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Driving and Operating 279
Parking on Hills
{Warning
To prevent serious injury or death,
always park your vehicle and trailer on a
level surface when possible.
When parking your vehicle and your trailer
on a hill: 1. Press and hold the brake pedal, but do not shift into P (Park). Turn the wheels
toward the curb if facing downhill or
into traffic if facing uphill.
2. Have someone place chocks under the trailer wheels.
3. Gradually release the brake pedal to allow the chocks to absorb the load of
the trailer.
4. Reapply the brake pedal. Then apply the parking brake and shift into P (Park).
5. Release the brake pedal.
Leaving After Parking on a Hill
1. Apply and hold the brake pedal.
.Start the engine.
.Shift into a gear.
.Release the parking brake. 2. Let up on the brake pedal.
3. Drive slowly until the trailer is clear of
the chocks.
4. Stop and have someone pick up and store the chocks.
Launching and Retrieving a Boat
Backing the Trailer into the Water
{Warning
.Have all passengers get out of the
vehicle before backing onto the sloped
part of the ramp. Lower the driver and
passenger side windows before
backing onto the ramp. This will
provide a means of escape in the
unlikely event the vehicle slides into
the water.
.If the boat launch surface is slippery,
have the driver remain in the vehicle
with the brake pedal applied while the
boat is being launched. The boat
launch can be especially slippery at
low tide when part of the ramp was
previously submerged at high tide. Do
not back onto the ramp to launch the
boat if you are not sure the vehicle
can maintain traction.
(Continued)
Warning (Continued)
.Do not move the vehicle if someone is
in the path of the trailer. Some parts
of the trailer might be underwater and
not visible to people who are assisting
in launching the boat.
Disconnect the trailer wiring before backing
the trailer into the water to prevent damage
to the electrical circuits. Reconnect the
wiring to the trailer after removing the
trailer from the water. If the trailer has
electric brakes that can function when the
trailer is submerged, it might help to leave
the electrical trailer connector attached to
maintain trailer brake functionality while on
the boat ramp.
To back the trailer into the water: 1. If equipped, place the vehicle in Four-Wheel Drive High or Automatic
Four-Wheel Drive.
2. Slowly back down the boat ramp until the boat is floating, but no further than
necessary.
3. Press and hold the brake pedal, but do not shift into P (Park).
4. Have someone place chocks under the front wheels of the vehicle.
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280 Driving and Operating
5. Gradually release the brake pedal toallow the chocks to absorb the load of
the trailer.
6. Reapply the brake pedal. Then, apply the parking brake and shift into P (Park).
7. Release the brake pedal.
Pulling the Trailer from the Water
To pull the trailer out of the water: 1. Press and hold the brake pedal.
2. Start the engine and shift into gear.
3. Release the parking brake.
4. Let up on the brake pedal.
5. Drive slowly until the tires are clear of the chocks.
6. Stop and have someone pick up and store the chocks.
7. Slowly pull the trailer from the water.
8. Once the vehicle and trailer have been driven from the sloped part of the boat
ramp, the vehicle can be shifted from
four-wheel-drive high. Shift into the drive
mode that is appropriate for the road
conditions.Caution
If the vehicle tires begin to spin and the
vehicle begins to slide toward the water,
remove your foot from the accelerator
pedal and apply the brake pedal. Seek
help to have the vehicle towed up
the ramp.
Maintenance when Trailer Towing
The vehicle needs service more often when
used to tow trailers. See Maintenance
Schedule 0394. It is especially important to
check the engine oil, axle lubricant, belts,
cooling system, and brake system before
and during each trip.
Check periodically to see that all nuts and
bolts on the trailer hitch are tight.
Engine Cooling When Trailer Towing
The cooling system may temporarily
overheat during severe operating conditions.
See Engine Overheating 0321.
Trailer Towing
If equipped with a diesel engine, see the
Duramax diesel supplement.
Caution
Towing a trailer improperly can damage
the vehicle and result in costly repairs
not covered by the vehicle warranty. To
tow a trailer correctly, follow the
directions in this section and see your
dealer for important information about
towing a trailer with the vehicle.
Trailering is different than just driving the
vehicle by itself. Trailering means changes in
handling, acceleration, braking, and
durability. Successful, safe trailering takes
correct equipment, and it has to be used
properly.
The following information has many
time-tested, important trailering tips and
safety rules. Many of these are important
for your safety and that of your passengers.
Read this section carefully before pulling a
trailer.
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288 Driving and Operating
to the attaching points on the bumper;
otherwise, safety chains should be attached
to holes on the trailer hitch.
Cross the safety chains under the tongue of
the trailer to help prevent the tongue from
contacting the road if it becomes separated
from the hitch. Always leave enough slack in
the safety chains to allow the combination
to turn. Never allow safety chains to drag
on the ground.
Trailer Brakes
Loaded trailers over 900 kg (2,000 lb) must
be equipped with brake systems and with
brakes for each axle. Trailer braking
equipment conforming to Canadian
Standards Association (CSA) requirement
CAN3-D313, or its equivalent, is
recommended.
State or local regulations may require
trailers to have their own braking system if
the loaded weight of the trailer exceeds
certain minimums that can vary from state
to state. Read and follow the instructions for
the trailer brakes so they are installed,
adjusted, and maintained properly. Never
attempt to tap into your vehicle's hydraulicbrake system. If you do, both the vehicle
antilock brakes and the trailer brakes may
not function, which could result in a crash.
Auxiliary Battery
If equipped, the vehicle's auxiliary battery
can be used to supply electrical power to
additional equipment that may be added,
such as a slide-in camper.
Locate the auxiliary battery connector under
the hood on the driver side of the vehicle,
next to the engine compartment fuse block.
Follow the proper installation instructions
included with any electrical equipment that
is installed.
Caution
To prevent draining the auxiliary battery,
always turn off electrical equipment
when not in use and do not use any
equipment that may exceed the
maximum amperage rating of 30 amps.
Trailer Wiring Harness
Basic Trailer Wiring
If the vehicle is not equipped with a trailer
connector on the rear bumper, a seven-wire
trailering harness is tied to the vehiclesframe. The harness requires the installation
of a trailer connector, which is available
through your dealer.
Use only a round, seven-wire connector with
flat blade terminals meeting SAE J2863
specifications for proper electrical
connectivity.
The seven-wire harness contains the
following trailer circuits:
Stop/Turn
Signal Left Yellow/Blue
Stop/Turn Signal
Right Green/Violet
Tail/Parking Lamps Gray/Brown
Reverse Lamps White/Green
Battery Feed Red/Green
Ground White
Electric Trailer Brake Blue
Heavy-Duty Trailer Wiring Harness Package
If equipped, the trailer wiring harness, with
a seven-pin connector and a four-pin
connector, is mounted on the vehicle's rear
bumper.
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290 Driving and Operating
Camper/Fifth-Wheel Trailer Wiring Package
For vehicles without the fifth-wheel/
gooseneck trailer package, the seven-wire
camper harness is under the rear bumper,
attached to the frame near the rear
crossmember. A connector must be added to
the wiring harness that connects to the
camper.
The harness contains the following
camper/trailer circuits:Stop/Turn
Signal Left Yellow/Blue
Stop/Turn Signal
Right Green/Violet
Tail/Parking Lamps Gray/Brown Reverse Lamps White/Green
Battery Feed Red/Green
Ground White
Electric Trailer Brake Blue
If equipped with the heavy-duty trailering
option, see “Heavy-Duty Trailer Wiring
Harness Package” earlier in this section.
When the camper-wiring harness is ordered
without the heavy-duty trailering package, a
seven-wire harness with a seven-pin
connector is at the rear of the vehicle and is
tied to the vehicle's frame.
Trailer Lamps
Always check that all trailer lamps are
working at the beginning of each trip, and
periodically on longer trips.
If equipped, the Trailering App will monitor
the RH turn/brake lamp circuit, LH turn/
brake lamp circuit, running lamp circuit, and
reverse lamp circuits on the trailer. DIC
messages and Trailering App alerts may
display if lighting circuit issues are detected
on the trailer. When a trailer cannot be detected, the
trailer-related DIC messages and/or
Trailering App alerts will not display.
Pressing START LIGHT TEST in the Trailering
App automatically activates trailer lamps.
The Trailering App is not a substitute for
manually inspecting your trailer lamps. See
Trailering App
0296.
Trailer Connection and Lamp Messages
When a trailer is properly connected and
working, no trailer connection or lamp
messages appear on the DIC. However; if
the vehicle detects an issue with a trailer
connection or lamp, you may see the
following DIC message(s):
.TRAILER DISCONNECTED CHECK
CONNECTION appears when a connected
trailer is disconnected. It appears
immediately when the vehicle is on,
or upon the next start-up if the trailer
was disconnected while the vehicle was
off. Check the trailer connection as
appropriate.
.CHECK TRAILER LAMP appears when there
is a detected lamp or wiring fault on the
trailer. Check the trailer wiring and lamps.
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Driving and Operating 291
Turn Signals When Towing a Trailer
When properly connected, the trailer turn
signals will illuminate to indicate the vehicle
is turning, changing lanes, or stopping.
When towing a trailer, the arrows on the
instrument cluster will illuminate even if the
trailer is not properly connected or the bulbs
are burned out.
Tow/Haul Mode
For instructions on how to enter Tow/Haul
Mode, seeDriver Mode Control 0238.
Tow/Haul assists when pulling a heavy
trailer or a large or heavy load. See Tow/
Haul Mode 0227.
Tow/Haul Mode is designed to be most
effective when the vehicle and trailer
combined weight is at least 75% of the
vehicle's Gross Combined Weight Rating
(GCWR). See “Trailer Weight” underTrailer
Towing 0280.
Tow/Haul Mode is most useful when towing
a heavy trailer or carrying a large or
heavy load:
.Through rolling terrain.
.In stop-and-go traffic.
.In busy parking lots. Operating the vehicle in Tow/Haul Mode
when lightly loaded or not towing will not
cause damage; however, it is not
recommended and may result in unpleasant
engine and transmission driving
characteristics, heavy or light steering
efforts, and reduced fuel economy.
Integrated Trailer Brake Control System
The vehicle may have an Integrated Trailer
Brake Control (ITBC) system for use with
electric trailer brakes or most electric over
hydraulic trailer brake systems. These
instructions apply to both types of electric
trailer brakes.
This symbol is on the Trailer Brake Control
Panel on vehicles with an ITBC system. The
power output to the trailer brakes is
proportional to the amount of vehicle
braking. 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, antilock brake, and
StabiliTrak/Electronic Stability Control (ESC)
systems. In trailering conditions that cause
the vehicle’s antilock brake or StabiliTrak/
ESC 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
StabiliTrak/ESC.
If the vehicle’s brake, antilock brake,
or StabiliTrak/ESC systems are not
functioning properly, the ITBC system may
not function fully or at all. Make sure all of
these systems are fully operational to allow
the ITBC system to function properly.
The ITBC system is powered through the
vehicle's electrical system. Turning the
ignition off will also turn off the ITBC
system. The ITBC system is fully functional
only when the ignition is in on.{Warning
Connecting a trailer that has an air brake
system may result in reduced or
complete loss of trailer braking, including
increased stopping distance or trailer
instability which could result in serious
(Continued)
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Vehicle Care 309
Vehicle Care
General Information
General Information . . . . . . . . . . . . . . . . . . . 310
California Perchlorate MaterialsRequirements . . . . . . . . . . . . . . . . . . . . . . . . 310
Accessories and Modifications . . . . . . . . . 310
Vehicle Checks
Doing Your Own Service Work . . . . . . . . . 311
Hood . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 312
Engine Compartment Overview . . . . . . . . 313
Engine Oil . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 314
Engine Oil Life System . . . . . . . . . . . . . . . . . 316
Automatic Transmission Fluid . . . . . . . . . . 317
Engine Air Filter Life System . . . . . . . . . . . 317
Engine Air Cleaner/Filter . . . . . . . . . . . . . . . 318
Cooling System . . . . . . . . . . . . . . . . . . . . . . . . 319
Engine Overheating . . . . . . . . . . . . . . . . . . . . 321
Overheated Engine Protection Operating Mode . . . . . . . . . . . . . . . . . . . . . 323
Engine Fan . . . . . . . . . . . . . . . . . . . . . . . . . . . . 323
Power Steering Fluid . . . . . . . . . . . . . . . . . . 323
Washer Fluid . . . . . . . . . . . . . . . . . . . . . . . . . . 324
Brakes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 325
Brake Pad Life System . . . . . . . . . . . . . . . . . 325
Brake Fluid . . . . . . . . . . . . . . . . . . . . . . . . . . . . 326
Battery - North America . . . . . . . . . . . . . . . 327
Four-Wheel Drive . . . . . . . . . . . . . . . . . . . . . . 329
Front Axle . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 329 Rear Axle . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 329
Noise Control System . . . . . . . . . . . . . . . . . 329
Automatic Transmission Shift Lock
Control Function Check (Mechanical
Shifter) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 330
Park Brake and P (Park) Mechanism Check . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 331
Wiper Blade Replacement . . . . . . . . . . . . . . 331
Glass Replacement . . . . . . . . . . . . . . . . . . . . . 331
Windshield Replacement . . . . . . . . . . . . . . . 332
Gas Strut(s) . . . . . . . . . . . . . . . . . . . . . . . . . . . . 332
Headlamp Aiming
Front Headlamp Aiming . . . . . . . . . . . . . . . 333
Bulb Replacement
Bulb Replacement . . . . . . . . . . . . . . . . . . . . . 333
Halogen Bulbs . . . . . . . . . . . . . . . . . . . . . . . . . 333
LED Lighting . . . . . . . . . . . . . . . . . . . . . . . . . . . 333
Headlamps, Front Turn Signal, Sidemarker, and Parking Lamps . . . . . . 333
Taillamps, Turn Signal, Stoplamps, and Back-Up Lamps . . . . . . . . . . . . . . . . . . . . . . 334
Center High-Mounted Stoplamp (CHMSL) and Cargo Lamp . . . . . . . . . . . . 335
License Plate Lamp . . . . . . . . . . . . . . . . . . . . 335
Electrical System
Electrical System Overload . . . . . . . . . . . . . 335
Fuses and Circuit Breakers . . . . . . . . . . . . . 337
Engine Compartment Fuse Block . . . . . . . 337 Instrument Panel Fuse Block (Left) . . . . . 341
Instrument Panel Fuse Block (Right) . . . 342
Wheels and Tires
Tires . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 345
All-Season Tires . . . . . . . . . . . . . . . . . . . . . . . . 345
Winter Tires . . . . . . . . . . . . . . . . . . . . . . . . . . . 346
All-Terrain Tires . . . . . . . . . . . . . . . . . . . . . . . 346
Tire Sidewall Labeling . . . . . . . . . . . . . . . . . 346
Tire Designations . . . . . . . . . . . . . . . . . . . . . . 347
Tire Terminology and Definitions . . . . . . 348
Tire Pressure . . . . . . . . . . . . . . . . . . . . . . . . . . 350
Tire Pressure Monitor System . . . . . . . . . . 351
Tire Pressure Monitor Operation . . . . . . . 351
Tire Inspection . . . . . . . . . . . . . . . . . . . . . . . . 356
Tire Rotation . . . . . . . . . . . . . . . . . . . . . . . . . . 357
When It Is Time for New Tires . . . . . . . . 359
Buying New Tires . . . . . . . . . . . . . . . . . . . . . 360
Different Size Tires and Wheels . . . . . . . . 361
Uniform Tire Quality Grading . . . . . . . . . . 361
Wheel Alignment and Tire Balance . . . . 362
Wheel Replacement . . . . . . . . . . . . . . . . . . . 362
Tire Chains . . . . . . . . . . . . . . . . . . . . . . . . . . . . 363
If a Tire Goes Flat . . . . . . . . . . . . . . . . . . . . . 364
Tire Changing . . . . . . . . . . . . . . . . . . . . . . . . . 365
Full-Size Spare Tire . . . . . . . . . . . . . . . . . . . . . 375
Jump Starting
Jump Starting - North America . . . . . . . . 376
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330 Vehicle Care
General Motors LLC, and is not limited to
any particular part, component or system of
the vehicle manufactured by General Motors
LLC. Defects in design, assembly or in any
part, component or system of the vehicle as
manufactured by General Motors LLC, which,
at the time it left General Motors LLC’s
control, caused noise emissions to exceed
Federal standards, are covered by this
warranty for the life of the vehicle.
TAMPERING WITH NOISE CONTROL
SYSTEM PROHIBITED
Federal law prohibits the following acts or
the causing thereof:1. The removal or rendering inoperative by any person, other than for purposes of
maintenance, repair, or replacement, of
any device or element of design
incorporated into any new vehicle for
the purpose of noise control prior to its
sale or delivery to the ultimate purchaser
or while it is in use; or
2. the use of the vehicle after such device or element of design has been removed
or rendered inoperative by any person. Among those acts presumed to constitute
tampering are the acts listed below.
Insulation:
Removal of the noise shields or any
undercab insulation.
Engine:
Removal or rendering engine speed
governor, if so equipped, inoperative so as
to allow engine speed to exceed
manufacturer specifications.
Modification of the engine control system or
calibration.
Fan and Drive:
.Removal of fan clutch or rendering clutch
inoperative.
.Removal of the fan shroud.
Air Intake:
.Removal of air cleaner silencer.
.Reversing air cleaner cover.
Exhaust:
.Removal of muffler, catalytic converter,
and/or resonator.
.Removal of exhaust pipes and exhaust
pipe clamps.
Automatic Transmission Shift Lock
Control Function Check
(Mechanical Shifter)
{Warning
When you are doing this inspection, the
vehicle could move suddenly. If the
vehicle moves, you or others could be
injured.
1. Before starting this check, be sure there is enough room around the vehicle.
It should be parked on a level surface.
2. Apply the parking brake. Be ready to apply the regular brake immediately if
the vehicle begins to move.
3. With the engine off, turn the ignition on, but do not start the engine. Without
applying the regular brake, try to move
the shift lever out of P (Park) with
normal effort. If the shift lever moves
out of P (Park), contact your dealer for
service.
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Vehicle Care 331
Park Brake and P (Park)
Mechanism Check
{Warning
When you are doing this check, the
vehicle could begin to move. You or
others could be injured and property
could be damaged. Make sure there is
room in front of the vehicle in case it
begins to roll. Be ready to apply the
regular brake at once should the vehicle
begin to move.
Park on a fairly steep hill, with the vehicle
facing downhill. Keeping your foot on the
regular brake, set the parking brake.
.To check the parking brake's holding
ability: With the engine running and the
transmission in N (Neutral), slowly remove
foot pressure from the regular brake
pedal. Do this until the vehicle is held by
the parking brake only.
.To check the P (Park) mechanism's holding
ability: With the engine running, shift to
P (Park). Then release the parking brake
followed by the regular brake.
Contact your dealer if service is required.
Wiper Blade Replacement
Windshield wiper blades should be replaced
periodically. See Maintenance Schedule
0 394.
Replacement blades come in different types
and are removed in different ways. For
proper type and length, see Maintenance
Replacement Parts 0399.
Caution
Allowing the wiper arm to touch the
windshield when no wiper blade is
installed could damage the windshield.
Any damage that occurs would not be
covered by the vehicle warranty. Do not
allow the wiper arm to touch the
windshield.
Front Wiper Blade Replacement
To replace the wiper blade:
1. Pull the wiper assembly away from the windshield.
2. Lift up on the latch in the middle of the
wiper blade where the wiper arm
attaches.
3. With the latch open, pull the wiper blade down toward the windshield far enough
to release it from the J-hooked end of
the wiper arm.
4. Remove the wiper blade.
5. Reverse Steps 1–3 for wiper blade replacement.
Glass Replacement
If the windshield or front side glass must be
replaced, see your dealer to determine the
correct replacement glass.