2008 GMC YUKON DENALI ECO mode

For models with a three passenger third row seat, see
the information following for installing a child restraint
with a top tether in the third row, if your vehicle has one.
Never install two top tethers using the same top
tether anchor.
For models with 60/40 second row seating, the rear
right side passenger and center seating positions have
exposed metal anchors located in the crease between
the seatback and the seat cushion.
For models with second row bucket seats, both rear
seating positions have exposed metal anchors located
in the crease between the seatback and the seat
cushion.
For models with bucket second row seating, the top
tether anchors are located at the bottom rear of the seat
cushion for each seating position in the second row.
Be sure to use an anchor located on the same side of
the vehicle as the seating position where the child
restraint will be placed.Second Row Seat — Bucket
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For models with 60/40 second row seating, the top
tether anchors are located at the bottom rear of the seat
cushion for each seating position in the second row.
Be sure to use an anchor located on the same side of
the vehicle as the seating position where the child
restraint will be placed.For vehicles with a two passenger third row seat, there
is one top tether anchor located at the bottom rear
of the seat cushion that can be used for the rear driver
side seating position in the third row. Never install
two top tethers using the same top tether anchor.
For vehicles with a three passenger third row seat, there
is one top tether anchor located at the bottom rear of
the seat cushion that can be used for either the third row
center or driver side seating position. Never install
two top tethers using the same top tether anchor. Second Row Seat — 60/40
Third Row Seat — Two or Three Passenger
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What Makes an Airbag Inate?
In a deployment event, the sensing system sends an
electrical signal triggering a release of gas from
the inator. Gas from the inator lls the airbag causing
the bag to break out of the cover and deploy. The
inator, the airbag, and related hardware are all part of
the airbag module.
Frontal airbag modules are located inside the steering
wheel and instrument panel. For vehicles with
roof-rail airbags, there are airbag modules in the ceiling
of the vehicle, near the side windows that have
occupant seating positions.
How Does an Airbag Restrain?
In moderate to severe frontal or near frontal collisions,
even belted occupants can contact the steering wheel or
the instrument panel. In moderate to severe side
collisions, even belted occupants can contact the inside
of the vehicle.
Airbags supplement the protection provided by safety
belts. Frontal airbags distribute the force of the
impact more evenly over the occupant’s upper body,
stopping the occupant more gradually. Roof-rail airbags
distribute the force of the impact more evenly over
the occupant’s upper body.
Rollover capable roof-rail airbags are designed to help
contain the head and chest of occupants in the
outboard seating positions in the rst, second, and third
rows, if equipped with a third row seat. The rollover
capable roof-rail airbags are designed to help reduce the
risk of full or partial ejection in rollover events, although
no system can prevent all such ejections.
But airbags would not help in many types of collisions,
primarily because the occupant’s motion is not
toward those airbags. SeeWhen Should an Airbag
Inflate? on page 1-81for more information.
Airbags should never be regarded as anything more
than a supplement to safety belts.
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DRIVE (D):This position is for normal driving. It
provides the best fuel economy for your vehicle. If you
need more power for passing, and you are:
Going less than about 35 mph (55 km/h), push your
accelerator pedal about halfway down.
Going about 35 mph (55 km/h) or more, push the
accelerator all the way down.
DRIVE (D) can be used when towing a trailer, carrying a
heavy load, driving on steep hills, or for off-road
driving. You may want to shift the transmission to a
lower gear selection if the transmission shifts too often.
Downshifting the transmission in slippery road
conditions could result in skidding, see “Skidding” under
Loss of Control on page 4-12
When temperatures are very cold, the Hydra-Matic
®
Automatic Transmission’s gear shifting may be delayed
providing more stable shifts until the engine warms
up. Shifts may be more noticeable with a cold
transmission. This difference in shifting is normal.
MANUAL MODE (M):This position lets drivers select
the range of gears appropriate for current driving
conditions. See Range Selection Mode later in
this section.Notice:Spinning the tires or holding the vehicle in
one place on a hill using only the accelerator
pedal may damage the transmission. The repair will
not be covered by your warranty. If you are stuck,
do not spin the tires. When stopping on a hill,
use the brakes to hold the vehicle in place.
Your vehicle has a shift stabilization feature that adjusts
the transmission shifting to the current driving conditions
in order to reduce rapid upshifts and downshifts. This shift
stabilization feature is designed to determine, before
making an upshift, if the engine will be able to maintain
vehicle speed by analyzing things such as throttle
position, vehicle load, and hill grade. If the shift
stabilization feature determines that a current vehicle
speed cannot be maintained, the transmission does not
upshift and instead holds the current gear. In some
cases, this may appear to be a delayed shift, however the
transmission is operating normally.
Your vehicle’s transmission uses adaptive shift controls.
Adaptive shift controls continually compares key shift
parameters to pre programmed ideal shift conditions
stored in the transmissions computer. The transmission
constantly makes adjustments to improve vehicle
performance according to the way the vehicle is being
used, such as with a heavy load. During this adaptive
shift controls process, some shifts may feel different as
the transmission determines the best settings for a
particular shift.
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Mirrors
Automatic Dimming Rearview Mirror
with OnStar
®, Compass and
Temperature Display
When on, an automatic dimming mirror automatically
dims to the proper level to minimize glare from
lights behind you after dark.
The mirror also includes a dual display in the upper
right corner of the mirror face. The compass reading and
the outside temperature will both appear in the display
at the same time.
P(On/Off):This is the on/off button.
Temperature and Compass Display
Press the on/off button, located to the far left, briey to
turn the compass/temperature display on or off.
If the display reads CAL, you will need to calibrate the
compass. For more information on calibration, see
below.To adjust between Fahrenheit and Celsius do the
following:
1. Press and hold the on/off button for approximately
four seconds until either a ashing F or C appears.
2. Press the button again to change the display to the
desired unit of measurement. After approximately
four seconds of inactivity, the new unit will be locked
in and the compass/temperature display will return.
If an abnormal temperature reading is displayed for an
extended period of time, please consult your dealer.
Under certain circumstances, a delay in updating
the temperature is normal.
Automatic Dimming Mirror Operation
The automatic dimming mirror function is turned on
automatically each time the ignition is started. To
operate the automatic dimming mirror, do the following:
1. Make sure the green indicator light, located to the left
of the on/off button, is lit. If it’s not, press and hold the
on/off button for approximately six seconds until the
green light comes on, indicating that the mirror is in
automatic dimming mode.
2. Turn off the automatic dimming mirror function by
pressing and holding the on/off button for
approximately six seconds, until the green indicator
light turns off.
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Compass Variance
The mirror is set in zone eight upon leaving the factory.
It will be necessary to adjust the compass to
compensate for compass variance if you live outside of
zone eight. Under certain circumstances, as during a
long distance cross-country trip, it will be necessary to
adjust for compass variance. Compass variance is
the difference between earth’s magnetic north and true
geographic north. If not adjusted to account for
compass variance, your compass could give false
readings.
To adjust for compass variance do the following:
1. Find your current location and variance zone
number on the following zone map.
2. Press and hold the on/off button until a Z and a
zone number appear in the display. The compass
is now in zone mode.
3. Keep pressing the on/off button until the desired
zone number appears in the display. Release the
button. After approximately four seconds of
inactivity, the new zone number will be locked in
and the compass/temperature display will return.
4. Calibrate the compass as described below.
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Universal Home Remote System
Operation (With Three Round LED)
Your vehicle may have the Universal Home Remote
System. If there are three round Light Emitting Diode
(LED) indicator lights above the Universal Home Remote
buttons, follow the instructions below.
This system provides a way to replace up to three
remote control transmitters used to activate devices
such as garage door openers, security systems,
and home automation devices.
Do not use this system with any garage door opener
that does not have the stop and reverse feature.
This includes any garage door opener model
manufactured before April 1, 1982.
Read the instructions completely before attempting to
program the transmitter. Because of the steps involved,
it may be helpful to have another person available to
assist you in programming the transmitter.Be sure to keep the original remote control transmitter
for use in other vehicles, as well as, for future
programming. You only need the original remote control
transmitter for Fixed Code programming. It is also
recommended that upon the sale or lease termination of
the vehicle, the programmed buttons should be
erased for security purposes. See “Erasing Universal
Home Remote Buttons” later in this section.
When programming a garage door, it is advised to park
outside of the garage. Be sure that people and
objects are clear of the garage door or security device
you are programming.Programming Universal Home
Remote — Rolling Code
If you have questions or need help programming the
Universal Home Remote System, call 1-866-572-2728 or
go to www.learcar2u.com.
Most garage door openers sold after 1996 are Rolling
Code units.
Programming a garage door opener involves
time-sensitive actions, so read the entire procedure
before you begin. If you do not follow these actions, the
device will time out and you will have to repeat the
procedure.
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2. Write down the eight to 12 switch settings from left
to right as follows:
When a switch is in the up position, write “Left.”
When a switch is in the down position, write
“Right.”
If a switch is set between the up and down
position, write “Middle.”
The switch settings that you wrote down in Step
2 will now become the button strokes you
enter into the Universal Home Remote in Step 4.
Be sure to enter the switch settings that you
wrote down in Step 2, in order from left to right,
into the Universal Home Remote, when
completing Step 4.
3. From inside your vehicle, rst rmly press all three
buttons at the same time for about three seconds.
Release the buttons to put the Universal Home
Remote into programming mode.4. The indicator lights will blink slowly. Enter each
switch setting from Step 2 into your vehicle’s
Universal Home Remote. You will have two and
one-half minutes to complete Step 4. Now
press one button on the Universal Home Remote
for each switch setting as follows:
If you wrote “Left,” press the left button in the
vehicle.
If you wrote “Right,” press the right button in the
vehicle.
If you wrote “Middle,” press the middle button in
the vehicle.
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