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warned of vehicles rapidly approaching this
area up to approximately 70 m (230 ft)
behind the vehicle.
Trailer Side Blind Zone Area (TSBZA)
If equipped, the TSBZA system is a
lane-changing aid that assists drivers with
avoiding crashes that occur with moving
vehicles in the side blind zone, or blind spot
areas. The trailer side blind zone area adds
the blind zone area along the side of a
trailer that the host vehicle is pulling.
When the vehicle is in a forward gear, the
left or right side mirror display will light up
if a moving vehicle is detected in that trailer
blind zone. If the turn signal is activated and
a vehicle is also detected on the same side,
the display will flash as an extra warning
not to change lanes. Since this system is
part of the Lane Change Alert system, read
the entire Lane Change Alert section before
using this feature.
{Warning
TSBZA does not alert the driver to
vehicles outside of the system detection
zones, pedestrians, bicyclists, or animals.
It may not provide alerts when changing(Continued)
Warning (Continued)
lanes under all driving conditions. Failure
to use proper care when changing lanes
may result in injury, death, or vehicle
damage. Before making a lane change,
always check mirrors, glance over your
shoulder, and use the turn signals.
TSBZA Detection Zones
1. SBZA Detection Zone
2. TSBZA Detection Zone
3. LCA Detection Zone
The Side Blind Zone Alert (SBZA) warning
area starts at approximately the middle of
the vehicle and goes back 5 m (16 ft). The
Trailer Side Blind Zone Alert (TSBZA) warning
area starts at approximately 3 m (10 ft) to
the trailing edge of the vehicle and goes
back up to 21 m (69 ft) behind the vehicle.
The maximum trailer length is 18 m (59 ft).
How the System Works
The LCA/TSBZA symbol lights up in the side
mirrors when the system detects a moving
vehicle in the next lane over that is in the
trailer side blind zone. This indicates it may
be unsafe to change lanes. Before making a
lane change, check the SBZA display, check
mirrors, glance over your shoulder, and use
the turn signals.
Left Side Mirror DisplayRight Side Mirror Display
When the vehicle is started, both outside
mirror LCA/TSBZA displays will briefly come
on to indicate the system is operating.
When the vehicle is in a forward gear, the
left- or right-side mirror display will light up
if a moving vehicle is detected in that blind
zone. If the turn signal is activated in the
same direction as a detected vehicle, this
display will flash as an extra warning not to
change lanes.

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270 Driving and Operating
LCA/TSBZA displays may not come on when
passing a vehicle quickly, or when passing a
stopped vehicle. LCA/TSBZA may alert to
objects attached to the vehicle, such as a
bicycle, or object extending out to either
side of the vehicle or trailer. This is normal
system operation; the vehicle does not need
service.
LCA/TSBZA can be disabled through vehicle
settings. To view available settings from the
infotainment screen, touch Settings >
Vehicle > Collision/Detection Systems.
If SBZA is disabled by the driver, the TSBZA
mirror displays will not light up.
When the System Does Not Seem to
Work Properly
LCA/TSBZA displays may not come on when
passing a vehicle quickly, or when passing a
stopped vehicle. The LCA/TSBZA 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. LCA/TSBZA may
alert to objects attached to the vehicle, such
as a trailer, bicycle, or object extending out
to either side of the vehicle or trailer. This is
normal system operation; the vehicle does
not need service.LCA/TSBZA may not always alert the driver
to vehicles in the side blind zone, especially
in wet conditions. The system does not need
to be serviced. The system may light up due
to guardrails, signs, trees, shrubs, and other
non-moving objects. This is normal system
operation; the vehicle does not need service.
LCA/TSBZA may not operate when the
LCA/TSBZA sensors in the left or right
corners of the rear bumper are covered with
mud, dirt, snow, ice, or slush, or in heavy
rainstorms. For cleaning instructions, see
"Washing the Vehicle" under
Exterior Care
0 383. If the DIC displays the system
unavailable message after cleaning both
sides of the vehicle toward the rear corners
of the vehicle, see your dealer.
If the DIC displays the system unavailable
message after cleaning both sides of the
vehicle toward the rear corners of the
vehicle, see your dealer
If the LCA/TSBZA displays do not light up
when vehicles are in the blind zone and the
system is clean, the system may need
service. Take the vehicle to your dealer. When TSBZA is disabled for any reason
other than the driver turning it off, the
Trailer Side Blind Zone Alert On option will
not be available on the
personalization menu.
Driving with a Trailer
Although this system is intended to help
drivers avoid lane change crashes, it does
not replace driver vision and therefore
should be considered a lane change aid.
Even with the TSBZA system, the driver
must check carefully for objects outside of
the reporting zone (e.g., a fast approaching
vehicle) or vehicle along the side of the
trailer before changing lanes.
Use caution while changing lanes when
towing a trailer.
Lane Departure Warning (LDW)
If equipped, LDW may help avoid crashes
due to unintentional lane departures. LDW
uses a camera sensor to detect the lane
markings at speeds of 56 km/h (35 mph) or
greater. It may provide an alert if the
vehicle is crossing a lane without using a
turn signal in that direction. LDW light will
not alert if the turn signal is active in the

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Driving and Operating 271
direction of lane departure, or if LDW
detects that you are accelerating, braking or
actively steering.
{Warning
The LDW system does not steer the
vehicle. The LDW system may not:
.Provide enough time to avoid a crash.
.Detect lane markings under poor
weather or visibility conditions. This
can occur if the windshield or
headlamps are blocked by dirt, snow,
or ice; if they are not in proper
condition; or if the sun shines directly
into the camera.
.Detect road edges.
.Detect lanes on winding or hilly roads.
If LDW only detects lane markings on one
side of the road, it will only warn you
when departing the lane on the side
where it has detected a lane marking.
Always keep your attention on the road
and maintain proper vehicle position
within the lane, or vehicle damage,
injury, or death could occur. Always keep (Continued)
Warning (Continued)
the windshield, headlamps, and camera
sensors clean and in good repair. Do not
use LDW in bad weather conditions.
How the System Works
LDW utilizes a camera sensor installed on
the windshield ahead of the rearview mirror
to detect lane markings.
To turn LDW on and off, press
@on the
center stack. The control indicator will light
when LDW is on.
BaseUplevel
When LDW is on,
@ornis green if
LDW is available to warn of a lane
departure. If the vehicle crosses a detected
lane marking without using the turn signal
in that direction,
@ornchanges to
amber and flashes. Additionally, there will
be three beeps, on the right or left, depending on the lane departure direction.
LDW will not alert if the turn signal is active
in the direction of lane departure or if LDW
detects that you are accelerating, braking or
actively steering.
Fuel
Top Tier Fuel
GM recommends the use of TOP TIER
Detergent Gasoline to keep the engine clean,
reduce engine deposits, and maintain
optimal vehicle performance. Look for the
TOP TIER Logo or see www.toptiergas.com
for a list of TOP TIER Detergent Gasoline
marketers and applicable countries.

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Driving and Operating 273
The use of E85 or FlexFuel is encouraged
when the vehicle is designed to use it. E85
or FlexFuel is made from renewable sources.
To help locate fuel stations that carry E85 or
FlexFuel, the U.S. Department of Energy has
an alternative fuel website. See
www.afdc.energy.gov/afdc/locator/stations.
E85 or FlexFuel should meet ASTM
Specification D 5798 or CAN/CGSB–3.512 in
Canada. Do not use the fuel if the ethanol
content is greater than 85%. Fuel mixtures
that do not meet ASTM or CGSB
specifications can affect driveability and
could cause the malfunction indicator lamp
to come on.
The starting characteristics of E85 or FlexFuel
make it unsuitable for use when
temperatures fall below−18 °C (0 °F). Use
gasoline or add gasoline to the E85 or
FlexFuel.
Because E85 or FlexFuel has less energy per
liter (gallon) than gasoline, the vehicle will
need to be refilled more often. See Filling
the Tank (Chassis Cab and Box Delete
Models) 0275 or
Filling the Tank (Pickup Models) 0273. The only GM approved aftermarket additive
is ACDelco Fuel System Treatment
Plus-FlexFuel. Follow the instructions on the
bottle for proper use. This product is
available at your GM dealer.
Caution
Some additives are not compatible with
E85 or FlexFuel and can harm the
vehicle's fuel system. Use only additives
approved by GM for E85 or FlexFuel
vehicles. Damage caused by unapproved
additives would not be covered by the
vehicle warranty.
Caution
Do not use fuel containing methanol.
It can corrode metal parts in the fuel
system and also damage plastic and
rubber parts. That damage would not be
covered under the vehicle warranty.
To help keep the engine running efficiently,
fill the tank with gasoline, up to E15, after
filling the tank with E85 one or two times.
Filling the Tank (Pickup Models)
If the vehicle has a diesel engine, see the
Duramax diesel supplement.
An arrow on the fuel gauge indicates which
side of the vehicle the fuel door is on. See
Fuel Gauge 0116.
{Warning
Fuel vapors and fuel fires burn violently
and can cause injury or death.
Follow these guidelines to help avoid
injuries to you and others:
.Read and follow all the instructions on
the fuel pump island.
.Turn off the engine when refueling.
.Keep sparks, flames, and smoking
materials away from fuel.
.Do not leave the fuel pump
unattended.
.Avoid using electronic devices while
refueling.
.Do not re-enter the vehicle while
pumping fuel.
(Continued)

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Driving and Operating 275
Filling the Tank (Chassis Cab and
Box Delete Models)
If the vehicle has a diesel engine, see the
Duramax diesel supplement.
An arrow on the fuel gauge indicates which
side of the vehicle the fuel fill is on. See
Fuel Gauge0116.
{Warning
Fuel vapors and fuel fires burn violently
and can cause injury or death.
Follow these guidelines to help avoid
injuries to you and others:
.Read and follow all the instructions on
the fuel pump island.
.Turn off the engine when refueling.
.Keep sparks, flames, and smoking
materials away from fuel.
.Do not leave the fuel pump
unattended.
.Avoid using electronic devices while
refueling.
.Do not re-enter the vehicle while
pumping fuel.
(Continued)
Warning (Continued)
.Keep children away from the fuel
pump and never let children
pump fuel.
.Before touching the fill nozzle, touch a
metallic object to discharge static
electricity from your body.
.Fuel can spray out if the fuel cap is
opened too quickly. This spray can
happen if the tank is nearly full, and is
more likely in hot weather. Open the
fuel cap slowly and wait for any hiss
noise to stop, then unscrew the cap all
the way.
Turn the fuel cap counterclockwise to
remove. Fully insert and latch the fill nozzle,
begin fueling. For models with dual fuel
tanks, the fuel gauge shows an average of
both tanks. When refueling, refuel the
primary front tank first, then add fuel to the
auxiliary rear tank.
{Warning
Overfilling the fuel tank by more than
three clicks of a standard fill nozzle may
cause:
.Vehicle performance issues, including
engine stalling and damage to the fuel
system.
.Fuel spills.
.Under certain conditions, fuel fires.
Be careful not to spill fuel. Wait five seconds
after you have finished pumping before
removing the fill nozzle. Clean fuel from
painted surfaces as soon as possible. See
Exterior Care 0383. Reinstall the cap by
turning it clockwise until it clicks.
{Warning
If a fire starts while you are refueling, do
not remove the fill nozzle. Shut off the
flow of fuel by shutting off the pump or
by notifying the station attendant. Leave
the area immediately.

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276 Driving and Operating
Caution
If a new fuel cap is needed, get the right
type of cap from your dealer. The wrong
type of fuel cap may not fit properly,
may turn on the malfunction indicator
lamp, and could damage the fuel system
and emissions system. SeeMalfunction
Indicator Lamp (Check Engine Light) 0122.
Filling a Portable Fuel Container
{Warning
Never fill a portable fuel container while
it is in the vehicle. Static electricity
discharge from the container can ignite
the fuel vapor. You or others could be
badly burned and the vehicle could be
damaged. To help avoid injury to you
and others:
.Dispense fuel only into approved
containers.
.Do not fill a container while it is
inside a vehicle, in a vehicle's trunk, in
a pickup bed, or on any surface other
than the ground.
(Continued)
Warning (Continued)
.Bring the fill nozzle in contact with
the inside of the fill opening before
operating the nozzle. Maintain contact
until filling is complete.
.Keep sparks, flames, and smoking
materials away from fuel.
.Avoid using electronic devices while
pumping fuel.
.When transporting a fuel container or
other material that can catch fire in
the truck bed, secure the container to
prevent spills.
Trailer Towing
General Towing Information
Only use towing equipment that has been
designed for the vehicle. Contact your dealer
or trailering dealer for assistance with
preparing the vehicle to tow a trailer. Read
the entire section before towing a trailer.
To tow a disabled vehicle, see Transporting
a Disabled Vehicle 0379. To tow the vehicle
behind another vehicle such as a motor
home, see Recreational Vehicle Towing
0 380.
Driving Characteristics and
Towing Tips
{Warning
You can lose control when towing a
trailer if the correct equipment is not
used or the vehicle is not driven properly.
For example, if the trailer is too heavy or
the trailer brakes are inadequate for the
load, the vehicle may not stop as
expected. You and others could be
seriously injured. The vehicle may also be
damaged, and the repairs would not be
covered by the vehicle warranty. Pull a
trailer only if all the steps in this section
have been followed. Ask your dealer for
advice and information about towing a
trailer with the vehicle.
Driving with a Trailer
Trailering is different than just driving the
vehicle by itself. Trailering affects handling,
acceleration, braking, and durability.
Successful and safe trailering requires proper
use of the correct equipment.

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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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282 Driving and Operating
The GCWR can also be confirmed by
weighing the truck and trailer on a public
scale. The truck and trailer should be loaded
for the trip with passengers and cargo.
Gross Combined Weight (GCW) Alert
If equipped, the GCW Alert can display a
message in the Driver Information Center
(DIC), indicating that the estimated
combined weight of the vehicle and trailer
may exceed the vehicle’s GCWR, under
certain circumstances. See“Gross Combined
Weight Rating” above. The vehicle does not
actually measure the loaded weight of your
vehicle or trailer. It uses vehicle data to
estimate these weights after you begin
a trip. The alert will not activate unless:
.The feature is turned on in the trailering
application. See
Trailering App0296.
.The vehicle-trailer combination have been
used enough together for the software to
estimate the combined vehicle and trailer
weight.
.The estimated weight could exceed the
vehicle’s maximum GCWR.
If the GCW alert message is displayed, stop
the vehicle when it is safe and check the
vehicle and trailer weight using a scale. See
“Maximum Trailer Weight” below.
{Warning
Always determine the actual weights of
the loaded vehicle and trailer using a
vehicle scale before beginning a trip.
Never use the GCW Alert to determine
whether the vehicle and trailer are
properly loaded or overloaded. Do not
drive with an overloaded vehicle or
trailer. Death, serious injury, or property
damage could occur.
GCWR is only one of the maximum weight
ratings applicable to your vehicle and trailer.
The GCW Alert does not estimate whether the vehicle alone exceeds the GVWR, the
rear-axle weight exceeds GAWR-RR, the
trailer exceeds the Maximum Trailer Weight
Rating or the trailer tongue weight exceeds
the Maximum Tongue Weight Rating.
Always verify that the weight of the vehicle,
vehicle contents, trailer, trailer contents and
trailer tongue are below all of these
maximum weight ratings. See
“Maximum
Trailer Weight” below.
Gross Vehicle Weight Rating (GVWR)
For information about the vehicle's
maximum load capacity, see Vehicle Load
Limits 0210. When calculating the GVWR
with a trailer attached, the trailer tongue
weight must be included as part of the
weight the vehicle is carrying.
Maximum Trailer Weight
The maximum trailer weight rating is
calculated assuming the tow vehicle has a
driver, a front seat passenger, and all
required trailering equipment. This value
represents the heaviest trailer the vehicle
can tow, but it may be necessary to reduce
the trailer weight to stay within the GCWR,
GVWR, maximum trailer tongue load,
or GAWR-RR for the vehicle.