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156 Driving and Operating
The SBZA sensor covers a zone of
approximately one lane over from both
sides of the vehicle, or 3.5 m (11 ft). The
height of the zone is approximately between
0.5 m (1.5 ft) and 2 m (6 ft) off the ground.
This zone starts at approximately the middle
of the vehicle and goes back 5 m (16 ft).
How the System Works
The SBZA symbol lights up in the side
mirrors when the system detects a moving
vehicle in the next lane over that is in the
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 MirrorDisplayRight Side Mirror Display
When the vehicle is started, both outside
mirror SBZA 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
of a detected vehicle, this display will flash
as an extra warning not to change lanes.
SBZA can be disabled through the Driver
Information Center (DIC). See
Driver
Information Center (DIC) 081. If SBZA is
disabled by the driver, the SBZA mirror
displays will not light up.
When the System Does Not Seem to
Work Properly
SBZA displays may not come on when
passing a vehicle quickly, or for a stopped
vehicle. SBZA may alert to objects attached
to the vehicle, such as a bicycle, or object
extending out to either side of the vehicle.
This is normal system operation; the vehicle
does not need service.
SBZA 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. SBZA may not operate when the SBZA
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 Care0242. 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 SBZA 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 SBZA is disabled for any reason other
than the driver turning it off, the Side Blind
Zone Alert On option will not be available
on the personalization menu.
Driving with a Trailer
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.
Radio Frequency Information
See Radio Frequency Statement 0273.

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Driving and Operating 161
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.
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. Even if not
required, you should install extended side
view mirrors if your visibility is limited or
restricted while towing.
.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.
.It is recommended to perform the first oil
change before heavy towing.
.During the first 800 km (500 mi) of trailer
towing, do not drive over 80 km/h
(50 mph) and do not make starts at full
throttle.
.Vehicles can tow in D (Drive). Tow/Haul
Mode is recommended for heavier trailers.
SeeTow/Haul Mode 0145. If the
transmission downshifts too often, a
lower gear may be selected using Manual
Mode. See Manual Mode 0144.
If equipped, the following driver assistance
features should be turned off when towing
a trailer:
.Adaptive Cruise Control (ACC)
.Super Cruise Control
.Lane Keep Assist (LKA)
.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:
.Automatic Emergency Braking (AEB)
.Intelligent Brake Assist (IBA)
.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:
.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 0141.
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.

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Driving and Operating 163
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 the brake pedal, but do not shift into P (Park) yet. Turn the wheels into
the curb if facing downhill or into traffic
if facing uphill.
2. Have someone place chocks under the trailer wheels.
3. When the wheel chocks are in place, 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 wiring to the trailer before
backing the trailer into the water to prevent
damage to the electrical circuits on the
trailer. 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. Slowly back down the boat ramp until the boat is floating, but no further than
necessary.
2. Press and hold the brake pedal, but do not shift into P (Park) yet.
3. Have someone place chocks under the front wheels of the vehicle.
4. Gradually release the brake pedal to allow the chocks to absorb the load of
the trailer.

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164 Driving and Operating
5. Reapply the brake pedal. Then apply theparking brake and shift into P (Park).
6. Release the brake pedal.
Pulling the Trailer from the Water
To pull the trailer from the water: 1. Press and hold the brake pedal.
2. Start the engine and shift into a 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.
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 0251. It is especially important to
check the automatic transmission fluid,
engine oil, axle lubricant, belts, cooling
system, and brake system before and during
each trip.
Check periodically 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 0194.
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, durability,
and fuel economy. 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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184 Vehicle Care
10. Brake Master Cylinder Reservoir. SeeBrake Fluid 0197.
11. Windshield Washer Fluid Reservoir. See “Adding Washer Fluid” underWasher
Fluid 0196.
Engine Oil
For diesel engine vehicles, see “Engine Oil”
in the Duramax diesel supplement.
To ensure proper engine performance and
long life, careful attention must be paid to
engine oil. Following these simple, but
important steps will help protect your
investment:
.Use engine oil approved to the proper
specification and of the proper viscosity
grade. See “Selecting the Right Engine
Oil” in this section.
.Check the engine oil level regularly and
maintain the proper oil level. See
“Checking Engine Oil” and“When to Add
Engine Oil” in this section.
.Change the engine oil at the appropriate
time. SeeEngine Oil Life System 0186.
.Always dispose of engine oil properly. See
“What to Do with Used Oil” in this
section.
Checking Engine Oil
Check the engine oil level regularly, every
650 km (400 mi), especially prior to a long
trip. The engine oil dipstick handle is a loop.
See Engine Compartment Overview 0181 for
the location.
{Warning
The engine oil dipstick handle may be
hot; it could burn you. Use a towel or
glove to touch the dipstick handle.
If a low oil Driver Information Center (DIC)
message displays, check the oil level.
Follow these guidelines:
.To get an accurate reading, park the
vehicle on level ground. Check the engine
oil level after the engine has been off for
at least two hours. Checking the engine
oil level on steep grades or too soon after
engine shutoff can result in incorrect
readings. Accuracy improves when
checking a cold engine prior to starting.
Remove the dipstick and check the level.
.If unable to wait two hours, the engine
must be off for at least 15 minutes if the
engine is warm, or at least 30 minutes if
the engine is not warm. Pull out the dipstick, wipe it with a clean paper towel
or cloth, then push it back in all the way.
Remove it again, keeping the tip down,
and check the level.
When to Add Engine Oil
4.3L V6 Engine
6.6L V8 Engine
If the oil is below the cross-hatched area at
the tip of the dipstick and the engine has
been off for at least 15 minutes, add
1 L (1 qt) of the recommended oil and then
recheck the level. See “Selecting the Right
Engine Oil” later in this section for an

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Vehicle Care 215
Tire Terminology and Definitions
Air Pressure:The amount of air inside
the tire pressing outward on each
square inch of the tire. Air pressure is
expressed in kPa (kilopascal) or psi
(pounds per square inch).
Accessory Weight
:The combined
weight of optional accessories. Some
examples of optional accessories are
automatic transmission, power
windows, power seats, and air
conditioning.
Aspect Ratio
:The relationship of a
tire's height to its width.
Belt
:A rubber coated layer of cords
between the plies and the tread. Cords
may be made from steel or other
reinforcing materials.
Bead
:The tire bead contains steel
wires wrapped by steel cords that hold
the tire onto the rim.
Bias Ply Tire
:A pneumatic tire in which
the plies are laid at alternate angles
less than 90 degrees to the centerline
of the tread. Cold Tire Pressure
:The amount of air
pressure in a tire, measured in kPa
(kilopascal) or psi (pounds per square
inch) before a tire has built up heat
from driving. See Tire Pressure0217.
Curb Weight
:The weight of a motor
vehicle with standard and optional
equipment including the maximum
capacity of fuel, oil, and coolant, but
without passengers and cargo.
DOT Markings
:A code molded into the
sidewall of a tire signifying that the tire
is in compliance with the U.S.
Department of Transportation (DOT)
Motor Vehicle Safety Standards. The
DOT code includes the Tire Identification
Number (TIN), an alphanumeric
designator which can also identify the
tire manufacturer, production plant,
brand, and date of production.
GVWR
:Gross Vehicle Weight Rating.
See Vehicle Load Limits 0132.
GAWR FRT
:Gross Axle Weight Rating
for the front axle. See Vehicle Load
Limits 0132. GAWR RR
:Gross Axle Weight Rating
for the rear axle. See Vehicle Load
Limits 0132.
Intended Outboard Sidewall
:The side
of an asymmetrical tire that must
always face outward when mounted on
a vehicle.
Kilopascal (kPa)
:The metric unit for air
pressure.
Light Truck (LT-Metric) Tire
:A tire used
on light duty trucks and some
multipurpose passenger vehicles.
Load Index
:An assigned number
ranging from 1 to 279 that corresponds
to the load carrying capacity of a tire.
Maximum Inflation Pressure
:The
maximum air pressure to which a cold
tire can be inflated. The maximum air
pressure is molded onto the sidewall.
Maximum Load Rating
:The load rating
for a tire at the maximum permissible
inflation pressure for that tire.

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218 Vehicle Care
is necessary. If the inflation pressure is
low, add air until the recommended
pressure is reached. If the inflation
pressure is high, press on the metal
stem in the center of the tire valve to
release air.
Re-check the tire pressure with the tire
gauge.
Put the valve caps back on the valve
stems to keep out dirt and moisture.
Use only valve caps designed for the
vehicle by GM. TPMS sensors could be
damaged and would not be covered by
the vehicle warranty.
Tire Pressure Monitor System
The Tire Pressure Monitor System (TPMS)
uses radio and sensor technology to check
tire pressure levels. The TPMS sensors
monitor the air pressure in your tires and
transmit tire pressure readings to a receiver
located in the vehicle.
Each tire, including the spare (if provided),
should be checked monthly when cold and
inflated to the inflation pressure
recommended by the vehicle manufacturer
on the vehicle placard or tire inflationpressure label. (If your vehicle has tires of a
different size than the size indicated on the
vehicle placard or tire inflation pressure
label, you should determine the proper tire
inflation pressure for those tires.)
As an added safety feature, your vehicle has
been equipped with a tire pressure
monitoring system (TPMS) that illuminates a
low tire pressure telltale when one or more
of your tires is significantly under-inflated.
Accordingly, when the low tire pressure
telltale illuminates, you should stop and
check your tires as soon as possible, and
inflate them to the proper pressure. Driving
on a significantly under-inflated tire causes
the tire to overheat and can lead to tire
failure. Under-inflation also reduces fuel
efficiency and tire tread life, and may affect
the vehicle's handling and stopping ability.
Please note that the TPMS is not a
substitute for proper tire maintenance, and
it is the driver's responsibility to maintain
correct tire pressure, even if under-inflation
has not reached the level to trigger
illumination of the TPMS low tire pressure
telltale.
Your vehicle has also been equipped with a
TPMS malfunction indicator to indicate when
the system is not operating properly. TheTPMS malfunction indicator is combined
with the low tire pressure telltale. When the
system detects a malfunction, the telltale
will flash for approximately one minute and
then remain continuously illuminated. This
sequence will continue upon subsequent
vehicle start-ups as long as the malfunction
exists.
When the malfunction indicator is
illuminated, the system may not be able to
detect or signal low tire pressure as
intended. TPMS malfunctions may occur for
a variety of reasons, including the
installation of replacement or alternate tires
or wheels on the vehicle that prevent the
TPMS from functioning properly. Always
check the TPMS malfunction telltale after
replacing one or more tires or wheels on
your vehicle to ensure that the replacement
or alternate tires and wheels allow the
TPMS to continue to function properly.
See
Tire Pressure Monitor Operation 0218.
See Radio Frequency Statement 0273.
Tire Pressure Monitor Operation
This vehicle may have a Tire Pressure
Monitor System (TPMS). The TPMS is
designed to warn the driver when a low tire
pressure condition exists. TPMS sensors are

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Vehicle Care 225
Different Size Tires and Wheels
If wheels or tires are installed that are a
different size than the original equipment
wheels and tires, vehicle performance,
including its braking, ride and handling
characteristics, stability, and resistance to
rollover may be affected. If the vehicle has
electronic systems such as antilock brakes,
rollover airbags, traction control, electronic
stability control, or All-Wheel Drive, the
performance of these systems can also be
affected.
{Warning
If different sized wheels are used, there
may not be an acceptable level of
performance and safety if tires not
recommended for those wheels are
selected. This increases the chance of a
crash and serious injury. Only use GM
specific wheel and tire systems developed
for the vehicle, and have them properly
installed by a GM certified technician.
See Buying New Tires 0223 and
Accessories and Modifications 0178.
Uniform Tire Quality Grading
The following information relates to the
system developed by the United States
National Highway Traffic Safety
Administration (NHTSA), which grades
tires by treadwear, traction, and
temperature performance. This applies
only to vehicles sold in the United
States. The grades are molded on the
sidewalls of most passenger car tires.
The Uniform Tire Quality Grading
(UTQG) system does not apply to deep
tread, winter tires, compact spare tires,
tires with nominal rim diameters of
10 to 12 inches (25 to 30 cm), or to some
limited-production tires.
While the tires available on General
Motors passenger cars and light trucks
may vary with respect to these grades,
they must also conform to federal
safety requirements and additional
General Motors Tire Performance
Criteria (TPC) standards. Quality grades can be found where
applicable on the tire sidewall between
tread shoulder and maximum section
width. For example:
Treadwear 200 Traction AA Temperature A
All Passenger Car Tires Must Conform to
Federal Safety Requirements In Addition
To These Grades.
Treadwear
The treadwear grade is a comparative
rating based on the wear rate of the
tire when tested under controlled
conditions on a specified government
test course. For example, a tire graded
150 would wear one and one-half (1½)
times as well on the government course
as a tire graded 100. The relative
performance of tires depends upon the
actual conditions of their use, however,
and may depart significantly from the
norm due to variations in driving habits,
service practices and differences in road
characteristics and climate.