engine oil CHEVROLET EXPRESS CARGO 2021 Owner's Guide

Chevrolet Express Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
14583525) - 2021 - CRC - 12/9/20
Vehicle Care 185
explanation of what kind of oil to use. For
engine oil crankcase capacity, seeCapacities
and Specifications 0261.
Caution
Do not add too much oil. Oil levels above
or below the acceptable operating range
shown on the dipstick are harmful to the
engine. If the oil level is above the
operating range (i.e., the engine has so
much oil that the oil level gets above the
cross-hatched area that shows the proper
operating range), the engine could be
damaged. Drain the excess oil or limit
driving of the vehicle, and seek a service
professional to remove the excess oil.
See Engine Compartment Overview 0181 for
the location of the engine oil fill cap.
Add enough oil to put the level somewhere
in the proper operating range. Push the
dipstick all the way back in when through.
Selecting the Right Engine Oil
Selecting the right engine oil depends on
both the proper oil specification and
viscosity grade. See Recommended Fluids
and Lubricants 0257. Specification
Use full synthetic engine oils that meet the
dexos1 specification. Engine oils that have
been approved by GM as meeting the
dexos1 specification are marked with the
dexos1 approved logo. See
www.gmdexos.com.
Caution
Failure to use the recommended engine
oil or equivalent can result in engine
damage not covered by the vehicle
warranty.
Viscosity Grade
Use SAE 5W-30 viscosity grade engine oil.
Cold Temperature Operation: In an area of
extreme cold, where the temperature falls
below −29 °C (−20 °F), an SAE 0W-30 oil may
be used. An oil of this viscosity grade will
provide easier cold starting for the engine at extremely low temperatures. When selecting
an oil of the appropriate viscosity grade, it
is recommended to select an oil of the
correct specification. See
“Specification”
earlier in this section.
Engine Oil Additives/Engine Oil Flushes
Do not add anything to the oil. The
recommended oils meeting the dexos1
specification are all that is needed for good
performance and engine protection.
Engine oil system flushes are not
recommended and could cause engine
damage not covered by the vehicle
warranty.
What to Do with Used Oil
Used engine oil contains certain elements
that can be unhealthy for your skin and
could even cause cancer. Do not let used oil
stay on your skin for very long. Clean your
skin and nails with soap and water, or a
good hand cleaner. Wash or properly
dispose of clothing or rags containing used
engine oil. See the manufacturer's warnings
about the use and disposal of oil products.
Used oil can be a threat to the environment.
If you change your own oil, be sure to drain
all the oil from the filter before disposal.

Chevrolet Express Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
14583525) - 2021 - CRC - 12/9/20
186 Vehicle Care
Never dispose of oil by putting it in the
trash or pouring it on the ground, into
sewers, or into streams or bodies of water.
Recycle it by taking it to a place that
collects used oil.
Engine Oil Life System
When to Change Engine Oil
This vehicle has a computer system that
indicates when to change the engine oil and
filter. This is based on a combination of
factors which include engine revolutions,
engine temperature, and miles driven. Based
on driving conditions, the mileage at which
an engine oil change is indicated can vary
considerably. For the oil life system to work
properly, the system must be reset every
time the oil is changed.
When the system has calculated that oil life
has been diminished, it indicates that an oil
change is necessary. A CHANGE ENGINE OIL
SOON message comes on. Change the oil as
soon as possible within the next 1 000 km
(600 mi). It is possible that, if driving under
the best conditions, the oil life system
might indicate that an oil change is not
necessary for up to a year. The engine oil
and filter must be changed at least once a
year and, at this time, the system must bereset. Your dealer has trained service people
who will perform this work and reset the
system. It is also important to check the oil
regularly over the course of an oil drain
interval and keep it at the proper level.
If the system is ever reset accidentally, the
oil must be changed at 5 000 km (3,000 mi)
since the last oil change. Remember to reset
the oil life system whenever the oil is
changed.
How to Reset the Engine Oil Life System
Reset the system whenever the engine oil is
changed so that the system can calculate
the next engine oil change.
To reset the Engine Oil Life System on most
models:
1. Display the OIL LIFE REMAINING on the DIC. See Driver Information Center (DIC)
0 81.
2. Press and hold
Von the DIC while the
Oil Life display is active. The oil life will
change to 100%.
The oil life system can also be reset as
follows: 1. Display the OIL LIFE REMAINING on the DIC. See Driver Information Center (DIC)
0 81. 2. Fully press and release the accelerator
pedal three times within five seconds.
If the display shows 100%, the system is
reset.
If the CHANGE ENGINE OIL SOON message
comes back on when the vehicle is started,
the engine oil life system has not reset.
Repeat the procedure.
Automatic Transmission Fluid
(6-Speed Transmission)
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. If a small leak is
suspected, use the following procedures to
check the fluid level. However, if there is a
large leak, it may be necessary to have the
vehicle towed to a dealer and have it
repaired before driving the vehicle further.
Change the fluid and filter at the intervals
listed in Maintenance Schedule 0251, and be
sure to use the transmission fluid listed in
Recommended Fluids and Lubricants 0257.

Chevrolet Express Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
14583525) - 2021 - CRC - 12/9/20
Vehicle Care 187
How to Check Automatic Transmission
Fluid
Because this operation can be difficult, it is
recommended to have this check done at
your dealer, which can monitor the
transmission temperature. The transmission
fluid level increases with temperature. To
obtain a highly accurate fluid level check,
the transmission temperature must be
measured.
If it is decided to check the fluid level, be
sure to follow all the instructions here, or a
false reading on the dipstick may occur.
Caution
Too much or too little fluid can damage
the transmission. Too much can mean
that some of the fluid could come out
and fall on hot engine parts or exhaust
system parts, starting a fire. Too little
fluid could cause the transmission to
overheat. Be sure to get an accurate
reading if checking the transmission fluid.Wait at least 30 minutes with the engine
off, before checking the transmission fluid
level if the vehicle has been driven:
.In hot weather, when outside
temperatures are above 32 °C (90 °F).
.The vehicle is heavily loaded.
.At high speed for quite a while in hot
weather.
.In heavy traffic and hot weather.
.While pulling a trailer.
After driving under these conditions, a hot
check can be performed. The fluid should be
hot, which is 71 °C to 93 °C (160 °F to
200 °F).
A cold fluid level check can be performed
after the vehicle has been sitting for eight
hours or more with the engine off, but this
is used only as a reference. Let the engine
run at idle for five minutes if the outside
temperature is between 15 °C to 32 °C (60 °F
to 90 °F). Should the fluid level be low
during this cold check, the fluid must be
checked warm or hot before adding fluid.
If the outside temperature is colder than
15 °C (60 °F) or hotter than 32 °C (90 °F), a
cold check cannot be performed. A warm fluid level check can be performed
by driving the vehicle under lightly loaded
conditions and outside temperatures
between 10 °C to 27 °C (50 °F to 80 °F). The
vehicle should be driven for at least 24 km
(15 mi) before performing a warm check.
Checking the fluid warm or hot will give a
more accurate reading of the fluid level than
a cold check.
Because the vehicle is equipped with a
high-efficiency air-to-oil cooler, the
transmission fluid temperature may not
reach the required hot fluid level checking
temperature under normal lightly loaded
driving vehicle conditions.
Checking the Fluid Level
Prepare the vehicle:
1. Park the vehicle on a level place. Keep the engine running.
2. With the parking brake applied, place the shift lever in P (Park).
3. With a foot on the brake pedal, move the shift lever through each gear range,
pausing for about three seconds in each
range. When M is reached, move the
selector from M1 through M3. Then,
position the shift lever in P (Park).

Chevrolet Express Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
14583525) - 2021 - CRC - 12/9/20
Vehicle Care 191
Caution
If the air cleaner/filter is off, dirt can
easily get into the engine, which could
damage it. Always have the air cleaner/
filter in place when driving.
Cooling System
The cooling system allows the engine to
maintain the correct working temperature.
4.3L V6 Engine
1. Radiator Pressure Cap
2. Coolant Recovery Tank
3. Engine Cooling Fan (Out of View)
6.6L V8 Engine
1. Radiator Pressure Cap
2. Coolant Recovery Tank
3. Engine Cooling Fan (Out of View)
{Warning
An underhood electric fan can start up
even when the engine is not running and
can cause injury. Keep hands, clothing,
and tools away from any underhood
electric fan.
{Warning
Do not touch heater or radiator hoses,
or other engine parts. They can be very
hot and can burn you. Do not run the
engine if there is a leak; all coolant could
leak out. That could cause an engine fire
and can burn you. Fix any leak before
driving the vehicle.
Engine Coolant
The cooling system in the vehicle is filled
with DEX-COOL engine coolant. This coolant
is designed to remain in the vehicle for
5 years or 240 000 km (150,000 mi),
whichever occurs first.
The following explains the cooling system
and how to check and add coolant when it
is low. If there is a problem with engine
overheating, seeEngine Overheating 0194.
What to Use
{Warning
Plain water, or other liquids such as
alcohol, can boil before the proper
coolant mixture will. With plain water or
(Continued)

Chevrolet Express Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
14583525) - 2021 - CRC - 12/9/20
192 Vehicle Care
Warning (Continued)
the wrong mixture, the engine could get
too hot but there would not be an
overheat warning. The engine could catch
fire and you or others could be burned.
Use a 50/50 mixture of clean, drinkable
water and DEX-COOL coolant. If using this
mixture, nothing else needs to be added.
This mixture:
.Gives freezing protection down to −37 °C
(−34 °F), outside temperature.
.Gives boiling protection up to 129 °C
(265 °F), engine temperature.
.Protects against rust and corrosion.
.Will not damage aluminum parts.
.Helps keep the proper engine
temperature.
Caution
Do not use anything other than a mix of
DEX-COOL coolant that meets GM
Standard GMW3420 and clean, drinkable
water. Anything else can cause damage
to the engine cooling system and the
vehicle, which would not be covered by
the vehicle warranty. Never dispose of engine coolant by putting
it in the trash, pouring it on the ground,
or into sewers, streams, or bodies of water.
Have the coolant changed by an authorized
service center, familiar with legal
requirements regarding used coolant
disposal. This will help protect the
environment and your health.
Checking Coolant
The vehicle must be on a level surface when
checking the coolant level.
Check to see if coolant is visible in the
coolant recovery tank. If the coolant inside
the coolant recovery tank is boiling, do not
do anything else until it cools down.
If coolant is visible but the coolant level is
not at or above the indicated mark, add a
50/50 mixture of clean, drinkable water and
DEX-COOL coolant at the coolant recovery
tank, but be sure the cooling system is cool
before this is done.
The coolant recovery tank cap has this
symbol on it.
When the engine is cold, the coolant level
should be at or above the COLD FILL mark.
If it is not, there could be a leak in the
cooling system.
If the coolant is low, add the coolant or take
the vehicle to a dealer for service.

Chevrolet Express Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
14583525) - 2021 - CRC - 12/9/20
Vehicle Care 193
How to Add Coolant to the Recovery
Tank for Gasoline Engines
{Warning
Spilling coolant on hot engine parts can
burn you. Coolant contains ethylene
glycol and it will burn if the engine parts
are hot enough.
{Warning
Plain water, or other liquids such as
alcohol, can boil before the proper
coolant mixture will. With plain water or
the wrong mixture, the engine could get
too hot but there would not be an
overheat warning. The engine could catch
fire and you or others could be burned.
{Warning
Steam and scalding liquids from a hot
cooling system are under pressure.
Turning the pressure cap, even a little,
can cause them to come out at high
speed and you could be burned. Never
turn the cap when the cooling system,(Continued)
Warning (Continued)
including the pressure cap, is hot. Wait
for the cooling system and pressure cap
to cool.
Caution
Failure to follow the specific coolant fill
procedure could cause the engine to
overheat and could cause system
damage. If coolant is not visible in the
surge tank, contact your dealer.
If coolant is needed, add the proper
DEX-COOL coolant mixture at the coolant
recovery tank.
How to Add Coolant to the Radiator
{Warning
Steam and scalding liquids from a hot
cooling system are under pressure.
Turning the pressure cap, even a little,
can cause them to come out at high
speed and you could be burned. Never
turn the cap when the cooling system, (Continued)
Warning (Continued)
including the pressure cap, is hot. Wait
for the cooling system and pressure cap
to cool.
If coolant is needed, add the proper mixture
directly to the radiator, but be sure the
cooling system is cool before this is done.
1. Remove the radiator pressure cap when the cooling system, including the
radiator pressure cap and upper radiator
hose, is no longer hot. Turn the pressure
cap slowly counterclockwise until it first
stops. Do not press down while turning
the pressure cap.
If a hiss is heard, wait for that to stop.
A hiss means there is still some
pressure left.
2. Keep turning the pressure cap, but now push down as you turn it. Remove the
pressure cap.

Chevrolet Express Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
14583525) - 2021 - CRC - 12/9/20
208 Vehicle Care
FusesUsage
18 A/C
19 Engine control module battery
20 Left stop/turn cutaway lamp
21 Left stop/turn trailer lamp
22 Right stop/turn cutaway lamp
23 NOX Sensor (Diesel only)
24 Fuel pump 25 Auxiliary power outlet
26 Body control module 3 27 Special equipment option
28 Airbag
29 Steering wheel sensor
30 Engine control module ignition
31 Transmission control module Ignition Fuses
Usage
32 Transmission control module 1 battery
33 Rear parking aid module
34 NOX Sensor (Diesel only)
35 Fuel heater control module (Diesel only)
36 Fuel system control module battery
41 Transmission control module 2, battery
signal
42 Trailer wiring
43 Electro viscous fan clutch (Diesel only)
44 Starter solenoid 45 Engine control module, powertrain signal 2
46 DC-AC inverter 47 –
51 Left high-beam headlamp Fuses
Usage
52 Right high-beam headlamp
53 Left low-beam headlamp
54 Right low-beam headlamp
55 Wipers
56 Canister vent solenoid
58 Body control module 2
59 Body control module 1 61 Engine oil solenoid/ Crankcase vent heater
(Diesel only)
62 O2 sensor 2
63 –
64 Mass airflow/ Canister vent
65 Ignition coils/injectors - odd
66 Daytime running lamps 2
67 Daytime running lamps 1

Chevrolet Express Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
14583525) - 2021 - CRC - 12/9/20
Vehicle Care 209
FusesUsage
68 Auxiliary stoplamps
69 External power for trailer
70 Upfitter stoplamps 71 Fuel heater/FlexFuel sensor
72 Body control module 6
73 Lighter/Data link connector
74 Front blower 75 Engine control module
76 Soot sensors (Diesel only)
77 O2 sensor 1
78 Engine control module/ Powertrain signal 1
79 Ignition coils/injectors - even Relays
Usage
15 Run/Crank
37 NOX Sensor (Diesel only)
38 Fuel pump
39 Crank
40 A/C compressor 48 Electro viscous fan clutch (Diesel only)
49 Powertrain 50 –
57 –
60 – Auxiliary Fuse Block
This component is near the fuse block in the
engine compartment
Fuses Usage
MR-1 Upfitter 1
MR-2 Upfitter 2
MR-3 Upfitter power control
Relays Usage
MR Rel 1 Upfitter 1
MR Rel 2 Upfitter 2

Chevrolet Express Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
14583525) - 2021 - CRC - 12/9/20
Vehicle Care 245
Brake System
Visually inspect brake lines and hoses for
proper hook-up, binding, leaks, cracks,
chafing, etc. Inspect disc brake pads for wear
and rotors for surface condition. Inspect
drum brake linings/shoes for wear or cracks.
Inspect all other brake parts.
Steering, Suspension, and Chassis
Components
Visually inspect steering, suspension, and
chassis components for damaged, loose,
or missing parts or signs of wear at least
once a year.
Inspect power steering for proper
attachment, connections, binding, leaks,
cracks, chafing, etc.
Visually check constant velocity joint boots
and axle seals for leaks.
Lubricate the upper and lower control arm
ball joints, at least every other engine oil
change.
Lubricate the tie rod ball joints, idler arm
pivot shaft bearings, idler arm socket, and
pitman arm socket, at least every other
engine oil change.
Caution
Lubrication of applicable steering/
suspension points should not be done
unless the temperature is−12 °C (10 °F) or
higher, or damage could result.
Body Component Lubrication
Lubricate all key lock cylinders, hood hinges,
liftgate hinges, and the fuel door hinge
unless the components are plastic. Applying
silicone grease on weatherstrips with a clean
cloth will make them last longer, seal better,
and not stick or squeak.
Underbody Maintenance
At least twice a year, spring and fall, use
plain water to flush dirt and debris from the
vehicle's underbody. Your dealer or an
underbody car washing system can do this.
If not removed, rust and corrosion can
develop.
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 fluid. Contaminated
fluid will decrease the life of the transfer
case and/or axles and should be replaced.
Sheet Metal Damage
If the vehicle is damaged and requires sheet
metal repair or replacement, make sure the
body repair shop applies anti-corrosion
material to parts repaired or replaced to
restore corrosion protection.
Original manufacturer replacement parts will
provide the corrosion protection while
maintaining the vehicle warranty.
Finish Damage
Quickly repair minor chips and scratches
with touch-up materials available from your
dealer to avoid corrosion. Larger areas of
finish damage can be corrected in your
dealer's body and paint shop.
Chemical Paint Spotting
Airborne pollutants can fall upon and attack
painted vehicle surfaces causing blotchy,
ring-shaped discolorations, and small,
irregular dark spots etched into the paint
surface. See “Finish Care” previously in this
section.

Chevrolet Express Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
14583525) - 2021 - CRC - 12/9/20
250 Service and Maintenance
Service and Maintenance
General Information
General Information . . . . . . . . . . . . . . . . . . . 250
Maintenance Schedule
Maintenance Schedule . . . . . . . . . . . . . . . . . 251
Special Application Services
Special Application Services . . . . . . . . . . . . 255
Additional Maintenance and Care
Additional Maintenance and Care . . . . . . 255
Recommended Fluids, Lubricants, and
Parts
Recommended Fluids and Lubricants . . . 257
Maintenance Replacement Parts . . . . . . . 258
Maintenance Records
Maintenance Records . . . . . . . . . . . . . . . . . . 259
General Information
This maintenance section applies to vehicles
with a gasoline engine. For diesel engine
vehicles, see "Maintenance Schedule" in the
Duramax diesel supplement.
Your vehicle is an important investment.
This section describes the required
maintenance for the vehicle. Follow this
schedule to help protect against major repair
expenses resulting from neglect or
inadequate maintenance. It may also help to
maintain the value of the vehicle if it is
sold. It is the responsibility of the owner to
have all required maintenance performed.
Your dealer has trained technicians who can
perform required maintenance using genuine
replacement parts. They have up-to-date
tools and equipment for fast and accurate
diagnostics. Many dealers have extended
evening and Saturday hours, courtesy
transportation, and online scheduling to
assist with service needs.
Your dealer recognizes the importance of
providing competitively priced maintenance
and repair services. With trained technicians,
the dealer is the place for routinemaintenance such as oil changes and tire
rotations and additional maintenance items
like tires, brakes, batteries, and wiper blades.
Caution
Damage caused by improper maintenance
can lead to costly repairs and may not be
covered by the vehicle warranty.
Maintenance intervals, checks,
inspections, recommended fluids, and
lubricants are important to keep the
vehicle in good working condition.
Do not have chemical flushes that are not
approved by GM performed on the
vehicle. The use of flushes, solvents,
cleaners, or lubricants that are not
approved by GM could damage the
vehicle, requiring expensive repairs that
are not covered by the vehicle warranty.
The Tire Rotation and Required Services are
the responsibility of the vehicle owner. It is
recommended to have your dealer perform
these services every 12 000 km/7,500 mi.
Proper vehicle maintenance helps to keep
the vehicle in good working condition,
improves fuel economy, and reduces vehicle
emissions.