2010 GMC YUKON 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 4‑37.
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 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
This vehicle 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 has 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. See
Cruise Control on page 4‑7.
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
Driver Information Center (DIC), the vehicle should be
taken in for service. For more information on the DIC
messages, see Driver Information Center (DIC)
on
page 4‑47.
5-6

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.
In this mode, engine power is not reduced automatically
and the driven wheels can spin more freely. This can
cause the brake-traction control to activate constantly.
Notice:If the wheel(s) of one axle is allowed to spin
excessively while the StabiliTrak, ABS and brake
warning lights and any relevant DIC messages are
displayed, the transfer case could be damaged.
The repairs would not be covered by the vehicle
warranty. Reduce engine power and do not spin
the wheel(s) excessively while these lights and
messages are displayed. The traction control system 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, a reduction in
acceleration may be noticed, or a noise or vibration may
be heard. This is normal.
If cruise control is being used when the system
activates, the StabiliTrak light will flash and cruise
control will automatically disengage. Cruise control
may be reengaged when road conditions allow.
See
Cruise Control on page 4‑7.
StabiliTrak may also turn off automatically if it
determines that a problem exists with the system.
If the problem does not clear itself after restarting
the vehicle, see your dealer for service.
Locking Rear Axle
Vehicles with a locking rear axle can give more traction
on snow, mud, ice, sand or gravel. It works like a
standard axle most of the time, but when traction is low,
this feature will allow the rear wheel with the most
traction to move the vehicle.
5-8

Steering
Power Steering
If the vehicle is a Two‐mode Hybrid, see the Two‐mode
Hybrid manual for more information.
If power steering assist is lost because the engine stops
or the system is not functioning, the vehicle can be
steered but it will take more effort.
Steering Tips
It is important to take curves at a reasonable speed.
Traction in a curve depends on the condition of the tires
and the road surface, the angle at which the curve is
banked, and vehicle speed. While in a curve, speed is
the one factor that can be controlled.
If there is a need to reduce speed, do it before entering
the curve, while the front wheels are straight.
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.
5-9

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.
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.
5-11

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.
Off-roading can be great fun but has some definite
hazards. The greatest of these is the terrain itself. When
off-road driving, traffic lanes are not marked, curves are
not banked, and there are no road signs. Surfaces can
be slippery, rough, uphill, or downhill.
Avoid sharp turns and abrupt maneuvers. Failure to
operate the vehicle correctly off‐road could result in loss
of vehicle control or vehicle rollover.
Off-roading involves some new skills. That is why it is
very important that you read these driving tips and
suggestions to help make off-road driving safer and
more enjoyable.
5-12

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.
{WARNING:
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. Things not to do when driving down a hill:
.When driving downhill, avoid turns that take you
across the incline of the hill. A hill that is not too
steep to drive down might be too steep to drive
across. The vehicle could roll over.
.Never go downhill with the transmission in
N (Neutral), called free-wheeling. The brakes
will have to do all the work and could overheat
and fade.
Vehicles are much more likely to stall when going uphill,
but if it happens when going downhill: 1. Stop the vehicle by applying the regular brakes and apply the parking brake.
2. Shift to P (Park) and, while still braking, restart the engine.
3. Shift back to a low gear, release the parking brake, and drive straight down.
4. If the engine will not start, get out and get help.
5-20