTrak®System
Your vehicle is equipped with StabiliTrak®,
Electronic Stability Control (ESC) which combines
antilock brake, traction and stability control systems
and helps the driver maintain directional control of
the vehicle in most driving conditions.
Traction control activates when the controller
senses wheel spin. StabiliTrak
®will selectively
apply the brakes and reduce engine torque to help
regain traction.
Stability control activates when the controller
senses a discrepancy between your intended path
and the direction the vehicle is travelling.
StabiliTrak
®selectively applies braking pressure at
any one of the vehicle’s brakes to help guide the
vehicle in the direction which you are steering.
When you rst start your vehicle and begin to drive
away, the system performs several diagnostic
checks to insure there are no problems. You may
hear or feel the system working. This is normal and
does not mean there is a problem with your vehicle.
If driving conditions delay system initialization, the
STABILITRAK NOT READY message may be
displayed. If this is the case, your vehicle does not
need servicing.
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Traction Control Off
In this mode, stability control and brake-traction
control are functional. Engine speed management
will be modied and the driven wheels can spin
more freely. This can cause the brake-traction
control to activate more frequently. If the controller
detects excessive wheel spin in this mode, the
StabiliTrak
®indicator light may blink and the
STABILITRAK ACTIVE message may be displayed
to warn the driver that damage may occur to the
transfer case.
StabiliTrak®Off
In this mode, both stability control and part of the
traction control system are disabled. Your vehicle
will still have brake-traction control, but will not be
able to use the engine speed management system.
You may still hear system noises as a result of the
brake-traction control coming on. If the controller
detects excessive wheel spin in this mode, the
StabiliTrak
®indicator light may blink and the
STABILITRAK ACTIVE message may be displayed
to warn the driver that damage may occur to the
transfer case.It is recommended to leave the system on for
normal driving conditions, but it may be necessary
to turn the system off if your vehicle is stuck in
sand, mud, ice or snow, and you may want
to “rock” your vehicle in an attempt to free it. It may
also be necessary to turn off the system when
driving in extreme off-road conditions where high
wheel spin is required. SeeIf Your Vehicle is
Stuck in Sand, Mud, Ice, or Snow on page 348for
more information.
When the transfer case is in 4LO, the stability
system is automatically disabled. The StabiliTrak
®
light will come on and the STABILITRAK OFF
message will appear on the DIC. The StabiliTrak®
system cannot be turned on until the vehicle is
switched to 2HI, 4HI, or 4AWD.
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The following chart describes the StabiliTrak®system events and the corresponding messages and lights
that will be displayed on the instrument panel cluster.
Vehicles with a DIC Vehicles without a DIC Event
StabiliTrak
®
Indicator LightDIC MessageStabiliTrak
®
Indicator LightStabiliTrak
®
Service Light—
Off None Off OffStabiliTrak
®On mode
(System is fully enabled, but
is not actively controlling
vehicle stability).
Solid Traction Control Off Solid OffTraction Control
Off Mode
Solid StabiliTrak
®Off Solid OffStabiliTrak
®Off Mode
(StabiliTrak®indicator light
will ash when system rst
enters this mode).
Blinking StabiliTrak
®Active Blinking OffStabiliTrak
®system activates
using engine speed
management, brake traction
control, and/or stability
control.
Solid Service StabiliTrak
®Solid SolidStabiliTrak
®system is
disabled due to a
system fault.
SolidStabiliTrak
®
Not ReadySolid OffStabiliTrak
®system is
disabled due to a failure
to initialize.
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Notice:If the StabiliTrak®light comes on
due to heavy braking and/or because the
traction control system has been continuously
active, do not allow the wheel(s) of one axle to
spin excessively. If you do, you may be causing
damage to the transfer case. This could lead to
costly repairs not covered by your warranty.
Notice:If you allow the wheel(s) of one axle
to spin excessively while the StabiliTrak
®,
ABS and brake warning lights and the
SERVICE STABILITRAK message are
displayed, you could damage the transfer
case. The repairs would not be covered by your
warranty. Reduce engine power and do not
spin the wheel(s) excessively while these lights
and this message are displayed.
StabiliTrak
®may activate on dry or rough roads or
under conditions such as heavy acceleration
while turning or abrupt upshifts/downshifts of the
transmission. When this happens, you may
notice a reduction in acceleration, or may hear a
noise or vibration. This is normal.If your vehicle is in cruise control when the system
activates, the StabiliTrak
®light will blink, and
the cruise control will automatically disengage.
When road conditions allow, you may re-engage
the cruise control. SeeCruise Control on
page 176.
StabiliTrak
®will turn off automatically if a problem
is detected in the system. The StabiliTrak®
light will come on and SERVICE STABILITRAK
will be displayed on the DIC. For vehicles without a
DIC, the StabiliTrak
®light and the StabiliTrak®
service light will both come on. If the SERVICE
STABILITRAK message (or StabiliTrak®service
light) does not clear itself after restarting the
vehicle, you should see your dealer for service.
Adding non-GM accessories can affect your
vehicle’s performance. SeeAccessories and
Modications on page 380for more information.
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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 306. 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.
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Watch for traffic signs, pavement markings, and
lines. If you can see a sign up ahead that might
indicate a turn or an intersection, delay your
pass. A broken center line usually indicates it is
all right to pass, providing the road ahead is
clear. Never cross a solid line on your side of
the lane or a double solid line, even if the road
seems empty of approaching traffic.
Do not get too close to the vehicle you want to
pass while you are awaiting an opportunity. For
one thing, following too closely reduces your
area of vision, especially if you are following a
larger vehicle. Also, you will not have adequate
space if the vehicle ahead suddenly slows or
stops. Keep back a reasonable distance.
When it looks like a chance to pass is coming
up, start to accelerate but stay in the right lane
and do not get too close. Time your move so
you will be increasing speed as the time comes
to move into the other lane. If the way is clear to
pass, you will have a running start that more
than makes up for the distance you would lose
by dropping back. And if something happens to
cause you to cancel your pass, you need only
slow down and drop back again and wait for
another opportunity.
If other vehicles are lined up to pass a slow
vehicle, wait your turn. But take care that
someone is not trying to pass you as you pull
out to pass the slow vehicle. Remember to
glance over your shoulder and check the
blind spot.
Check your vehicle’s mirrors, glance over your
shoulder, and start your left lane change signal
before moving out of the right lane to pass.
When you are far enough ahead of the passed
vehicle to see its front in your vehicle’s inside
mirror, activate the right lane change signal and
move back into the right lane. Remember that
your vehicle’s passenger side outside mirror is
convex. The vehicle you just passed may seem
to be farther away from you than it really is.
Try not to pass more than one vehicle at a time
on two-lane roads. Reconsider before passing
the next vehicle.
Do not overtake a slowly moving vehicle too
rapidly. Even though the brake lamps are not
ashing, it may be slowing down or starting
to turn.
If you are being passed, make it easy for the
following driver to get ahead of you. Perhaps
you can ease a little to the right.
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Loss of Control
Let us review what driving experts say about what
happens when the three control systems — brakes,
steering, and acceleration — do not have enough
friction where the tires meet the road to do what the
driver has asked.
In any emergency, do not give up. Keep trying to
steer and constantly seek an escape route or
area of less danger.
Skidding
In a skid, a driver can lose control of the vehicle.
Defensive drivers avoid most skids by taking
reasonable care suited to existing conditions, and
by not overdriving those conditions. But skids
are always possible.
The three types of skids correspond to your
vehicle’s three control systems. In the braking skid,
your wheels are not rolling. In the steering or
cornering skid, too much speed or steering in a
curve causes tires to slip and lose cornering force.
And in the acceleration skid, too much throttle
causes the driving wheels to spin.
A cornering skid is best handled by easing your
foot off the accelerator pedal.If your vehicle starts to slide, ease your foot off
the accelerator pedal and quickly steer the
way you want the vehicle to go. If you start
steering quickly enough, your vehicle may
straighten out. Always be ready for a second skid
if it occurs.
Of course, traction is reduced when water, snow,
ice, gravel, or other material is on the road.
For safety, you will want to slow down and adjust
your driving to these conditions. It is important
to slow down on slippery surfaces because
stopping distance will be longer and vehicle control
more limited.
While driving on a surface with reduced traction, try
your best to avoid sudden steering, acceleration, or
braking, including reducing vehicle speed by
shifting to a lower gear. Any sudden changes could
cause the tires to slide. You may not realize the
surface is slippery until your vehicle is skidding.
Learn to recognize warning clues — such as
enough water, ice, or packed snow on the road to
make a mirrored surface — and slow down when
you have any doubt.
Remember: Any Anti-Lock Brake System (ABS)
helps avoid only the braking skid.
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Q:What should I do if my vehicle stalls,
or is about to stall, and I cannot make it
up the hill?
A:If this happens, there are some things you
should do, and there are some things you
must not do. First, here is what youshoulddo:
Push the brake pedal to stop the vehicle
and keep it from rolling backwards. Also, apply
the parking brake.
If the engine is still running, shift the
transmission to REVERSE (R), release the
parking brake, and slowly back down the
hill in REVERSE (R).
If the engine has stopped running, you will need
to restart it. With the brake pedal pressed and
the parking brake still applied, shift the
transmission to PARK (P) and restart the
engine. Then, shift to REVERSE (R), release
the parking brake, and slowly back down the hill
as straight as possible in REVERSE (R).
As you are backing down the hill, put your left
hand on the steering wheel at the 12 o’clock
position. This way, you will be able to tell if the
wheels are straight and maneuver as you back
down. It is best that you back down the hill with
the wheels straight rather than in the left or right
direction. Turning the wheel too far to the left or
right will increase the possibility of a rollover.
Here are some things youmust notdo if you stall,
or are about to stall, when going up a hill.
Never attempt to prevent a stall by shifting
into NEUTRAL (N) to rev-up the engine
and regain forward momentum. This will not
work. Your vehicle will roll backwards
very quickly and you could go out of control.
Instead, apply the regular brake to stop
the vehicle. Then apply the parking brake.
Shift to REVERSE (R), release the parking
brake, and slowly back straight down.
Never attempt to turn around if you are about
to stall when going up a hill. If the hill is steep
enough to stall your vehicle, it is steep
enough to cause you to roll over if you turn
around. If you cannot make it up the hill, you
must back straight down the hill.
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Q:Suppose, after stalling, I try to back down
the hill and decide I just cannot do it.
What should I do?
A:Set the parking brake, put the transmission in
PARK (P) and turn off the engine. Leave the
vehicle and go get some help. Exit on the
uphill side and stay clear of the path the
vehicle would take if it rolled downhill. Do not
shift the transfer case to NEUTRAL when
you leave the vehicle. Leave it in some gear.
{CAUTION:
Shifting the transfer case to NEUTRAL can
cause your vehicle to roll even if the
transmission is in PARK (P). This is
because the NEUTRAL position on the
transfer case overrides the transmission.
You or someone else could be injured.
If you are going to leave your vehicle,
set the parking brake and shift the
transmission to PARK (P). But do not shift
the transfer case to NEUTRAL. Leave the
transfer case in the Two-Wheel High,
Four-Wheel High or Four-Wheel Low
position.
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Driving Downhill
When off-roading takes you downhill, you will want
to consider a number of things:
How steep is the downhill? Will I be able to
maintain vehicle control?
What is the surface like? Smooth? Rough?
Slippery? Hard-packed dirt? Gravel?
Are there hidden surface obstacles? Ruts?
Logs? Boulders?
What is at the bottom of the hill? Is there a
hidden creek bank or even a river bottom
with large rocks?If you decide you can go down a hill safely, then
try to keep your vehicle headed straight down, and
use a low gear. This way, engine drag can help
the brakes and they will not have to do all
the work. Descend slowly, keeping your vehicle
under control at all times.
{CAUTION:
Heavy braking when going down a hill can
cause your brakes to overheat and fade.
This could cause loss of control and a
serious accident. Apply the brakes lightly
when descending a hill and use a low
gear to keep vehicle speed under control.
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