warning GMC SIERRA 2024 Owners Manual

GMC Sierra/Sierra Denali 2500 HD/3500 HD Owner Manual (GMNA-
Localizing-U.S./Canada-16908340) - 2024 - CRC - 12/13/22
Driving and Operating 269
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

GMC Sierra/Sierra Denali 2500 HD/3500 HD Owner Manual (GMNA-
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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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274 Driving and Operating
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 fill nozzle is
inserted too quickly. This spray can
happen if the tank is nearly full, and is
more likely in hot weather. Insert the
fill nozzle slowly and wait for any hiss
noise to stop before beginning to
flow fuel.
The capless refueling system does not have
a fuel cap. Fully insert and latch the fill
nozzle, begin fueling.
{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. Push the fuel door
closed.
{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. Filling the Tank with a Portable Fuel
Container
If the vehicle runs out of fuel and must be
filled from a portable fuel container:
1. Locate the capless funnel adapter.
2. Insert and latch the funnel into the
capless fuel system.
{Warning
Attempting to refuel from a portable fuel
container without using the funnel
adapter may cause fuel spillage and
damage the capless fuel system. This
could cause a fire. You or others could be
badly burned and the vehicle could be
damaged.
3. Remove and clean the funnel adapter and return it to the storage location.

GMC Sierra/Sierra Denali 2500 HD/3500 HD Owner Manual (GMNA-
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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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Driving and Operating 277
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 towing a
trailer.
When towing a trailer:
.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 80 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 Mode0227. If the transmission
downshifts too often, a lower gear may
be selected using Manual Mode. See
Manual Mode 0226.
The following advanced driver assistance
features should be turned off when towing
a trailer, and may turn off automatically
when a trailer is detected:
.Park Assist
.Reverse Automatic Braking (RAB)
.Rear Cross Traffic Alert (RCTA)
.Rear Cross Traffic Braking (RCTB)
.Lane Change Alert (LCA)
.Super Cruise and Adaptive Cruise Control
(ACC), unless equipped with trailering
functionality, see Adaptive Cruise Control
(Camera) 0241.
Automatic Emergency Braking (AEB) and
Front Pedestrian Braking (FPB) should be set
to Alert unless equipped with Super Cruise.
Do not use Automatic Parking Assist (APA)
while towing a trailer.
{Warning
To prevent serious injury or death from
carbon monoxide (CO), when towing a
trailer:
.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 0222.
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

GMC Sierra/Sierra Denali 2500 HD/3500 HD Owner Manual (GMNA-
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278 Driving and Operating
and attachments, safety chains, electrical
connectors, lamps, tires, and mirrors. See
Towing Equipment0284. If the trailer has
electric brakes, start the combination
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 Turns
Caution
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 0321.
Viewing Systems
If equipped, the viewing systems on the
vehicle can improve visibility while hitching,
backing, and driving with a trailer. See
Advanced Driver Assistance Systems 0252.

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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.