overheating CHEVROLET EXPRESS 2021 Owners Manual

Chevrolet Express Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
15555951) - 2022 - CRC - 1/27/22
Instruments and Controls 71
The 110/120 volt power outlet is on the
instrument panel.
An indicator light on the outlet turns on to
show it is in use. The light comes on when
the ignition is on, equipment requiring less
than 150 watts is plugged into the outlet,
and no system fault is detected.
The indicator light does not come on when
the ignition is off, or if the equipment is not
fully seated into the outlet.
If equipment is connected using more than
150 watts or a system fault is detected, a
protection circuit shuts off the power supply
and the indicator light turns off. To reset
the circuit, unplug the item and plug it back
in or turn the Retained Accessory Power
(RAP) off and then back on. SeeRetained
Accessory Power (RAP) 0133.
The power outlet is not designed for the
following, and may not work properly if
they are plugged in:
.Equipment with high initial peak wattage,
such as compressor-driven refrigerators
and electric power tools
.Other equipment requiring an extremely
stable power supply, such as
microcomputer-controlled electric blankets
and touch sensor lamps
.Medical equipment
Cigarette Lighter
If equipped with a cigarette lighter, to heat,
push it in all the way and let go. When it is
ready for use, it will pop back out by itself.
Do not use the lighter to plug in accessory
devices. Use the power outlets provided.
Caution
Holding a cigarette lighter in while it is
heating does not let the lighter back
away from the heating element when it
is hot. Damage from overheating can
occur to the lighter or heating element,
or a fuse could be blown. Do not hold a
cigarette lighter in while it is heating.
Ashtrays
If equipped with a removable ashtray, it can
be placed into the front floor console
cupholder. Open the cover to use.
Caution
If papers, pins, or other flammable items
are put in the ashtray, hot cigarettes or
other smoking materials could ignite
(Continued)
Caution (Continued)
them and possibly damage the vehicle.
Never put flammable items in the
ashtray.
Warning Lights, Gauges, and
Indicators
Warning lights and gauges can signal that
something is wrong before it becomes
serious enough to cause an expensive repair
or replacement. Paying attention to the
warning lights and gauges could prevent
injury.
Some warning lights come on briefly when
the engine is started to indicate they are
working. When one of the warning lights
comes on and stays on while driving,
or when one of the gauges shows there
may be a problem, check the section that
explains what to do. Waiting to do repairs
can be costly and even dangerous.

Chevrolet Express Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
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74 Instruments and Controls
Caution
Lack of proper engine oil maintenance
can damage the engine. Driving with the
engine oil low can also damage the
engine. The repairs would not be covered
by the vehicle warranty. Check the oil
level as soon as possible. Add oil if
required, but if the oil level is within the
operating range and the oil pressure is
still low, have the vehicle serviced.
Always follow the maintenance schedule
for changing engine oil.
Engine Coolant Temperature
Gauge
Metric
EnglishThis gauge shows the engine coolant
temperature.
It also provides an indicator of how hard the
vehicle is working. During a majority of the
operation, the gauge will read 100 °C (210 °F)
or less. If the vehicle is pulling a load or
going up hills, it is normal for the
temperature to fluctuate and approach the
122 °C (250 °F) mark. If the gauge reaches
the 125 °C (260 °F) mark, it indicates that the
cooling system is working beyond its
capacity.
See
Engine Overheating 0187.
Voltmeter Gauge

Chevrolet Express Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
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Driving and Operating 125
{Warning
Using the brakes to slow the vehicle on a
long downhill slope can cause brake
overheating, can reduce brake
performance, and could result in a loss of
braking. Shift the transmission to a lower
gear to let the engine assist the brakes
on a steep downhill slope.
{Warning
Coasting downhill in N (Neutral) or with
the ignition off is dangerous. This can
cause overheating of the brakes and loss
of steering assist. Always have the engine
running and the vehicle in gear.
.Drive at speeds that keep the vehicle in
its own lane. Do not swing wide or cross
the center line.
.Be alert on top of hills; something could
be in your lane (e.g., stalled car, crash).
.Pay attention to special road signs (e.g.,
falling rocks area, winding roads, long
grades, passing or no-passing zones) and
take appropriate action.
Winter Driving
Driving on Snow or IceCaution
To avoid damage to the wheels and
brake components, always clear snow and
ice from inside the wheels and
underneath the vehicle before driving.
Snow or ice between the tires and the road
creates less traction or grip, so drive
carefully. Wet ice can occur at about 0 °C
(32 °F) when freezing rain begins to fall.
Avoid driving on wet ice or in freezing rain
until roads can be treated.
For Slippery Road Driving:
.Accelerate gently. Accelerating too quickly
causes the wheels to spin and makes the
surface under the tires slick.
.Turn on Traction Control. See Traction
Control/Electronic Stability Control 0142.
.The Antilock Brake System (ABS) improves
vehicle stability during hard stops, but
the brakes should be applied sooner than
when on dry pavement. See Antilock
Brake System (ABS) 0141.
.Allow greater following distance and
watch for slippery spots. Icy patches can
occur on otherwise clear roads in shaded
areas. The surface of a curve or an
overpass can remain icy when the
surrounding roads are clear. Avoid sudden
steering maneuvers and braking while
on ice.
.Turn off cruise control.
Blizzard Conditions
Stop the vehicle in a safe place and signal
for help. Stay with the vehicle unless there
is help nearby. To get help and keep
everyone in the vehicle safe:
.Turn on the hazard warning flashers.
.Tie a red cloth to an outside mirror.
{Warning
Snow can trap engine exhaust under the
vehicle. This may cause exhaust gases to
get inside. Engine exhaust contains
carbon monoxide (CO), which cannot be
seen or smelled. It can cause
unconsciousness and even death.
(Continued)

Chevrolet Express Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
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134 Driving and Operating
Warning (Continued)
personal injury may result. Always park
the vehicle in a clear open area away
from buildings or structures.
The engine coolant heater can provide easier
starting and better fuel economy during
engine warm-up in cold weather conditions
at or below −18 °C (0 °F). Vehicles with an
engine coolant heater should be plugged in
at least four hours before starting.
An internal thermostat in the plug end of
the cord may exist which will prevent
engine coolant heater operation at
temperatures above −18 °C (0 °F).
To Use the Engine Coolant Heater
1. Turn off the engine.
2. Open the hood and unwrap the
electrical cord.
The cord for the engine coolant heater is
on the driver side of the engine
compartment.
Check the heater cord for damage. If it is
damaged, do not use it. See your dealer
for a replacement. Inspect the cord for
damage yearly.
3. Plug it into a normal, grounded 110-volt AC outlet.
{Warning
Improper use of the heater cord or an
extension cord can damage the cord and
may result in overheating and fire.
.Plug the cord into a three-prong
electrical utility receptacle that is
protected by a ground fault detection
function. An ungrounded outlet could
cause an electric shock.
.Use a weatherproof, heavy-duty,
15 amp-rated extension cord if needed.
Failure to use the recommended
extension cord in good operating
condition, or using a damaged heater
(Continued)

Chevrolet Express Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
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158 Driving and Operating
Make wider turns than normal when towing,
so 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, seeEngine
Overheating 0187.
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)

Chevrolet Express Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
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Driving and Operating 159
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. 5. Reapply the brake pedal. Then apply the
parking 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 0245. 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 0187.
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.

Chevrolet Express Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
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172 Vehicle Care
Vehicle Care
General Information
General Information . . . . . . . . . . . . . . . . . . . 173
California Perchlorate MaterialsRequirements . . . . . . . . . . . . . . . . . . . . . . . . 173
Accessories and Modifications . . . . . . . . . . 173
Vehicle Checks
Doing Your Own Service Work . . . . . . . . . 173
Hood . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 174
Engine Compartment Overview . . . . . . . . 176
Engine Oil . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 179
Engine Oil Life System . . . . . . . . . . . . . . . . . 181
Automatic Transmission Fluid . . . . . . . . . . 181
Engine Air Cleaner/Filter . . . . . . . . . . . . . . . 182
Cooling System . . . . . . . . . . . . . . . . . . . . . . . . 183
Engine Overheating . . . . . . . . . . . . . . . . . . . . 187
Engine Fan . . . . . . . . . . . . . . . . . . . . . . . . . . . . 188
Power Steering Fluid . . . . . . . . . . . . . . . . . . 188
Washer Fluid . . . . . . . . . . . . . . . . . . . . . . . . . . 189
Brakes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 189
Brake Fluid . . . . . . . . . . . . . . . . . . . . . . . . . . . . 190
Battery - North America . . . . . . . . . . . . . . . 191
Rear Axle . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 192
Noise Control System . . . . . . . . . . . . . . . . . . 192
Starter Switch Check . . . . . . . . . . . . . . . . . . . 193
Automatic Transmission Shift Lock Control Function Check . . . . . . . . . . . . . . 193
Ignition Transmission Lock Check . . . . . . 193 Park Brake and P (Park) Mechanism
Check . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 193
Wiper Blade Replacement . . . . . . . . . . . . . 194
Windshield Replacement . . . . . . . . . . . . . . 194
Headlamp Aiming
Front Headlamp Aiming . . . . . . . . . . . . . . . 194
Bulb Replacement
Bulb Replacement . . . . . . . . . . . . . . . . . . . . . 195
Halogen Bulbs . . . . . . . . . . . . . . . . . . . . . . . . . 195
Front Turn Signal, Sidemarker, and Parking Lamps . . . . . . . . . . . . . . . . . . . . . . . 195
Taillamps . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 195
Center High-Mounted Stoplamp (CHMSL) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 196
License Plate Lamp . . . . . . . . . . . . . . . . . . . . 197
Electrical System
Electrical System Overload . . . . . . . . . . . . . 197
Fuses and Circuit Breakers . . . . . . . . . . . . . 198
Engine Compartment Fuse Block . . . . . . 199
Floor Console Fuse Block . . . . . . . . . . . . . . 202
Wheels and Tires
Tires . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 204
All-Season Tires . . . . . . . . . . . . . . . . . . . . . . . 204
Winter Tires . . . . . . . . . . . . . . . . . . . . . . . . . . . 205
Tire Sidewall Labeling . . . . . . . . . . . . . . . . . 205
Tire Designations . . . . . . . . . . . . . . . . . . . . . . 207
Tire Terminology and Definitions . . . . . 208
Tire Pressure . . . . . . . . . . . . . . . . . . . . . . . . . . 210 Tire Pressure Monitor System . . . . . . . . . . 211
Tire Pressure Monitor Operation . . . . . . . 212
Tire Inspection . . . . . . . . . . . . . . . . . . . . . . . . . 214
Tire Rotation . . . . . . . . . . . . . . . . . . . . . . . . . . 214
When It Is Time for New Tires . . . . . . . . 216
Buying New Tires . . . . . . . . . . . . . . . . . . . . . . 217
Different Size Tires and Wheels . . . . . . . . 218
Uniform Tire Quality Grading . . . . . . . . . . 218
Wheel Alignment and Tire Balance . . . . 219
Wheel Replacement . . . . . . . . . . . . . . . . . . . 220
Tire Chains . . . . . . . . . . . . . . . . . . . . . . . . . . . . 220
If a Tire Goes Flat . . . . . . . . . . . . . . . . . . . . . 221
Tire Changing . . . . . . . . . . . . . . . . . . . . . . . . . 222
Full-Size Spare Tire . . . . . . . . . . . . . . . . . . . . 230
Jump Starting
Jump Starting - North America . . . . . . . . 230
Towing the Vehicle
Towing the Vehicle . . . . . . . . . . . . . . . . . . . . 233
Recreational Vehicle Towing . . . . . . . . . . . 234
Appearance Care
Exterior Care . . . . . . . . . . . . . . . . . . . . . . . . . . 235
Interior Care . . . . . . . . . . . . . . . . . . . . . . . . . . . 239
Floor Mats . . . . . . . . . . . . . . . . . . . . . . . . . . . . 242

Chevrolet Express Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
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184 Vehicle Care
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 0187.
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)
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.

Chevrolet Express Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
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Vehicle Care 187
7. By this time, the coolant level inside theradiator filler neck may be lower. If the
level is lower, add more of the proper
mixture through the filler neck until the
level reaches the base of the filler neck.
8. Replace the pressure cap. At any time during this procedure if coolant begins to
flow out of the filler neck, reinstall the
pressure cap.
Caution
If the pressure cap is not tightly installed,
coolant loss and engine damage may
occur. Be sure the cap is properly and
tightly secured.
Engine Overheating
If the vehicle has a diesel engine, see the
Duramax diesel supplement.
Caution
Do not run the engine if there is a leak
in the engine cooling system. This can
cause a loss of all coolant and can
damage the system and vehicle. Have
any leaks fixed right away. The vehicle has an indicator to warn of
engine overheating.
There is an engine coolant temperature
gauge on the vehicle's instrument cluster.
See
Engine Coolant Temperature Gauge
0 74.
If the decision is made not to lift the hood
when this warning appears, but instead get
service help right away, see Roadside
Assistance Program 0262.
If the decision is made to lift the hood,
make sure the vehicle is parked on a level
surface.
Then check to see if the engine cooling fans
are running. If the engine is overheating, the
fan should be running. If it is not, do not
continue to run the engine and have the
vehicle serviced.
See if the engine cooling fan speed increases
when idle speed is doubled by pushing the
accelerator pedal down. If it does not, the
vehicle needs service. Turn off the engine.
If Steam is Coming from the Engine
Compartment
{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,
including the pressure cap, is hot. Wait
for the cooling system and pressure cap
to cool.
If No Steam is Coming from the Engine
Compartment
If an engine overheat warning is displayed
but no steam can be seen or heard, the
problem may not be too serious. Sometimes
the engine can get a little too hot when the
vehicle:
.Climbs a long hill on a hot day.
.Stops after high-speed driving.
.Idles for long periods in traffic.
.Tows a trailer. See “Driving on Grades”
under Trailer Towing 0159.

Chevrolet Express Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
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204 Vehicle Care
Circuit Breakers UsageCB1 Power Seats
CB2 Power Windows
Wheels and Tires
Tires
Every new GM vehicle has high-quality
tires made by a leading tire
manufacturer. See the warranty manual
for information regarding the tire
warranty and where to get service. For
additional information refer to the tire
manufacturer.
{Warning
.Poorly maintained and improperly
used tires are dangerous.
.Overloading the tires can cause
overheating as a result of too
much flexing. There could be a
blowout and a serious crash. See
Vehicle Load Limits 0126.
(Continued)
Warning (Continued)
.Underinflated tires pose the same
danger as overloaded tires. The
resulting crash could cause serious
injury. Check all tires frequently to
maintain the recommended
pressure. Tire pressure should be
checked when the tires are cold.
.Overinflated tires are more likely
to be cut, punctured, or broken by
a sudden impact —such as when
hitting a pothole. Keep tires at the
recommended pressure.
.Worn or old tires can cause a
crash. If the tread is badly worn,
replace them.
.Replace any tires that have been
damaged by impacts with
potholes, curbs, etc.
.Improperly repaired tires can cause
a crash. Only your dealer or an
authorized tire service center
should repair, replace, dismount,
and mount the tires.
(Continued)
Warning (Continued)
.Do not spin the tires in excess of
56 km/h (35 mph) on slippery
surfaces such as snow, mud, ice,
etc. Excessive spinning may cause
the tires to explode.
All-Season Tires
This vehicle may come with all-season tires.
These tires are designed to provide good
overall performance on most road surfaces
and weather conditions. Original equipment
tires designed to GM's specific tire
performance criteria have a TPC specification
code molded onto the sidewall. Original
equipment all-season tires can be identified
by the last two characters of this TPC code,
which will be “MS.”
Consider installing winter tires on the
vehicle if frequent driving on snow or
ice-covered roads is expected. All-season tires
provide adequate performance for most
winter driving conditions, but they may not
offer the same level of traction or
performance as winter tires on snow or
ice-covered roads. See Winter Tires0205.