height GMC YUKON 2012 User Guide

Black plate (50,1)GMC Yukon/Yukon XL Owner Manual - 2012
9-50 Driving and Operating
Continuous Damping
Control (CDC)
This vehicle may have a continuous
damping control system called
Autoride
®or MagneRide™. With
this feature, improved vehicle ride
and handling is provided under a
variety of passenger and loading
conditions.
Autoride and MagneRide are fully
automatic and use a computer
controller to continuously monitor
vehicle speed, wheel to body
position, lift/dive and steering
position of the vehicle. The
controller then sends signals to
each shock absorber to
independently adjust the damping
level to provide the optimum
vehicle ride. Autoride and MagneRide also
interact with the tow/haul mode that,
when activated, will provide
additional control of the shock
absorbers. This additional control
results in better ride and handling
characteristics when the vehicle is
loaded or towing a trailer. See
“Tow/
Haul Mode” underTrailer Towing on
page 9‑72 for more information.
Automatic Level Control
The automatic level control rear
suspension is available on light‐duty
vehicles and comes as a part of the
Continuous Damping Control (CDC)
suspension, if equipped.
This type of level control is fully
automatic and will provide a better
leveled riding position as well as
better handling under a variety of
passenger and loading conditions. An air compressor connected to the
rear shocks will raise or lower the
rear of the vehicle to maintain
proper vehicle height. The system is
activated when the ignition key is
turned to ON/RUN and will
automatically adjust vehicle height
thereafter. The system may exhaust
(lower vehicle height) for up to
ten minutes after the ignition key
has been turned off. You may hear
the air compressor operating when
the height is being adjusted.
If a weight‐distributing hitch is being
used, it is recommended to allow
the shocks to inflate, thereby
leveling the vehicle prior to adjusting
the hitch.

Black plate (55,1)GMC Yukon/Yukon XL Owner Manual - 2012
Driving and Operating 9-55
SBZA Detection Zones
The SBZA sensor covers a zone of
approximately one lane over from
both sides of the vehicle, 3.5 m
(11 ft). This zone starts at each side
mirror and goes back approximately
5.0 m (16 ft). The height of the
zone is approximately between
0.5 m (1.5 ft) and 2.0 m (6 ft) off the
ground.
Use caution while changing lanes
when towing a trailer, as the SBZA
detection zones do not change
when a trailer is towed.How the System Works
The SBZA symbol lights up in the
side mirrors when the system
detects a vehicle in the side blind
zone, indicating it may be unsafe to
change lanes. Before making a lane
change, check the SBZA display,
check all mirrors, glance over your
shoulder, and use the turn signals.
Left Side Mirror
DisplayRight Side Mirror Display
When the vehicle is started, both
outside mirror SBZA displays will
briefly come on to indicate the
system is operating. When the
vehicle is moving forward, the left or
right side mirror display will light up
if a vehicle is detected in that blind
zone. If the turn signal is activated
and a vehicle is also detected on the same side, the display will flash
to give you extra warning not to
change lanes.
At speeds greater then 32 km/h
(20 mph), SBZA displays may come
on when approaching or passing
other vehicles. SBZA displays may
come on when a passed vehicle
remains in or drops back into the
detection zone. SBZA can be
disabled through the Driver
Information Center (DIC). See
Driver
Information Center (DIC) on
page 5‑29. If SBZA is disabled by
the driver, the SBZA mirror displays
will not light up.
When the System Does Not Seem
To Work Properly
Missed alerts can occur under
normal circumstances and will
increase in wet conditions. The
system does not need to be
serviced. SBZA is designed to
ignore stationary objects; however,
the system may occasionally light
up due to guard rails, signs, trees,

Black plate (26,1)GMC Yukon/Yukon XL Owner Manual - 2012
10-26 Vehicle Care
Brakes
This vehicle has disc brakes. Disc
brake pads have built-in wear
indicators that make a high-pitched
warning sound when the brake pads
are worn and new pads are needed.
The sound can come and go or be
heard all the time the vehicle is
moving, except when applying the
brake pedal firmly.
{WARNING
The brake wear warning sound
means that soon the brakes will
not work well. That could lead to
a crash. When the brake wear
warning sound is heard, have the
vehicle serviced.
Notice: Continuing to drive with
worn-out brake pads could result
in costly brake repair. Some driving conditions or climates
can cause a brake squeal when the
brakes are first applied or lightly
applied. This does not mean
something is wrong with the brakes.
Properly torqued wheel nuts are
necessary to help prevent brake
pulsation. When tires are rotated,
inspect brake pads for wear and
evenly tighten wheel nuts in the
proper sequence to torque
specifications in
Capacities and
Specifications on page 12‑2.
Brake linings should always be
replaced as complete axle sets.
Brake Pedal Travel
See your dealer if the brake pedal
does not return to normal height,
or if there is a rapid increase in
pedal travel. This could be a sign
that brake service might be
required.
Brake Adjustment
Every time the brakes are applied,
with or without the vehicle moving,
the brakes adjust for wear.
Replacing Brake System Parts
The braking system on a vehicle is
complex. Its many parts have to be
of top quality and work well together
if the vehicle is to have really good
braking. The vehicle was designed
and tested with top-quality brake
parts. When parts of the braking
system are replaced, be sure to get
new, approved replacement parts.
If this is not done, the brakes might
not work properly. For example,
installing disc brake pads that are
wrong for the vehicle, can change
the balance between the front and
rear brakes —for the worse. The
braking performance expected can
change in many other ways if the
wrong replacement brake parts are
installed.

Black plate (36,1)GMC Yukon/Yukon XL Owner Manual - 2012
10-36 Vehicle Care
4. At a wall, measure from theground upward (A) to the
recorded distance from
Step 3 and mark it.
5. Draw or tape a horizontal line (B) on the wall the width of the
vehicle at the height of the mark
in Step 4.
Notice: Do not cover a headlamp
to improve beam cut-off when
aiming. Covering a headlamp may
cause excessive heat build-up
which may cause damage to the
headlamp. 6. Turn on the low-beam
headlamps and place a piece of
cardboard or equivalent in front
of the headlamp not being
adjusted. This allows only the
beam of light from the headlamp
being adjusted to be seen on the
flat surface.
7. Locate the vertical headlamp
aiming screws, which are under
the hood near each headlamp
assembly.
The adjustment screw can be
turned with an E8 Torx
®socket. 8. Turn the vertical aiming screw
until the headlamp beam is
aimed to the horizontal
tape line. Turn it clockwise or
counterclockwise to raise or
lower the angle of the beam.
9. Make sure that the light from theheadlamp is positioned at the
bottom edge of the horizontal
tape line. The lamp on the
left (A) shows the correct
headlamp aim. The lamp on the
right (B) shows the incorrect
headlamp aim.
10. Repeat Steps 7 through 9 for the opposite headlamp.

Black plate (50,1)GMC Yukon/Yukon XL Owner Manual - 2012
10-50 Vehicle Care
Tire Sidewall Labeling
Useful information about a tire is
molded into the sidewall. The
examples show a typical
passenger and light truck tire
sidewall.
Passenger (P‐Metric) Tire
(A) Tire Size:The tire size
code is a combination of letters
and numbers used to define a
particular tire's width, height,
aspect ratio, construction type, and service description. See the
“Tire Size”
illustration later in this
section for more detail.
(B) TPC Spec (Tire
Performance Criteria
Specification)
:Original
equipment tires designed to
GM's specific tire performance
criteria have a TPC specification
code molded onto the sidewall.
GM's TPC specifications meet or
exceed all federal safety
guidelines.
(C) DOT (Department of
Transportation)
:The
Department of Transportation
(DOT) code indicates that the
tire is in compliance with
the U.S. Department of
Transportation Motor Vehicle
Safety Standards. (D) Tire Identification Number
(TIN)
:The letters and numbers
following the DOT code are the
Tire Identification Number
(TIN). The TIN shows the
manufacturer and plant code,
tire size, and date the tire was
manufactured. The TIN is
molded onto both sides of the
tire, although only one side may
have the date of manufacture.
(E) Tire Ply Material
:The type
of cord and number of plies in
the sidewall and under the tread.
(F) Uniform Tire Quality
Grading (UTQG)
:Tire
manufacturers are required to
grade tires based on three
performance factors: treadwear,
traction, and temperature
resistance. For more
information, see Uniform Tire
Quality Grading on page 10‑66.

Black plate (51,1)GMC Yukon/Yukon XL Owner Manual - 2012
Vehicle Care 10-51
(G) Maximum Cold Inflation
Load Limit
:Maximum load
that can be carried and the
maximum pressure needed
to support that load. For
information on recommended
tire pressure see Tire Pressure
on page 10‑56 andVehicle Load
Limits on page 9‑16.
Light Truck (LT-Metric) Tire
(A) Tire Size:The tire size
code is a combination of letters
and numbers used to define a
particular tire's width, height, aspect ratio, construction type,
and service description. See the
“Tire Size”
illustration later in this
section for more detail.
(B) TPC Spec (Tire
Performance Criteria
Specification)
:Original
equipment tires designed to
GM's specific tire performance
criteria have a TPC specification
code molded onto the sidewall.
GM's TPC specifications meet or
exceed all federal safety
guidelines.
(C) Dual Tire Maximum Load
:
Maximum load that can be
carried and the maximum
pressure needed to support
that load when used in a dual
configuration. For information on
recommended tire pressure see
Tire Pressure on page 10‑56
andVehicle Load Limits on
page 9‑16. (D) DOT (Department of
Transportation)
:The
Department of Transportation
(DOT) code indicates that
the tire is in compliance with
the U.S. Department of
Transportation Motor Vehicle
Safety Standards.
(E) Tire Identification Number
(TIN)
:The letters and numbers
following the DOT code are the
Tire Identification Number
(TIN). The TIN shows the
manufacturer and plant code,
tire size, and date the tire was
manufactured. The TIN is
molded onto both sides of the
tire, although only one side may
have the date of manufacture.
(F) Tire Ply Material
:The type
of cord and number of plies in
the sidewall and under the tread.

Black plate (52,1)GMC Yukon/Yukon XL Owner Manual - 2012
10-52 Vehicle Care
(G) Single Tire Maximum
Load
:Maximum load that can
be carried and the maximum
pressure needed to support that
load when used as a single. For
information on recommended
tire pressure see Tire Pressure
on page 10‑56 andVehicle Load
Limits on page 9‑16.
Tire Designations
Tire Size
The examples show a typical
passenger vehicle and light
truck tire size.
Passenger (P‐Metric) Tire
(A) Passenger (P‐Metric) Tire:
The United States version of a
metric tire sizing system. The letter P as the first character in
the tire size means a passenger
vehicle tire engineered to
standards set by the U.S. Tire
and Rim Association.
(B) Tire Width
:The three‐digit
number indicates the tire section
width in millimeters from
sidewall to sidewall.
(C) Aspect Ratio
:A two‐digit
number that indicates the tire
height‐to‐width measurements.
For example, if the tire size
aspect ratio is 75, as shown in
item C of the tire illustration,
it would mean that the tire's
sidewall is 75 percent as high
as it is wide.
(D) Construction Code
:A
letter code is used to indicate
the type of ply construction in
the tire. The letter R means
radial ply construction; the
letter D means diagonal or bias ply construction; and the
letter B means belted‐bias ply
construction.
(E) Rim Diameter
:Diameter of
the wheel in inches.
(F) Service Description
:These
characters represent the load
index and speed rating of the
tire. The load index represents
the load carrying capacity a tire
is certified to carry. The speed
rating is the maximum speed a
tire is certified to carry a load.
Light Truck (LT‐Metric) Tire
(A) Light Truck (LT‐Metric)
Tire
:The United States
version of a metric tire sizing
system. The letters LT as the
first two characters in the tire

Black plate (53,1)GMC Yukon/Yukon XL Owner Manual - 2012
Vehicle Care 10-53
size mean a light truck tire
engineered to standards
set by the U.S. Tire and Rim
Association.
(B) Tire Width
:The three‐digit
number indicates the tire section
width in millimeters from
sidewall to sidewall.
(C) Aspect Ratio
:A two‐digit
number that indicates the tire
height‐to‐width measurements.
For example, if the tire size
aspect ratio is 75, as shown
in item C of the light truck
(LT‐Metric) tire illustration, it
would mean that the tire's
sidewall is 75 percent as high
as it is wide. (D) Construction Code
:A
letter code is used to indicate
the type of ply construction in
the tire. The letter R means
radial ply construction; the
letter D means diagonal or bias
ply construction; and the letter B
means belted‐bias ply
construction.
(E) Rim Diameter
:Diameter of
the wheel in inches.
(F) Load Range
:Load Range.
(G) Service Description
:The
service description indicates the
load index and speed rating of a
tire. If two numbers are given as
in the example, 120/116, then
this represents the load index for
single versus dual wheel usage
(single/dual). The speed rating is
the maximum speed a tire is
certified to carry a load.
Tire Terminology and
Definitions
Air Pressure:The amount of
air inside the tire pressing
outward on each square inch
of the tire. Air pressure is
expressed in kPa (kilopascal)
or psi (pounds per square inch).
Accessory Weight
:The
combined weight of optional
accessories. Some examples
of optional accessories are
automatic transmission, power
steering, power brakes, power
windows, power seats, and air
conditioning.
Aspect Ratio
:The relationship
of a tire's height to its width.
Belt
:A rubber coated layer of
cords that is located between
the plies and the tread. Cords
may be made from steel or other
reinforcing materials.

Black plate (69,1)GMC Yukon/Yukon XL Owner Manual - 2012
Vehicle Care 10-69
{WARNING
Using the wrong replacement
wheels, wheel bolts, or wheel
nuts can be dangerous. It could
affect the braking and handling of
the vehicle. Tires can lose air,
and cause loss of control, causing
a crash. Always use the correct
wheel, wheel bolts, and wheel
nuts for replacement.Notice:
The wrong wheel can
also cause problems with bearing
life, brake cooling, speedometer
or odometer calibration,
headlamp aim, bumper height,
vehicle ground clearance, and tire
or tire chain clearance to the
body and chassis.
See If a Tire Goes Flat on
page 10‑71 for more information.
Used Replacement Wheels
{WARNING
Replacing a wheel with a used
one is dangerous. How it has
been used or how far it has been
driven may be unknown. It could
fail suddenly and cause a crash.
When replacing wheels, use a
new GM original equipment
wheel.