check engine CHEVROLET EXPRESS 2020 Get To Know Guide

Chevrolet Express Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
13882570) - 2020 - CRC - 11/1/19
Driving and Operating 211
controller should be installed by
your dealer or a qualified service
center.
If equipped, wiring provisions for an
aftermarket electric trailer brake
controller are included with the
vehicle as part of the trailer wiring
package. The harness contains the
following circuits:Electric Trailer
Brakes Dark Blue
Battery Feed Red/White
Brake Apply
Signal Light Blue
Ground Black
There are four blunt cut wires under
the floor carpeting in front of the
brake pedal. It will be necessary to
have a technician connect the
12-volt power to the engine
compartment fuse block.
Refer to the aftermarket electric
trailer brake controller owner's
manual to determine wire color
coding of the electric trailer brake controller. The wire colors on the
brake controller may be different
from the vehicle.
Trailer Lamps
Always check all trailer lamps are
working at the beginning of each
trip, and periodically on longer trips.
Turn Signals When Towing a
Trailer
When properly connected, the trailer
turn signals will illuminate to indicate
the vehicle is turning, changing
lanes, or stopping. When towing a
trailer, the arrows on the instrument
cluster will illuminate even if the
trailer is not properly connected or
the bulbs are burned out.
Tow/Haul Mode
Tow/Haul assists when pulling a
heavy trailer or a large or heavy
load. For instructions on how to
enter Tow/Haul mode, see
Tow/Haul
Mode 0175.
Tow/Haul Mode is designed to be
most effective when the vehicle and
trailer combined weight is at least 75% of the vehicle's Gross
Combined Weight Rating (GCWR).
See
“Trailer Weight ”under Trailer
Towing 0201.
Tow/Haul Mode is most useful when
towing a heavy trailer or carrying a
large or heavy load:
. through rolling terrain
. in stop-and-go traffic
. in busy parking lots
Operating the vehicle in Tow/Haul
Mode when lightly loaded or not
towing will not cause damage;
however, it is not recommended and
may result in unpleasant engine and
transmission driving characteristics
and reduced fuel economy.
Trailer Sway
Control (TSC)
Vehicles with StabiliTrak/Electronic
Stability Control (ESC) have a
Trailer Sway Control (TSC) feature.
Trailer sway is unintended
side-to-side motion of a trailer while
towing. If the vehicle is towing a
trailer and the TSC detects that

Chevrolet Express Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
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212 Driving and Operating
sway is increasing, the vehicle
brakes are selectively applied at
each wheel, to help reduce
excessive trailer sway. If equipped
with the Integrated Trailer Brake
Control (ITBC) system, and the
trailer has an electric brake system,
StabiliTrak/ESC may also apply the
trailer brakes.
If TSC is enabled, the Traction
Control System (TCS)/StabiliTrak/
ESC warning light will flash on the
instrument cluster. Reduce vehicle
speed by gradually removing your
foot from the accelerator. If trailer
sway continues, StabiliTrak/ESC
can reduce engine torque to help
slow the vehicle. TSC will not
function if StabiliTrak/ESC is turned
off. SeeTraction Control/Electronic
Stability Control 0178.
{Warning
Trailer sway can result in a crash
and in serious injury or death,
even if the vehicle is equipped
with TSC.
If the trailer begins to sway,
reduce vehicle speed by
gradually removing your foot from
the accelerator. Then pull over to
check the trailer and vehicle to
help correct possible causes,
including an improperly or
overloaded trailer, unrestrained
cargo, improper trailer hitch
configuration, or improperly
inflated or incorrect vehicle or
trailer tires. See Towing
Equipment 0208 for trailer ratings
and hitch setup
recommendations.
Trailer Tires
Special Trailer (ST) tires differ from
vehicle tires. Trailer tires are
designed with stiff sidewalls to help
prevent sway and to support heavy loads. These features can make it
difficult to determine if the trailer tire
pressures are low only based on a
visual inspection.
Always check all trailer tire
pressures before each trip when the
tires are cool. Low trailer tire
pressure is a leading cause of trailer
tire blow-outs.
Trailer tires deteriorate over time.
The trailer tire sidewall will show the
week and year the tire was
manufactured. Many trailer tire
manufacturers recommend
replacing tires more than six
years old.
Overloading is another leading
cause of trailer tire blow-outs. Never
load your trailer with more weight
than the tires are designed to
support. The load rating is located
on the trailer tire sidewall.
Always know the maximum speed
rating for the trailer tires before
driving. This may be significantly
lower than the vehicle tire speed
rating. The speed rating may be on
the trailer tire sidewall. If the speed

Chevrolet Express Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
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Driving and Operating 213
rating is not shown, the default
trailer tire speed rating is 105 km/h
(65 mph).Conversions and
Add-Ons
Add-On Electrical
Equipment
{Warning
The Data Link Connector (DLC) is
used for vehicle service and
Emission Inspection/Maintenance
testing. SeeMalfunction Indicator
Lamp (Check Engine Light) 093.
A device connected to the DLC —
such as an aftermarket fleet or
driver-behavior tracking device —
may interfere with vehicle
systems. This could affect vehicle
operation and cause a crash.
Such devices may also access
information stored in the vehicle’s
systems.
Caution
Some electrical equipment can
damage the vehicle or cause
components to not work and
would not be covered by the
vehicle warranty. Always check
with your dealer before adding
electrical equipment.
Add-on equipment can drain the
vehicle's 12-volt battery, even if the
vehicle is not operating.
The vehicle has an airbag system.
Before attempting to add anything
electrical to the vehicle, see
Servicing the Airbag-Equipped
Vehicle 053 and
Adding Equipment to the
Airbag-Equipped Vehicle 054.

Chevrolet Express Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
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214 Vehicle Care
Vehicle Care
General Information
General Information . . . . . . . . . . 215
California Proposition65 Warning . . . . . . . . . . . . . . . . . 215
California Perchlorate Materials Requirements . . . . . 216
Accessories and Modifications . . . . . . . . . . . . . . . . 216
Vehicle Checks
Doing Your OwnService Work . . . . . . . . . . . . . . . 216
Hood . . . . . . . . . . . . . . . . . . . . . . . . . 217
Engine Compartment Overview . . . . . . . . . . . . . . . . . . . . 218
Engine Oil . . . . . . . . . . . . . . . . . . . . 222
Engine Oil Life System . . . . . . . 224
Automatic Transmission Fluid (6-Speed Transmission) . . . . . 225
Automatic Transmission Fluid (8-Speed Transmission) . . . . . 228
Engine Air Cleaner/Filter . . . . . . 229
Cooling System . . . . . . . . . . . . . . 230
Engine Overheating . . . . . . . . . . 235
Engine Fan . . . . . . . . . . . . . . . . . . . 236
Power Steering Fluid . . . . . . . . . 237
Washer Fluid . . . . . . . . . . . . . . . . . 237 Brakes . . . . . . . . . . . . . . . . . . . . . . . 238
Brake Fluid . . . . . . . . . . . . . . . . . . . 239
Battery - North America . . . . . . 240
Rear Axle . . . . . . . . . . . . . . . . . . . . 241
Noise Control System . . . . . . . . 241
Starter Switch Check . . . . . . . . . 242
Automatic Transmission Shift
Lock Control Function
Check . . . . . . . . . . . . . . . . . . . . . . . 243
Ignition Transmission Lock Check . . . . . . . . . . . . . . . . . . . . . . . 243
Park Brake and P (Park) Mechanism Check . . . . . . . . . . 243
Wiper Blade Replacement . . . . 244
Windshield Replacement . . . . . 244
Headlamp Aiming
Front Headlamp Aiming . . . . . . 245
Bulb Replacement
Bulb Replacement . . . . . . . . . . . . 245
Halogen Bulbs . . . . . . . . . . . . . . . . 245
Front Turn Signal, Sidemarker, and Parking Lamps . . . . . . . . . 245
Taillamps . . . . . . . . . . . . . . . . . . . . . 246
Center High-Mounted Stoplamp (CHMSL) . . . . . . . . . 247
License Plate Lamp . . . . . . . . . . 247
Electrical System
Electrical System Overload . . . 248 Fuses and Circuit Breakers . . . 249
Engine Compartment Fuse
Block . . . . . . . . . . . . . . . . . . . . . . . . 249
Floor Console Fuse Block . . . . 253
Wheels and Tires
Tires . . . . . . . . . . . . . . . . . . . . . . . . . . 255
All-Season Tires . . . . . . . . . . . . . . 256
Winter Tires . . . . . . . . . . . . . . . . . . 256
Tire Sidewall Labeling . . . . . . . . 257
Tire Designations . . . . . . . . . . . . . 259
Tire Terminology and Definitions . . . . . . . . . . . . . . . . . . 260
Tire Pressure . . . . . . . . . . . . . . . . . 263
Tire Pressure Monitor System . . . . . . . . . . . . . . . . . . . . . . 264
Tire Pressure Monitor
Operation . . . . . . . . . . . . . . . . . . . 265
Tire Inspection . . . . . . . . . . . . . . . . 268
Tire Rotation . . . . . . . . . . . . . . . . . 268
Dual Tire Rotation . . . . . . . . . . . . 270
When It Is Time for New Tires . . . . . . . . . . . . . . . . . . . . . . . . 270
Buying New Tires . . . . . . . . . . . . . 271
Different Size Tires and Wheels . . . . . . . . . . . . . . . . . . . . . . 272
Uniform Tire Quality Grading . . . . . . . . . . . . . . . . . . . . . 273
Wheel Alignment and Tire Balance . . . . . . . . . . . . . . . . . . . . . 274
Wheel Replacement . . . . . . . . . . 275

Chevrolet Express Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
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218 Vehicle Care
3. Lift the hood and release thehood prop rod from its retainer,
in the front of the engine
compartment. Securely insert
the rod end into the slot
marked with an arrow, on the
underside of the hood.
To close the hood: 1. Before closing the hood, be sure all filler caps are on
properly, and all tools are
removed.
2. Lift the hood and remove the hood prop rod from the
underside of the hood. Return
the prop rod to its retainer. The prop rod must click into place
when returning it to the retainer
to prevent hood damage.
3. Lower the hood 20 cm (8 in) above the vehicle and release
it. Check to make sure the
hood is latched completely.
Repeat this process with
additional force if necessary.
{Warning
Do not drive the vehicle if the
hood is not latched completely.
The hood could open fully, block
your vision, and cause a crash.
You or others could be injured.
Always close the hood completely
before driving.
Engine Compartment
Overview
For diesel engine vehicles, see the
Duramax diesel supplement.

Chevrolet Express Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
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220 Vehicle Care
1.Battery - North America 0240.
2. Radiator Pressure Cap. See Cooling System 0230.
3. Coolant Recovery Tank. See Cooling System 0230.
4. Engine Cooling Fan (Out of View). See Cooling System
0 230.
5. Engine Air Cleaner/Filter 0229.
6. Engine Oil Dipstick. See “Checking Engine Oil” under
Engine Oil 0222.
7. Engine Oil Fill Cap. See “When
to Add Engine Oil” under
Engine Oil 0222.
8. Power Steering Fluid Reservoir. See Power Steering
Fluid 0237.
9. Engine Compartment Fuse
Block 0249.
10. Brake Master Cylinder Reservoir. See Brake Fluid
0 239. 11. Windshield Washer Fluid
Reservoir. See “Adding Washer
Fluid” under Washer Fluid
0 237.

Chevrolet Express Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
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222 Vehicle Care
1.Battery - North America 0240.
2. Radiator Pressure Cap. See Cooling System 0230.
3. Coolant Recovery Tank. See Cooling System 0230.
4. Automatic Transmission Fluid Dipstick. See “Checking the
Fluid Level” underAutomatic
Transmission Fluid (6-Speed
Transmission) 0225 or
Automatic Transmission Fluid
(8-Speed Transmission) 0228.
5. Engine Oil Fill Cap. See “When
to Add Engine Oil” under
Engine Oil 0222.
6. Engine Oil Dipstick. See “Checking Engine Oil” under
Engine Oil 0222.
7. Engine Cooling Fan (Out of View). See Cooling System
0 230.
8. Engine Air Cleaner/Filter 0229.
9. Power Steering Fluid Reservoir. See Power Steering
Fluid 0237. 10.
Engine Compartment Fuse
Block 0249.
11. Brake Master Cylinder Reservoir. See Brake Fluid
0 239.
12. Windshield Washer Fluid Reservoir. See “Adding Washer
Fluid” under Washer Fluid
0 237.
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. See Engine Oil
Life System 0224.
. 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
0218 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.

Chevrolet Express Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
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Vehicle Care 223
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
6.0L 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 explanation of what kind of oil to
use. For engine oil crankcase
capacity, see Capacities and
Specifications 0318.
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
0 218 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.

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Vehicle Care 225
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
be reset. 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)
099.
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)
099.
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.

Chevrolet Express Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
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226 Vehicle Care
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 inMaintenance
Schedule 0305, and be sure to use
the transmission fluid listed in
Recommended Fluids and
Lubricants 0313.
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