2007 GMC SIERRA CLASSIC fuel

Recommended Transfer Case Settings
Driving
ConditionsTransfer Case Settings
2
mAUTO
4WD4m4nN
Normal YES
Variable YES
Severe YES
Extreme YES
Vehicle in
Tow*YES
*SeeRecreational Vehicle Towing on page 424for
further information.
You can choose among ve driving settings:
Notice:Driving on clean, dry pavement in
Four-Wheel-Drive High or Four-Wheel-Drive
Low for an extended period of time may cause
premature wear on your vehicle’s powertrain.
Do not drive on clean, dry pavement in
Four-Wheel-Drive High or Four-Wheel-Drive
Low for extended periods of time.Indicator lights in the switches show the current
setting. The indicator lights will come on briey
when you turn on the ignition and the last chosen
setting will stay on. If the lights do not come
on, you should take your vehicle to your dealer for
service. An indicator light will ash while shifting.
Fast ashing means the conditions are not
being met to make the desired shift, typically the
vehicle is going too fast, the automatic
transmission is not in NEUTRAL, or the clutch
pedal is not fully pressed. Slow ashing means the
shift is in progress. It will stay on when the shift
is completed. If for some reason the transfer case
cannot make a requested shift, it will return to
the last chosen setting.
AUTO 4WD (Automatic Four-Wheel Drive):This
setting is ideal for use when road surface
traction conditions are variable. When driving your
vehicle in AUTO 4WD, the front axle is engaged,
but the vehicle’s power is primarily sent to the rear
wheels. When the vehicle’s software determines
a need for more traction, the system will
transfer more power to the front wheels. Driving in
this mode results in slightly lower fuel economy
than Two-Wheel Drive High.
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2m(Two-Wheel Drive High):This setting is
used for driving in most street and highway
situations. Your front axle is not engaged in
two-wheel drive. This setting also provides the best
fuel economy.
{CAUTION:
Shifting the transfer case to NEUTRAL
can cause your vehicle to roll even if the
transmission is in PARK (P). You or
someone else could be seriously injured.
Be sure to set the parking brake before
placing the transfer case in NEUTRAL.
SeeParking Brake on page 169.
N (NEUTRAL):Shift the vehicle’s transfer case to
N (NEUTRAL) only when towing your vehicle.
SeeRecreational Vehicle Towing on page 424or
Towing Your Vehicle on page 423for more
information.4
m(Four-Wheel Drive High):Use this setting
when you need extra traction, such a on snowy
or icy roads or in most off-road situations.
This setting also engages your front axle to help
drive the vehicle. This is the best setting to
use when plowing snow.
4
n(Four-Wheel Drive Low):This setting also
engages the front axle and delivers extra
torque. You may never need Four-Wheel Drive
Low. It sends maximum power to all four wheels.
You might choose Four-Wheel Drive Low if
you are driving off-road in deep sand, deep mud,
deep snow, and while climbing or descending
steep hills. When operating in Four-Wheel Drive
Low, the gear ratio provides additional torque
when compared to Four-Wheel Drive High. The
transmission gear shift feel will be exaggerated.
If the SERVICE 4WD message stays on the Driver
Information Center (DIC), you should take your
vehicle to your dealer for service. SeeDIC
Warnings and Messages on page 270for further
information.
159

Anti-Lock Brake System Warning Light...... 255
Traction Off Light...................................... 256
Engine Coolant Temperature Gage............ 256
Transmission Temperature Gage............... 257
Malfunction Indicator Lamp........................ 258
Oil Pressure Gage..................................... 262
Security Light............................................ 263
Cruise Control Light.................................. 263
Highbeam On Light................................... 263
Four-Wheel-Drive Light.............................. 263
Tow/Haul Mode Light................................ 264
Cargo Lamp Light..................................... 264
Fuel Gage................................................. 264
Low Fuel Warning Light............................ 265
Driver Information Center (DIC).................. 265
DIC Operation and Displays...................... 266
DIC Warnings and Messages.................... 270
DIC Vehicle Customization........................ 282Audio System(s)......................................... 289
Setting the Time for Radios without
Radio Data Systems (RDS).................... 290
Setting the Time for Radios with
Radio Data Systems (RDS).................... 291
AM-FM Radio............................................ 291
Radio with CD........................................... 294
Radio with Cassette and CD..................... 304
Radio with Six-Disc CD............................. 318
XM Radio Messages................................. 332
Rear Seat Entertainment System............... 334
Rear Seat Audio (RSA)............................. 347
Theft-Deterrent Feature............................. 348
Audio Steering Wheel Controls.................. 349
Radio Reception........................................ 350
Care of the Cassette Tape Player............. 350
Care of Your CDs and DVDs.................... 352
Care of the CD and DVD Player............... 352
Fixed Mast Antenna.................................. 353
XM™ Satellite Radio Antenna System....... 353
Chime Level Adjustment............................ 353
Section 3 Instrument Panel
208

Instrument Panel Cluster
Your instrument cluster is designed to let you know at a glance how your vehicle is running. You will
know how fast you are going, about how much fuel you have and many other things you will need to know
to drive safely and economically.
United States Heavy Duty Automatic Transmission version shown. Canada, Light Duty Automatic and Manual
Transmission Clusters similar.
245

Battery Warning Light
If this light comes on
when the engine is
running, there could be
a problem with the
charging system.
The battery display will also stay on while the key
is in RUN until the engine is started.
If the light stays on after starting the engine it
could indicate a problem with the generator drive
belt, or some other charging system problem.
Have it checked right away. Driving while this light
is on could drain the battery.
If you must drive a short distance with this light
on, it helps to turn off all your accessories, such as
the radio and the air conditioner.
Voltmeter Gage
When the engine is not
running, but the ignition
is in RUN, this gage
shows your battery’s
state of charge in
DC volts.
While the engine is running, this gage shows the
condition of the charging system. The gage
may transition from a higher to lower or a lower to
higher reading. This is normal. Readings
between the low and high warning zones indicate
the normal operating range. The voltmeter
gage may also read lower when in fuel economy
mode. This is normal.
Readings in the low warning zone may occur
when a large number of electrical accessories are
operating in the vehicle and the engine is left at
an idle for an extended period.
253

This condition is normal since the charging system
is not able to provide full power at engine idle.
As engine speeds are increased, this condition
should correct itself as higher engine speeds allow
the charging system to create maximum power.
You can only drive for a short time with the reading
in either warning zone. If you must drive, turn off
all unnecessary accessories.
Readings in either warning zone indicate a
possible problem in the electrical system. Have
the vehicle serviced as soon as possible.
Up-Shift Light
(Manual Transmission)
Your vehicle may have
an up-shift light.
It will come on when you should shift to the next
highest gear. It will help the vehicle get the
best fuel economy.
Brake System Warning Light
With the ignition on, the brake system warning
light will ash when you set the parking brake. The
light will ash if the parking brake does not
release fully. If you try to drive with the parking
brake engaged, a chime will sound when the
vehicle speed is greater than 3 mph (5 km/h).
Your vehicle’s hydraulic brake system is divided
into two parts. If one part is not working, the other
part can still work and stop you. For good
braking, though, you need both parts working well.
If the warning light comes on and a chime
sounds there could be a brake problem. Have
your brake system inspected right away.
United StatesCanada
254

If the transmission continues to operate above
265°F (130°C), contact your nearest dealer or the
GM Roadside Assistance Center. SeeRoadside
Assistance Program on page 644.
Notice:If you drive your vehicle with the
transmission temperature gage above normal
operating range, you can damage the
transmission. This could lead to costly repairs
that would not be covered by your warranty.
Do not drive your vehicle while the
transmission temperature gage reading is
above normal. See your dealer for service.
The following situations can cause the
transmission to operate at higher temperatures:
Towing a trailer
Hot outside air temperatures
Hauling a large or heavy load
Low transmission uid level
High transmission uid level
Restricted air ow to the radiator and the
auxiliary transmission oil cooler, if equipped.A temporary solution to reduce hotter transmission
operating temperatures may be to let the
transmission cool down. If the transmission is
operated at higher temperatures on a frequent
basis, seeScheduled Maintenance (Gasoline
Engine) on page 617for the proper transmission
maintenance intervals.
Malfunction Indicator Lamp
Check Engine Light
Your vehicle has a
computer which
monitors operation of
the fuel, ignition,
and emission control
systems.
258

This system is called OBD II (On-Board
Diagnostics-Second Generation) and is intended
to assure that emissions are at acceptable
levels for the life of the vehicle, helping to produce
a cleaner environment. The check engine light
comes on to indicate that there is a problem and
service is required. Malfunctions often will be
indicated by the system before any problem is
apparent. This may prevent more serious damage
to your vehicle. This system is also designed to
assist your service technician in correctly
diagnosing any malfunction.
Notice:If you keep driving your vehicle with
this light on, after awhile, your emission
controls may not work as well, your fuel
economy may not be as good, and your engine
may not run as smoothly. This could lead to
costly repairs that may not be covered by your
warranty.
Notice:Modications made to the engine,
transmission, exhaust, intake, or fuel system
of your vehicle or the replacement of the
original tires with other than those of the same
Tire Performance Criteria (TPC) can affect
your vehicle’s emission controls and may
cause this light to come on. Modications tothese systems could lead to costly repairs not
covered by your warranty. This may also
result in a failure to pass a required Emission
Inspection/Maintenance test. SeeAccessories
and Modifications on page 468.
This light should come on, as a check to show
you it is working, when the ignition is on and the
engine is not running. If the light does not
come on, have it repaired. This light will also
come on during a malfunction in one of two ways:
Light Flashing— A misre condition has
been detected. A misre increases vehicle
emissions and may damage the emission
control system on your vehicle. Diagnosis and
service may be required.
Light On Steady— An emission control
system malfunction has been detected on your
vehicle. Diagnosis and service may be
required.
259