2018 CHEVROLET EXPRESS engine overheat

Chevrolet Express Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
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Vehicle Care 213
Vehicle Care
General Information
General Information . . . . . . . . . . 214
California Proposition65 Warning . . . . . . . . . . . . . . . . . 214
California Perchlorate Materials Requirements . . . . . 215
Accessories and Modifications . . . . . . . . . . . . . . . . 215
Vehicle Checks
Doing Your OwnService Work . . . . . . . . . . . . . . . 215
Hood . . . . . . . . . . . . . . . . . . . . . . . . . 216
Engine Compartment Overview . . . . . . . . . . . . . . . . . . . . 217
Engine Oil . . . . . . . . . . . . . . . . . . . . 220
Engine Oil Life System . . . . . . . 222
Automatic Transmission Fluid (6-Speed Transmission) . . . . . 223
Automatic Transmission Fluid (8-Speed Transmission) . . . . . 226
Engine Air Cleaner/Filter . . . . . . 227
Cooling System . . . . . . . . . . . . . . 229
Engine Overheating . . . . . . . . . . 233
Engine Fan . . . . . . . . . . . . . . . . . . . 234
Power Steering Fluid . . . . . . . . . 235
Washer Fluid . . . . . . . . . . . . . . . . . 235 Brakes . . . . . . . . . . . . . . . . . . . . . . . 236
Brake Fluid . . . . . . . . . . . . . . . . . . . 237
Battery - North America . . . . . . 238
Rear Axle . . . . . . . . . . . . . . . . . . . . 239
Noise Control System . . . . . . . . 240
Starter Switch Check . . . . . . . . . 241
Automatic Transmission Shift
Lock Control Function
Check . . . . . . . . . . . . . . . . . . . . . . . 241
Ignition Transmission Lock Check . . . . . . . . . . . . . . . . . . . . . . . 242
Park Brake and P (Park) Mechanism Check . . . . . . . . . . 242
Wiper Blade Replacement . . . . 242
Gas Strut(s) . . . . . . . . . . . . . . . . . . 243
Headlamp Aiming
Headlamp Aiming . . . . . . . . . . . . 244
Bulb Replacement
Bulb Replacement . . . . . . . . . . . . 244
Halogen Bulbs . . . . . . . . . . . . . . . . 244
Front Turn Signal, Sidemarker, and Parking Lamps . . . . . . . . . 245
Taillamps . . . . . . . . . . . . . . . . . . . . . 245
Center High-Mounted Stoplamp (CHMSL) . . . . . . . . . 246
License Plate Lamp . . . . . . . . . . 247
Electrical System
Electrical System Overload . . . 248 Fuses and Circuit Breakers . . . 248
Engine Compartment Fuse
Block . . . . . . . . . . . . . . . . . . . . . . . . 248
Floor Console Fuse Block . . . . 253
Wheels and Tires
Tires . . . . . . . . . . . . . . . . . . . . . . . . . . 255
All-Season Tires . . . . . . . . . . . . . . 256
Winter Tires . . . . . . . . . . . . . . . . . . 256
All-Terrain 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 . . . . . . . . . . . . . . . . . . . . . . 273
Uniform Tire Quality Grading . . . . . . . . . . . . . . . . . . . . . 273
Wheel Alignment and Tire Balance . . . . . . . . . . . . . . . . . . . . . 275

Chevrolet Express Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
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Vehicle Care 223
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)
0111.
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)
0111.
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

Chevrolet Express Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
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224 Vehicle Care
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 inMaintenance
Schedule 0303, and be sure to use
the transmission fluid listed in
Recommended Fluids and
Lubricants 0310.
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

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Vehicle Care 229
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 (Outof View)
6.0L V8 Engine
1. Radiator Pressure Cap
2. Coolant Recovery Tank
3. Engine Cooling Fan (Outof 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,
see Engine Overheating 0233.

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What to Use
{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.
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.

Chevrolet Express Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
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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.
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,
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.

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Vehicle Care 233
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 0101.
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 0322.
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.

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234 Vehicle Care
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” underTrailer Towing
0 205.
If the overheat warning is displayed
with no sign of steam: 1. Turn the air conditioning off.
2. Turn the heater on to the highest temperature and to the
highest fan speed. Open the
windows as necessary.
3. When it is safe to do so, pull off the road, shift to P (Park) or
N (Neutral) and let the
engine idle. If the engine coolant temperature
gauge is no longer in the overheat
zone or an overheat warning no
longer displays, the vehicle can be
driven. Continue to drive the vehicle
slowly for about 10 minutes. Keep a
safe vehicle distance from the
vehicle in front. If the warning does
not come back on, continue to drive
normally and have the cooling
system checked for proper fill and
function.
If the warning continues, pull over,
stop, and park the vehicle
right away.
If there is still no sign of steam,
push down the accelerator until the
engine speed is about twice as fast
as normal idle speed for at least
three minutes while parked. If the
warning is still on, turn off the
engine until it cools down.
If the decision is made not to lift the
hood, get service help right away.
Engine Fan
The vehicle has a clutched engine
cooling fan. When the clutch is
engaged, the fan spins faster to
provide more air to cool the engine.
In most everyday driving conditions,
the fan is spinning slower and the
clutch is not fully engaged. This
improves fuel economy and reduces
fan noise. Under heavy vehicle
loading, trailer towing, and/or high
outside temperatures, the fan speed
increases as the clutch more fully
engages, so an increase in fan
noise may be heard. This is normal
and should not be mistaken as the
transmission slipping or making
extra shifts. It is merely the cooling
system functioning properly. The fan
will slow down when additional
cooling is not required and the
clutch partially disengages.
This fan noise may be heard when
starting the engine. It will go away
as the fan clutch partially
disengages.