2010 GMC SIERRA brakes

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.
The brakes might not have time to cool between hard
stops. The brakes will wear out much faster with a lot
of heavy braking. Keeping pace with the traffic and
allowing realistic following distances eliminates a lot of
unnecessary braking. That means better braking and
longer brake life.
If the engine ever stops while the vehicle is being
driven, brake normally but do not pump the brakes.
If the brakes are pumped, the pedal could get harder to
push down. If the engine stops, there will still be some
power brake assist but it will be used when the brake is
applied. Once the power assist is used up, it can take
longer to stop and the brake pedal will be harder
to push.
Adding non‐dealer/non‐retailer accessories can affect
vehicle performance. SeeAccessories and
Modifications on page 6‑4.Antilock Brake System (ABS)
This vehicle has the Antilock Brake System (ABS), an
advanced electronic braking system that helps prevent
a braking skid.
When the engine is started and the vehicle begins to
drive away, ABS checks itself. A momentary motor or
clicking noise might be heard while this test is going on.
This is normal.
If there is a problem with
ABS, this warning light
stays on. See Antilock
Brake System (ABS)
Warning Light
on
page 4‑40.
Along with ABS, the vehicle has a Dynamic Rear
Proportioning (DRP) system. If there is a DRP problem,
both the brake and ABS warning lights 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/retailer
for service.
5-4

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 the 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.
ABS can change the brake pressure to each wheel, as
required, faster than any driver could. This can help the
driver steer around the obstacle while braking hard.
As the brakes are applied, the computer keeps
receiving updates on wheel speed and controls braking
pressure accordingly.
Remember: ABS does not change the time needed to
get a foot up to the brake pedal or always decrease
stopping distance. If you get too close to the vehicle in
front of you, there will not be enough time to apply the
brakes if that vehicle suddenly slows or stops. Always
leave enough room up ahead to stop, even with ABS.
Using ABS
Do not pump the brakes. Just hold the brake pedal
down firmly and let antilock work. The brakes might
vibrate or some noise might be heard, but this is
normal.
Braking in Emergencies
ABS allows the driver to steer and brake at the same
time. In many emergencies, steering can help more
than even the very best braking.
Brake Assist (Except With 4.3L V6 Engine)
If this vehicle has StabiliTrak®, it also has a Brake
Assist feature designed to assist the driver in stopping
or decreasing vehicle speed in emergency driving
conditions. This feature uses the stability system
hydraulic brake control module to supplement the
power brake system under conditions where the driver
has quickly and forcefully applied the brake pedal in
an attempt to quickly stop or slow down the vehicle.
The stability system hydraulic brake control module
increases brake pressure at each corner of the vehicle
until the ABS activates. Minor brake pedal pulsations or
pedal movement during this time is normal and the
driver should continue to apply the brake pedal as the
driving situation dictates The Brake Assist feature
will automatically disengage when the brake pedal is
released or brake pedal pressure is quickly decreased.
5-5

StabiliTrak®System
The vehicle may have a vehicle stability enhancement
system called StabiliTrak. It is an advanced computer
controlled system that assists the driver with directional
control of the vehicle in difficult driving conditions.
StabiliTrak activates when the computer senses a
discrepancy between the intended path and the
direction the vehicle is actually traveling. StabiliTrak
selectively applies braking pressure at any one of the
vehicle's brakes to assist the driver with keeping the
vehicle on the intended path.
When the vehicle is started and begins to move, the
system performs several diagnostic checks to insure
there are no problems. The system may be heard or felt
while it is working. This is normal and does not mean
there is a problem with the vehicle. The system should
initialize before the vehicle reaches 20 mph (32 km/h).
In some cases, it may take approximately two miles of
driving before the system initializes.
If cruise control is being used when StabiliTrak
activates, the cruise control automatically disengages.
The cruise control can be re-engaged when road
conditions allow. SeeCruise Control
on page 4‑7for
more information. If the system fails to turn on or activate, the StabiliTrak
light along with one of the following messages will be
displayed on the Driver Information Center (DIC):
TRACTION CONTROL OFF, SERVICE TRACTION
CONTROL, STABILITRAK OFF, SERVICE
STABILITRAK. If these DIC messages appear, make
sure the StabiliTrak system has not been turned off
using the StabiliTrak on/off button. Then turn the
steering wheel clockwise from the nine o'clock position
to the three o'clock position. If this clears the
message(s), the vehicle does not need servicing. If this
does not clear the message(s), then turn the vehicle off,
wait 15 seconds, and then turn it back on again to reset
the system. If any of these messages still appear on the
DIC, the vehicle should be taken in for service. For
more information on the DIC messages, see
DIC
Warnings and Messages on page 4‑65.
The StabiliTrak light will
flash on the instrument
panel cluster when the
system is both on and
activated.
The system may be heard or felt while it is working; this
is normal.
5-6

The traction control
disable button is located
on the instrument panel
below the climate
controls.
The traction control part of StabiliTrak can be turned
off by pressing and releasing the StabiliTrak button if
both systems (traction control and StabiliTrak) were
previously on. To disable both TCS and StabiliTrak,
press and hold the button for five seconds.
TCS and StabiliTrak can be turned on by pressing and
releasing the StabiliTrak button if not automatically shut
off for any other reason.
When TCS or StabiliTrak is turned off, the StabiliTrak
light and the appropriate message will be displayed on
the DIC to warn the driver. The vehicle will still have
brake-traction control when traction control is off, but
will not be able to use the engine speed management
system. See “Traction Control Operation” next for
more information.
When the traction control system has been turned off,
system noises may still be heard as a result of the
brake-traction control coming on. It is recommended to leave the system on for normal
driving conditions, but it may be necessary to turn the
system off if the vehicle is stuck in sand, mud, ice or
snow, and you want to
“rock”the vehicle to 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. See If Your Vehicle is Stuck in
Sand, Mud, Ice, or Snow on page 5‑28.
When the transfer case is in 4LO, the stability system is
automatically disabled, the StabiliTrak light comes on
and the STABILITRAK OFF message will appear on the
DIC. Both traction control and StabiliTrak are
automatically disabled in this condition.
Traction Control Operation
The traction control system is part of the StabiliTrak
system. Traction control limits wheel spin by reducing
engine power to the wheels (engine speed
management) and by applying brakes to each individual
wheel (brake-traction control) as necessary.
The traction control system is enabled automatically
when the vehicle is started. It will activate and the
StabiliTrak light will flash if it senses that any of the
wheels are spinning or beginning to lose traction while
driving. If traction control is turned off, only the
brake-traction control portion of traction control will
work. The engine speed management will be disabled.
5-7

Try to adjust the speed so you can drive through the
curve. Maintain a reasonable, steady speed. Wait to
accelerate until out of the curve, and then accelerate
gently into the straightaway.
Steering in Emergencies
There are times when steering can be more effective
than braking. For example, you come over a hill and
find 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.
These problems can be avoided by braking—if you can
stop in time. But sometimes you cannot stop in time
because there is no room. That is the time for evasive
action —steering around the problem.
The vehicle can perform very well in emergencies
like these. First, apply the brakes. See Braking
on
page 5‑3. It is better to remove as much speed as
possible from a 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 holding the steering wheel at the
recommended 9 and 3 o'clock positions, it can be
turned 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.
5-9

Off-Road Recovery
The vehicle's right wheels can drop off the edge of a
road onto the shoulder while driving.
If the level of the shoulder is only slightly below the
pavement, recovery should be fairly easy. Ease off the
accelerator and then, if there is nothing in the way, steer
so that the vehicle straddles the edge of the pavement.
Turn the steering wheel 8 to 13 cm (3 to 5 inches),
about one-eighth turn, until the right front tire contacts
the pavement edge. Then turn the steering wheel to go
straight down the roadway.
Passing
Passing another vehicle on a two-lane road can be
dangerous. To reduce the risk of danger while passing:
.Look down the road, to the sides, and to
crossroads for situations that might affect a
successful pass. If in doubt, wait.
.Watch for traffic signs, pavement markings, and
lines that could indicate a turn or an intersection.
Never cross a solid or double‐solid line on your
side of the lane.
.Do not get too close to the vehicle you want to
pass. Doing so can reduce your visibility.
.Wait your turn to pass a slow vehicle.
.When you are being passed, ease to the right.
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.
5-10

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 the vehicle's
three control systems. In the braking skid, the 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.
Remember: StabiliTrak
®helps avoid only the
acceleration skid. See StabiliTrak®Systemon
page 5‑6. If the StabiliTrak®System is off, then an
acceleration skid is best handled by easing your foot off
the accelerator pedal.
If the 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,
the 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, 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 the 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: Antilock brakes help avoid only the
braking skid.
Off-Road Driving
Vehicles with four-wheel drive can be used for off-road
driving. Vehicles without four-wheel drive and vehicles
with 20‐inch tire/wheel assemblies should not be driven
off-road except on a level, solid surface.
The airbag system is designed to work properly under
a wide range of conditions, including off‐road usage.
Always wear your safety belt and observe safe driving
speeds, especially on rough terrain.
Drinking and driving can be very dangerous on any
road and this is certainly true for off-road driving. At the
very time you need special alertness and driving skills,
your reflexes, perceptions, and judgment can be
affected by even a small amount of alcohol. You could
have a serious —or even fatal —accident if you drink
and drive or ride with a driver who has been drinking.
5-11

If, after stalling, you try to back down the hill and decide
you just cannot do it, set the parking brake, put your
transmission in P (Park), 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.
{WARNING:
Shifting the transfer case to Neutral can cause
your vehicle to roll even if the transmission is
in P (Park). 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 P (Park). But do not
shift the transfer case to Neutral.
Driving Downhill
When off-roading takes you downhill, consider:
.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, try to keep
the vehicle headed straight down. Use a low gear so
engine drag can help the brakes so they do not have to
do all the work. Descend slowly, keeping the vehicle
under control at all times.
5-18