
A.Outlet Adjustment on page 4‑29.
B. Turn Signal/Multifunction Lever on page 4‑4.
C. Driver Information Center (DIC) Buttons. See Driver Information Center (DIC) on page 4‑51.
D. Hazard Warning Flashers on page 4‑3.
E. Instrument Panel Cluster on page 4‑30.
F. Shift Lever. See Automatic Transmission Operation
on page 3‑28. Tow/Haul Selector Button
(If Equipped). See Tow/Haul Modeon page 3‑34.
Range Selection Mode (Allison Transmission and
Hydra-Matic
®6‐Speed Button (If Equipped). See
Automatic Transmission Operation on page 3‑28.
G. Audio System(s) on page 4‑84.
H. Instrument Panel Storage on page 3‑76.
I. Integrated Trailer Brake Controller (If Equipped). See Towing a Trailer on page 5‑50.
J. Exterior Lamps on page 4‑10.
K. Hood Release on page 6‑15.
L. Parking Brake on page 3‑50.
M. Dome Lamp Override
on page 4‑15.Dome Lampson page 4‑14.Fog Lampson page 4‑13(If Equipped).
N. Cruise Control on page 4‑7.
O. Tilt Wheel on page 4‑3. P.
Horn on page 4‑3.
Q. Audio Steering Wheel Controls
on page 4‑145(If Equipped).
R. Automatic Transfer Case Control (If Equipped). See Four-Wheel Drive on page 3‑36.
S. Ashtray (If Equipped). See Ashtray(s) and
Cigarette Lighter on page 4‑18.
T. StabiliTrak
®Systemon page 5‑6(If Equipped).
Ultrasonic Rear Parking Assist (URPA)on
page 3‑60(If Equipped). Pedal Adjust Button
(If Equipped). See Adjustable Throttle and Brake
Pedal
on page 3‑26. Heated Windshield Washer
Fluid Button (If Equipped). Windshield Washeron
page 4‑6.
U. Accessory Power Outlet(s) on page 4‑17.
V. Climate Control System (With Heater Only)
on
page 4‑18or Climate Control System (With Air
Conditioning)on page 4‑20and Dual Automatic
Climate Control System on page 4‑22.
W. Power Take Off (PTO) Control (If Equipped). See Power Take Off (PTO) in the Duramax Diesel
Supplement Index.
X. Passenger Airbag Off Control (If Equipped). See Airbag Off Switch on page 2‑82.
Y. Glove Box on page 3‑75.
1-3

A.Outlet Adjustment on page 4‑29.
B. Turn Signal/Multifunction Lever on page 4‑4.
C. Instrument Panel Cluster on page 4‑30.
D. Hazard Warning Flashers
on page 4‑3.
E. Shift Lever. See Automatic Transmission Operation
on page 3‑28.
F. Tow/Haul Mode
on page 3‑34(If Equipped).
G. Driver Information Center (DIC) Buttons. See Driver Information Center (DIC) on page 4‑51.
H. Audio System(s) on page 4‑84.
I. Exterior Lamps on page 4‑10.
J. Integrated Trailer Brake Controller (If Equipped). See Towing a Trailer on page 5‑50.
K. Dome Lamp Override
on page 4‑15.Dome Lampson page 4‑14.
L. Automatic Transfer Case Control. (If Equipped). See Four-Wheel Drive on page 3‑36.
M. Hood Release on page 6‑15.
N. Parking Brake on page 3‑50. O.
Cruise Control on page 4‑7.
P. Tilt Wheel on page 4‑3.
Q. Horn on page 4‑3.
R. Audio Steering Wheel Controls on page 4‑145.
S. Climate Control System (With Heater Only)
on
page 4‑18or Climate Control System (With Air
Conditioning)on page 4‑20or Dual Automatic
Climate Control Systemon page 4‑22(If Equipped).
T. Accessory Power Outlet(s)
on page 4‑17.
Cigarette Lighter (If Equipped). See Ashtray(s) and
Cigarette Lighter
on page 4‑18.
U. StabiliTrak®Systemon page 5‑6(If Equipped).
Pedal Adjust Button (If Equipped). See Adjustable
Throttle and Brake Pedal
on page 3‑26. Ultrasonic
Rear Parking Assist (URPA)on page 3‑60(If Equipped). Heated Windshield Washer Fluid
Button (If Equipped). See Windshield Washeron
page 4‑6.
V. Passenger Airbag Off Control (If Equipped). See Airbag Off Switch on page 2‑82.
W. Glove Box on page 3‑75.
1-5

Fuel Used
Press the trip/fuel button until FUEL USED displays.
This display shows the number of gallons (gal) or
liters (L) of fuel used since the last reset of this menu
item. To reset the fuel used information, press and hold
the set/reset button while FUEL USED is displayed.
Timer
Press the trip/fuel button until TIMER displays.
This display can be used as a timer.
To start the timer, press the set/reset button while
TIMER is displayed. The display will show the amount
of time that has passed since the timer was last reset,
not including time the ignition is off. Time will continue
to be counted as long as the ignition is on, even if
another display is being shown on the DIC.
The timer will record up to 99 hours, 59 minutes
and 59 seconds (99:59:59) after which the display
will return to zero.
To stop the timer, press the set/reset button briefly
while TIMER is displayed.
To reset the timer to zero, press and hold the set/reset
button while TIMER is displayed.
Transmission Temperature
Press the trip/fuel button until TRANS TEMP displays.
This display shows the temperature of the automatic
transmission fluid in either degrees Fahrenheit (°F) or
degrees Celsius (°C).
Instantaneous Economy and Active Fuel
Management™Indicator
If your vehicle has this display, press the trip/fuel button
until INST ECON V8 displays. This display shows the
current fuel economy at a particular moment and will
change frequently as driving conditions change. This
display shows the instantaneous fuel economy in miles
per gallon (mpg) or liters per 100 kilometers (L/100 km).
Unlike average economy, this screen cannot be reset.
An Active Fuel Management indicator will display on the
right side of the DIC, while INST ECON displays on the
left side. Active Fuel Management allows the engine to
operate on either four or eight cylinders, depending on
your driving demands. When Active Fuel Management
is active, V4 will display on the DIC. When Active Fuel
Management is inactive, V8 will display. See Active
Fuel Management™
on page 3‑27for more
information.
Blank Display
This display shows no information.
4-54

Transmission Temperature
Press the trip odometer reset stem until TRANS TEMP
displays. This display shows the temperature of the
automatic transmission fluid in either degrees
Fahrenheit (°F) or degrees Celsius (°C).
Trailer Gain and Output
On vehicles with the Integrated Trailer Brake
Control (ITBC) system, the trailer brake display
appears in the DIC. Press the trip odometer reset
stem until TRAILER GAIN and OUTPUT display.
TRAILER GAIN shows the trailer gain setting. This
setting can be adjusted from 0.0 to 10.0 with either a
trailer connected or disconnected. To adjust this setting,
see“Integrated Trailer Brake Control System” under
Towing a Trailer
on page 5‑50for more information.
OUTPUT shows the power output to the trailer anytime
a trailer with electric brakes is connected. Output is
displayed in 0 to 10 bars. Dashes may appear in the
OUTPUT display. See “Integrated Trailer Brake Control
System” underTowing a Trailer
on page 5‑50for
more information.
Compass Zone Setting
This display allows for setting the compass zone.
See DIC Compasson page 4‑62for more information.
Compass Recalibration
This display allows for calibrating the compass.
SeeDIC Compasson page 4‑62for more information.
Oil Life
To access this display, the vehicle must be in P (Park).
Press the trip odometer reset stem until OIL LIFE
REMAINING displays. This display shows an estimate
of the oil's remaining useful life. If you see 99% OIL
LIFE REMAINING on the display, that means 99% of
the current oil life remains. The engine oil life system
will alert you to change the oil on a schedule consistent
with your driving conditions.
When the remaining oil life is low, the CHANGE
ENGINE OIL SOON message will appear on the
display. See “CHANGE ENGINE OIL SOON” underDIC
Warnings and Messages
on page 4‑65. You should
change the oil as soon as you can. See Engine Oilon
page 6‑18. In addition to the engine oil life system
monitoring the oil life, additional maintenance is
recommended in the Maintenance Schedule in this
manual. See Scheduled Maintenance
on page 7‑3for more information.
4-60

vehicle is unloaded. Such a selection when unloaded
may result in unpleasant engine and transmission
driving characteristics and reduced fuel economy.
Tow/Haul is recommended only when pulling a heavy
trailer or a large or heavy load.
Trailer Brakes
A loaded trailer that weighs more than 2,000 lbs
(900 kg) needs to have its own brake system that is
adequate for the weight of the trailer. Be sure to read
and follow the instructions for the trailer brakes so they
are installed, adjusted and maintained properly.
If the vehicle is equipped with StabiliTrak
®, the trailer
cannot tap into the vehicle's hydraulic brake system.
The trailer brake system can tap into the vehicle's
hydraulic brake system only if:
.The trailer parts can withstand 3,000 psi
(20 650 kPa) of pressure.
.The trailer's brake system will use less than
0.02 cubic inch (0.3 cc) of fluid from the vehicle's
master cylinder. Otherwise, both braking systems
will not work well or at all.
If everything checks out this far, make the brake tap at
the port on the master cylinder that sends the fluid to
the rear brakes. Use only steel brake tubing to make
the tap.
Integrated Trailer Brake Control System
The vehicle may have an
Integrated Trailer Brake
Control (ITBC) system for
electric trailer brakes.
This symbol is located on the Trailer Brake Control
Panel on vehicles with an Integrated Trailer Brake
Control System. The power output to the trailer brakes
is based on the amount of brake pressure being applied
by the vehicle’ s brake system. This available power
output to the trailer brakes can be adjusted to a wide
range of trailering situations.
The ITBC system is integrated with the vehicle’s brake,
anti‐lock brake and StabiliTrak (if equipped) systems.
In trailering conditions that cause the vehicle’s anti‐lock
brake or StabiliTrak systems to activate, power sent to
the trailer's brakes will be automatically adjusted to
minimize trailer wheel lock-up. This does not imply that
the trailer has the StabiliTrak system.
5-64

Maintenance When Trailer Towing
The vehicle needs service more often when pulling a
trailer. See this manual's Maintenance Schedule or
Index for more information. Things that are especially
important in trailer operation are automatic transmission
fluid, engine oil, axle lubricant, belts, cooling system
and brake system. It is a good idea to inspect these
before and during the trip.
Check periodically to see that all hitch nuts and bolts
are tight.
Trailer Wiring Harness
The vehicle is equipped with one of the following wiring
harnesses for towing a trailer or hauling a slide-in
camper.
Basic Trailer Wiring
All regular, extended cab and crew cab pickups have a
seven‐wire trailer towing harness.
For vehicles not equipped with heavy duty trailering, the
harness is secured to the vehicle's frame behind the
spare tire mount. The harness requires the installation
of a trailer connector, which is available through your
dealer/retailer.
If towing a light‐duty trailer with a standard four‐way
round pin connector, an adapter is available from your
dealer/retailer.
Heavy-DutyTrailer Wiring Harness
Package
For vehicles equipped with heavy duty trailering, the
harness is connected to a bracket on the hitch platform.
The seven-wire harness contains the following trailer
circuits:
.Yellow: Left Stop/Turn Signal
.Dark Green: Right Stop/Turn Signal
.Brown: Taillamps
.White: Ground
.Light Green: Back-up Lamps
.Red: Battery Feed*
.Dark Blue: Trailer Brake*
5-74

Section 6 Service and Appearance Care
Service. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-4
Accessories and Modifications . . . . . . . . . . . . . . . . . . 6-4
California Proposition 65 Warning . . . . . . . . . . . . . . . 6-5
California Perchlorate Materials Requirements . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-5
Doing Your Own Service Work . . . . . . . . . . . . . . . . . . 6-5
Adding Equipment to the Outside of the Vehicle . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-6
Fuel . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-6
Gasoline Octane . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-7
Gasoline Specifications . . . . . . . . . . . . . . . . . . . . . . . . . 6-7
California Fuel . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-8
Additives . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-8
Fuel E85 (85% Ethanol) . . . . . . . . . . . . . . . . . . . . . . . . . 6-9
Fuels in Foreign Countries . . . . . . . . . . . . . . . . . . . . . 6-11
Filling the Tank . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-11
Filling a Portable Fuel Container . . . . . . . . . . . . . . . 6-13 Checking Things Under the Hood
. . . . . . . . . . . . . . .6-14
Hood Release . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-15
Engine Compartment Overview . . . . . . . . . . . . . . . . 6-16
Engine Oil . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-18
Engine Oil Life System . . . . . . . . . . . . . . . . . . . . . . . . 6-20
Engine Air Cleaner/Filter . . . . . . . . . . . . . . . . . . . . . . . 6-21
Automatic Transmission Fluid (4-Speed Transmission) . . . . . . . . . . . . . . . . . . . . . 6-23
Automatic Transmission Fluid (6-Speed Transmission) . . . . . . . . . . . . . . . . . . . . . 6-26
Cooling System . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-30
Engine Coolant . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-31
Engine Overheating . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-34
Overheated Engine Protection Operating Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-36
Engine Fan Noise . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-37
Power Steering Fluid . . . . . . . . . . . . . . . . . . . . . . . . . . 6-37
Windshield Washer Fluid . . . . . . . . . . . . . . . . . . . . . . 6-38
Brakes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-39
Battery . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-43
Jump Starting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-44
6-1

A.Engine Air Cleaner/Filter on page 6‑21.
B. Coolant Surge Tank and Pressure Cap. See Cooling System on page 6‑30.
C. Positive (+) Terminal. See Jump Starting
on
page 6‑44.
D. Battery on page 6‑43.
E. Engine Oil Fill Cap. See “When to Add Engine Oil”
under Engine Oil on page 6‑18.
F. Automatic Transmission Dipstick. See “Checking
the Fluid Level” underAutomatic Transmission
Fluid (4-Speed Transmission)
on page 6‑23or
Automatic Transmission Fluid (6-Speed
Transmission) on page 6‑26.
G. Remote Negative (−) Terminal (Out of View). See Jump Starting on page 6‑44. H. Engine Oil Dipstick (Out of View). See
“Checking
Engine Oil” underEngine Oil on page 6‑18.
I. Engine Cooling Fan. See Cooling System
on
page 6‑30.
J. Power Steering Fluid Reservoir. See Power
Steering Fluid on page 6‑37.
K. Brake Master Cylinder Reservoir. See “Brake
Fluid” under Brakes on page 6‑39.
L. Underhood Fuse Block on page 6‑122.
M. Windshield Washer Fluid Reservoir. See “Adding
Washer Fluid” underWindshield Washer Fluid
on
page 6‑38.
6-17