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Driving and Operating 225
ignition is on, but the vehicle will not
be able to be driven. The engine will not
start in Service Mode. Press the ENGINE
START/STOP button again to turn the
ignition off.
Starting the Engine
If the vehicle has a diesel engine, see the
Duramax diesel supplement.
Caution
If you add electrical parts or accessories,
you could change the way the engine
operates. Any resulting damage would
not be covered by the vehicle warranty.
SeeAdd-On Electrical Equipment 0297.
Move the shift lever to P (Park) or
N (Neutral). To restart the engine when the
vehicle is already moving, use
N (Neutral) only.
Caution
Do not try to shift to P (Park) if the
vehicle is moving. If you do, you could
damage the transmission. Shift to P (Park)
only when the vehicle is stopped.
Starting Procedure
1. For Key Access vehicles, turn the ignition key to Start. When the engine starts, let
go of the key. For Keyless Access
vehicles, the remote key must be in the
vehicle. Press ENGINE START/STOP with
the brake pedal applied. When the
engine begins cranking, let go of the
button.
The driver may observe a minor, and
temporary, brake pedal kickback when
starting the vehicle. This is normal.
The idle speed will go down as the
engine gets warm. Do not race the
engine immediately after starting it.
Operate the engine and transmission
gently to allow the oil to warm up and
lubricate all moving parts.
When the low fuel warning light is on
and the FUEL LEVEL LOW message is
displayed in the Driver Information
Center (DIC), hold the ignition switch in
the START position to continue engine
cranking.Caution
Cranking the engine for long periods of
time, by returning the ignition to the
START position immediately after
cranking has ended, can overheat and
damage the cranking motor, and drain
the battery. Wait at least 15 seconds
between each try, to let the cranking
motor cool down.
2. If the engine does not start after five to 10 seconds, especially in very cold
weather (below −18 °C or 0 °F), it could
be flooded with too much gasoline. Try
pushing the accelerator pedal all the way
to the floor and holding it there while
holding the key in START or ENGINE
START/STOP for up to a maximum of
15 seconds. Wait at least 15 seconds
between each try, to allow the cranking
motor to cool down. When the engine
starts, let go of the key or button and
accelerator. If the vehicle starts briefly
but then stops again, do the same thing.
This clears the extra gasoline from the
engine. Do not race the engine
immediately after starting it. Operate
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226 Driving and Operating
the engine and transmission gently until
the oil warms up and lubricates all
moving parts.
Engine Heater
If equipped, the engine heater can provide
easier starting and better fuel economy
during engine warm-up in cold weather
conditions at or below−18 °C (0 °F). Vehicles
with an engine heater should be plugged in
at least four hours before starting. An
internal thermostat in the plug-end of the
cord may exist, which will prevent engine
heater operation at temperatures above
−18 °C (0 °F).
{Warning
Do not plug in the engine block heater
while the vehicle is parked in a garage or
under a carport. Property damage or
personal injury may result. Always park
the vehicle in a clear open area away
from buildings or structures.
To Use the Engine Heater
1. Turn off the engine.
2. Check the heater cord for damage. If it is damaged, do not use it. See your dealer
for a replacement. Inspect the cord for
damage yearly.
3. Plug the heater cord into the connector in the front fascia.
4. Plug the cord into a grounded 110-volt AC outlet that is protected by a ground
fault detection function.
{Warning
Improper use of the heater cord or an
extension cord can damage the cord and
may result in overheating and fire.
.Plug the cord into a three-prong
electrical utility receptacle that is
protected by a ground fault detection
function. An ungrounded outlet could
cause an electric shock.
.Use a weatherproof, heavy-duty,
15 amp-rated extension cord if needed.
Failure to use the recommended
extension cord in good operating
condition, or using a damaged heater
or extension cord, could make it
overheat and cause a fire, property
damage, electric shock, and injury.
.Do not operate the vehicle with the
heater cord permanently attached to
the vehicle. Possible heater cord and
thermostat damage could occur.
.While in use, do not let the heater
cord touch vehicle parts or sharp
edges. Never close the hood on the
heater cord.
(Continued)
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Driving and Operating 269
.Become familiar with, and follow all state
and local laws that apply to trailer
towing. These requirements vary from
state to state.
.State laws may require the use of
extended side view mirrors. If your
visibility is limited or restricted while
towing, install extended side view mirrors
on your vehicle, even if not required.
.Do not tow a trailer during the first
800 km (500 mi) of vehicle use to prevent
damage to the engine, axle, or other
parts.
.Perform the first oil change before heavy
towing.
.Do not drive over 800 km/h (50 mph) and
do not make starts at full throttle during
the first 800 km (500 mi) of trailer
towing.
.Tow in D (Drive). Tow/Haul Mode is
recommended for heavier trailers. See
Tow/Haul Mode0234. If the transmission
downshifts too often, a lower gear may
be selected using Manual Mode. See
Manual Mode 0232.
If equipped, the following driver assistance
features should be turned off when towing
a trailer:
.Park Assist
.Automatic Parking Assist (APA)
.Reverse Automatic Braking (RAB)
If equipped, the following driver assistance
features should be turned to alert or off
when towing a trailer, unless equipped with
Super Cruise:
.Automatic Emergency Braking (AEB)
.Front Pedestrian Braking (FPB)
If equipped with Lane Change Alert (LCA),
the LCA detection zones that extend back
from the side of the vehicle do not move
further back when a trailer is towed. Use
caution while changing lanes when towing a
trailer.
If equipped with Rear Cross Traffic Alert
(RCTA), use caution while backing up when
towing a trailer, as the RCTA detection zones
that extend out from the back of the vehicle
do not move further back when a trailer is
towed.
{Warning
To prevent serious injury or death from
carbon monoxide (CO), when towing a
trailer: (Continued)
Warning (Continued)
.Do not drive with the liftgate, trunk/
hatch, or rear-most window open.
.Fully open the air outlets on or under
the instrument panel.
.Adjust the climate control system to a
setting that brings in only outside air.
See“Climate Control Systems” in the
Index.
For more information about carbon
monoxide, see Engine Exhaust 0229.
Towing a trailer requires experience. The
combination of the vehicle and trailer is
longer and not as responsive as the vehicle
itself. Get used to the handling and braking
of the combination by driving on a level
road surface before driving on public roads.
The trailer structure, the tires, and the
brakes must all be rated to carry the
intended cargo. Inadequate trailer
equipment can cause the combination to
operate in an unexpected or unsafe manner.
Before driving, inspect all trailer hitch parts
and attachments, safety chains, electrical
connectors, lamps, tires, and mirrors. See
Towing Equipment 0276. If the trailer has
electric brakes, start the combination
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270 Driving and Operating
moving and then manually apply the trailer
brake controller to check that the trailer
brakes work. During the trip, occasionally
check that the cargo and trailer are secure
and that the lamps and any trailer brakes
are working.
Towing with a Stability Control System
When towing, the stability control system
might be heard. The system reacts to
vehicle movement caused by the trailer,
which mainly occurs during cornering. This is
normal when towing heavier trailers.
Following Distance
Stay at least twice as far behind the vehicle
ahead as you would when driving without a
trailer. This can help to avoid heavy braking
and sudden turns.
Passing
More passing distance is needed when
towing a trailer. The combination of the
vehicle and trailer will not accelerate as
quickly and is much longer than the vehicle
alone. It is necessary to go much farther
beyond the passed vehicle before returning
to the lane. Pass on level roadways. Avoid
passing on hills if possible.
Backing Up
Hold the bottom of the steering wheel with
one hand. To move the trailer to the left,
move that hand to the left. To move the
trailer to the right, move that hand to the
right. Always back up slowly and, if possible,
have someone guide you.
Making TurnsCaution
Turn more slowly and make wider arcs
when towing a trailer to prevent damage
to your vehicle. Making very sharp turns
could cause the trailer to contact the
vehicle.
Make wider turns than normal when towing,
so the trailer will not go over soft shoulders,
over curbs, or strike road signs, trees,
or other objects. Always signal turns well in
advance. Do not steer or brake suddenly.
Driving on Grades
Reduce speed and shift to a lower gear
before starting down a long or steep
downhill grade. If the transmission is not
shifted down, the brakes may overheat and
result in reduced braking efficiency. The vehicle can tow in D (Drive). Shift the
transmission to a lower gear if the
transmission shifts too often under heavy
loads and/or hilly conditions.
When towing at higher altitudes, engine
coolant will boil at a lower temperature
than at lower altitudes. If the engine is
turned off immediately after towing at high
altitude on steep uphill grades, the vehicle
could show signs similar to engine
overheating. To avoid this, let the engine
run, preferably on level ground, with the
transmission in P (Park) for a few minutes
before turning the engine off. If the
overheat warning comes on, see
Engine
Overheating 0313.
Viewing Systems
If equipped, the viewing systems on the
vehicle can improve visibility while hitching,
backing, and driving with a trailer. See
Driver Assistance Systems 0246.
Parking on Hills
{Warning
To prevent serious injury or death,
always park your vehicle and trailer on a
level surface when possible.
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Vehicle Care 301
Vehicle Care
General Information
General Information . . . . . . . . . . . . . . . . . . . 302
California Perchlorate MaterialsRequirements . . . . . . . . . . . . . . . . . . . . . . . . 302
Accessories and Modifications . . . . . . . . . 302
Vehicle Checks
Doing Your Own Service Work . . . . . . . . 303
Hood . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 303
Engine Compartment Overview . . . . . . . . 305
Engine Oil . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 306
Engine Oil Life System . . . . . . . . . . . . . . . . 308
Automatic Transmission Fluid . . . . . . . . . 309
Engine Air Filter Life System . . . . . . . . . . 309
Engine Air Cleaner/Filter . . . . . . . . . . . . . . . 310
Cooling System . . . . . . . . . . . . . . . . . . . . . . . . 311
Engine Overheating . . . . . . . . . . . . . . . . . . . . 313
Overheated Engine Protection Operating Mode . . . . . . . . . . . . . . . . . . . . . 315
Engine Fan . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 315
Power Steering Fluid . . . . . . . . . . . . . . . . . . . 315
Washer Fluid . . . . . . . . . . . . . . . . . . . . . . . . . . 316
Brakes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 317
Brake Pad Life System . . . . . . . . . . . . . . . . . 317
Brake Fluid . . . . . . . . . . . . . . . . . . . . . . . . . . . . 318
Battery - North America . . . . . . . . . . . . . . . 319
Four-Wheel Drive . . . . . . . . . . . . . . . . . . . . . . 321
Front Axle . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 321 Rear Axle . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 321
Noise Control System . . . . . . . . . . . . . . . . . . 321
Automatic Transmission Shift Lock
Control Function Check (Mechanical
Shifter) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 322
Park Brake and P (Park) Mechanism Check . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 323
Wiper Blade Replacement . . . . . . . . . . . . . 323
Glass Replacement . . . . . . . . . . . . . . . . . . . . . 323
Windshield Replacement . . . . . . . . . . . . . . 324
Gas Strut(s) . . . . . . . . . . . . . . . . . . . . . . . . . . . 324
Headlamp Aiming
Front Headlamp Aiming . . . . . . . . . . . . . . . 325
Bulb Replacement
Bulb Replacement . . . . . . . . . . . . . . . . . . . . . 325
Halogen Bulbs . . . . . . . . . . . . . . . . . . . . . . . . . 325
LED Lighting . . . . . . . . . . . . . . . . . . . . . . . . . . . 325
Headlamps, Front Turn Signal, Sidemarker, and Parking Lamps . . . . . . 325
Taillamps, Turn Signal, Stoplamps, and Back-Up Lamps . . . . . . . . . . . . . . . . . . . . . . 326
Center High-Mounted Stoplamp (CHMSL) and Cargo Lamp . . . . . . . . . . . . 327
License Plate Lamp . . . . . . . . . . . . . . . . . . . . 327
Electrical System
Electrical System Overload . . . . . . . . . . . . . 327
Fuses and Circuit Breakers . . . . . . . . . . . . . 329
Engine Compartment Fuse Block . . . . . . 329 Instrument Panel Fuse Block (Left) . . . . . 333
Instrument Panel Fuse Block (Right) . . . 334
Wheels and Tires
Tires . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 337
All-Season Tires . . . . . . . . . . . . . . . . . . . . . . . . 338
Winter Tires . . . . . . . . . . . . . . . . . . . . . . . . . . . 338
All-Terrain Tires . . . . . . . . . . . . . . . . . . . . . . . . 338
Tire Sidewall Labeling . . . . . . . . . . . . . . . . . 338
Tire Designations . . . . . . . . . . . . . . . . . . . . . . 339
Tire Terminology and Definitions . . . . . 340
Tire Pressure . . . . . . . . . . . . . . . . . . . . . . . . . . 342
Tire Pressure Monitor System . . . . . . . . . 343
Tire Pressure Monitor Operation . . . . . . 344
Tire Inspection . . . . . . . . . . . . . . . . . . . . . . . . 348
Tire Rotation . . . . . . . . . . . . . . . . . . . . . . . . . . 349
When It Is Time for New Tires . . . . . . . . . 351
Buying New Tires . . . . . . . . . . . . . . . . . . . . . . 352
Different Size Tires and Wheels . . . . . . . . 353
Uniform Tire Quality Grading . . . . . . . . . . 353
Wheel Alignment and Tire Balance . . . . 354
Wheel Replacement . . . . . . . . . . . . . . . . . . . 354
Tire Chains . . . . . . . . . . . . . . . . . . . . . . . . . . . . 355
If a Tire Goes Flat . . . . . . . . . . . . . . . . . . . . . 356
Tire Changing . . . . . . . . . . . . . . . . . . . . . . . . . . 357
Full-Size Spare Tire . . . . . . . . . . . . . . . . . . . . 367
Jump Starting
Jump Starting - North America . . . . . . . . 367
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Vehicle Care 309
The oil life system can also be reset as
follows:1. Display the oil life percentage on the DIC. See Driver Information Center (DIC)
(Base Level) 0128 or
Driver Information Center (DIC) (Midlevel
and Uplevel) 0130.
2. Fully press the accelerator pedal slowly three times within five seconds.
3. If the display changes to 100%, the system is reset.
If the vehicle has a CHANGE ENGINE OIL
SOON message and it comes back on when
the vehicle is started and/or the oil
life percentage is near 0%, the engine oil
life system has not been reset. Repeat the
procedure.
Automatic Transmission Fluid
When to Check and Change Automatic
Transmission Fluid
It is usually not necessary to check the
transmission fluid level. The only reason for
fluid loss is a transmission leak or
overheated transmission. This vehicle is not
equipped with a transmission fluid level
dipstick. There is a special procedure for
checking and changing the transmission fluid in these vehicles. Because this procedure is
difficult, this should be done at the dealer.
Contact the dealer for additional information
or the procedure can be found in the service
manual. See
Publication Ordering
Information 0404.
Caution
Use of the incorrect automatic
transmission fluid may damage the
vehicle, and the damage may not be
covered by the vehicle warranty. Always
use the correct automatic transmission
fluid. See Recommended Fluids and
Lubricants 0389.
Change the fluid and filter at the scheduled
maintenance intervals listed in Maintenance
Schedule 0385. Be sure to use the
transmission fluid listed in Recommended
Fluids and Lubricants 0389.
Engine Air Filter Life System
This feature provides the engine air filter’s
remaining life and best timing for a change.
The timing to change and engine air filter
depends on driving and environmental
conditions.
When to Change Engine Air Filter
When the Driver Information Center (DIC)
displays a message to replace the engine air
filter at the next oil change, follow this
timing.
When the DIC displays a message to replace
the engine air filter soon, replace the engine
air filter at the earliest convenience.
The system must be reset after the engine
air filter is changed.
If the DIC displays a message to check the
engine air filter system, see your dealer.
How to Reset Engine Air Filter Life
System
To reset:
1. Place the vehicle in P (Park).
2. Display the Air Filter Life on the DIC. See Driver Information Center (DIC) (Base
Level) 0128 or
Driver Information Center (DIC) (Midlevel
and Uplevel) 0130.
3. Press
Ton the steering wheel, or press
the trip odometer reset stem if the
vehicle does not have the DIC controls,
to move to the Reset/Disable display
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Vehicle Care 315
normal idle speed for at least five minutes
while the vehicle is parked. If the warning is
still there, turn off the engine and get
everyone out of the vehicle until it
cools down.
If there is no sign of steam, idle the engine
for five minutes while parked. If the warning
is still displayed, turn off the engine until it
cools down.
Overheated Engine Protection
Operating Mode
If an overheated engine condition exists and
the ENGINE POWER IS REDUCED message
displays, an overheat protection mode which
alternates firing groups of cylinders helps to
prevent engine damage. In this mode, a loss
in power and engine performance will be
noticed. This operating mode allows the
vehicle to be driven to a safe place in an
emergency. Driving extended distances and/
or towing a trailer in the overheat
protection mode should be avoided.
If the engine or transmission detects an
impending hot fluid condition, then the
transmission may force upshifts to limit
temperatures. Downshifts may also be
prevented in this instance. Normal operationmay continue unless the display indicates
there is a hot condition and engine should
be idled.
Caution
After driving in the overheated engine
protection operating mode, the engine oil
will be severely degraded. Any repairs
performed before the engine is cool may
cause engine damage. Allow the engine
to cool before attempting any repair.
Repair the cause of coolant loss, change
the oil, and reset the oil life system. See
Engine Oil
0306.
Engine Fan
If the vehicle has the Duramax diesel
engine, see the Duramax diesel supplement.
The vehicle has a clutched engine cooling
fan. When the clutch is engaged, the fan
spins faster to provide more air to cool the
engine. In most everyday driving conditions,
the fan is spinning slower and the clutch is
not fully engaged. This improves fuel
economy and reduces fan noise. Under
heavy vehicle loading, trailer towing, and/or
high outside temperatures, the fan speed
increases as the clutch more fully engages, so an increase in fan noise may be heard.
This is normal and should not be mistaken
as the transmission slipping or making extra
shifts. It is merely the cooling system
functioning properly. The fan will slow down
when additional cooling is not required and
the clutch partially disengages.
This fan noise may be heard when starting
the engine. It will go away as the fan clutch
partially disengages.
Power Steering Fluid
The power steering fluid reservoir is in the
engine compartment on the driver side of
the vehicle. See
Engine Compartment
Overview 0305 for reservoir location.
When to Check Power Steering Fluid
It is not necessary to regularly check power
steering fluid unless there is a leak
suspected in the system or an unusual noise
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Service and Maintenance 387
* Footnote: Under extreme driving
conditions listed above, it may be
necessary to replace your spark plugs at
more frequent intervals. For further
assistance in determining the most
suitable service maintenance intervals for
your vehicle, please contact your
authorized GM Dealer.
Extreme service is for vehicles mainly
driven off-road in four-wheel drive or used
in farming, mining, forestry, or snow
plowing.
Additional Required Services—Severe
Service
Every 40 000 km (25,000 mi)
.Change transfer case fluid, if equipped
with 4WD. Do not directly power wash
the transfer case and/or front/rear axle
output seals. High pressure water can
overcome the seals and contaminate the
transfer case fluid. Contaminated fluid will
decrease the life of the transfer case and/
or axles and should be replaced. Every 72 000 km (45,000 mi)
.Change automatic transmission fluid and
filter.
Owner Checks and Services
Every Five Years
.Replace brake fluid.
Every Seven Years
.Replace Air Conditioning Desiccant every
seven years. The air conditioning system
requires maintenance every seven years.
This service requires replacement of the
desiccant to help the longevity and
efficient operation of the air conditioning
system. This service can be complex. See
your dealer.
Multi-Point Vehicle
Inspection (MPVI)
A Multi Point Vehicle Inspection (MPVI)
completed by a GM dealer technician is a
maintenance assessment of your vehicle.
The benefit of the MPVI is to identify and
inform the customer of service items that
require immediate attention and those that
may require attention in the future. The technician will perform the following
checks on your vehicle. For a complete list
of checks, inspections, and services, see your
dealer.
Some items may not apply to your vehicle
and/or region.
Diagnostics
.OnStar active, if equipped
.Service history/recall check
Engine Oil and Filter
.Engine oil
.Oil life monitor
‐
Reset oil life monitor
Exterior Lights
.Visual inspection
Windshield and Wipers
.Visual inspection
Battery
.Battery visual inspection
.Battery test results
.Battery cables and connections