engine overheat CHEVROLET LOW CAB FORWARD 2017 User Guide

Chevrolet Low Cab Forward Owner Manual (GMNA-Localizing-U.S.-
10716700) - 2017 - crc - 12/6/16
Driving and Operating 139
Caution (Continued)
warning light comes on during
operation, have brake system
checked immediately.
Refer to Warning Lights, Gauges,
and Indicators 076.
When the Brakes Do Not Work
{Warning
It is very dangerous to suddenly
pull the parking brake lever all the
way while moving at high speed.
Reduce speed first by shifting
down and then gradually pull the
parking brake lever.
You and others could be seriously
injured.
(Diesel Only) The exhaust brake
should be turned on as soon as
service brake malfunction is
detected. This will slow the engine
speed. With the engine speed under
control and providing the grade conditions permit, the transmission
can be progressively downshifted
using the exhaust brake in each
gear. Eventually the exhaust brake
should slow the vehicle to a
controllable
“crawl.”Gradually pull
the parking brake lever while firmly
holding on to the steering wheel.
Stop the vehicle on the side of the
road. The vehicle should not be
driven further until corrective
measures are taken.
See Exhaust Brake (Diesel Only)
0 222 andParking Brake 0221.
(Gasoline Only) If the brakes do not
work in an unexpected situation,
promptly shift down from D6, D4,
2nd and then to 1st gear using the
selector lever to reduce the speed
and gradually pull the parking brake
lever to stop the vehicle on the side
of the road while firmly holding on to
the steering wheel.
See Parking Brake 0221. Riding the Brake
{Warning
"Riding the brake" by resting your
foot on the pedal, when you do
not intend to brake, can overheat
the brakes and wear out the
brake linings faster. This may also
damage the brakes and will waste
fuel. It can also result in reduced
braking performance.
You and others could be seriously
injured.
Applying the Parking Brake
Except in an emergency, do not
apply the parking brake until the
vehicle has come to a complete
stop. Applying the parking brake
before the vehicle has stopped can
cause a breakdown.
Refer to
Parking Brake 0221.
Parking Safely on a Slope
Avoid parking your vehicle on a
slope as much as possible and
choose a level and flat place. If you

Chevrolet Low Cab Forward Owner Manual (GMNA-Localizing-U.S.-
10716700) - 2017 - crc - 12/6/16
140 Driving and Operating
must park your vehicle on a slope,
be sure to set the parking brake
fully. Make sure that the vehicle
does not move, and block the
wheels with chocks for added
safety. Also, leave the vehicle in
gear to further ensure that it will not
move. Leave the steering wheel
turned such that the vehicle will be
stopped by an obstruction (for
example, the curb) in the unlikely
event that it moves.
Stopping and Parking with the
Engine Running
{Warning
When parking with the engine
running, first come to a complete
stop, then firmly apply the parking
brake, then move the selector
lever to the "P" (Park) position.
Unless you take these steps, any
unintended pressure on the
accelerator pedal could cause an
accident.(Continued)
Warning (Continued)
To reduce the chance of personal
injury and/or vehicle damage due
to engine overheating, never
leave the engine idling without an
alert driver present. If the engine
should overheat, as indicated by
the engine coolant temperature
gauge, immediate action is
required to correct the condition.
Continued operation of the
engine, even for a short time, may
result in a fire. Do not engage the
exhaust brake while the engine is
idling as this may cause engine
overheating.
The diesel particulate filter (DPF)
may automatically start
regeneration when the vehicle is
stopped and parked with the
engine running. To prevent a fire,
make sure there is no flammable
material near the muffler, DPF,
and exhaust pipe. Be careful not
to get burned by hot exhaust
gases.(Continued)
Warning (Continued)
You and others could be seriously
injured.
Do Not Forget to Release the
Parking Brake
Pulling away with the parking brake
still applied can damage the brake
system.
Before pulling away, make sure the
parking brake is not set by checking
that the parking brake indicator light
is not on.
Be Sure to Have the Engine
Running When the Vehicle is
Moving
{Warning
When the engine is not running,
the power steering system does
not work so the steering wheel is
hard to turn. Also, the brake
booster does not work so there is
little braking ability. If you coast (Continued)

Chevrolet Low Cab Forward Owner Manual (GMNA-Localizing-U.S.-
10716700) - 2017 - crc - 12/6/16
142 Driving and Operating
Frequent use of the foot brakes can
cause vapor lock and brake fade,
resulting in reduced brake
effectiveness.
Brake Fade :Frequent use of the
brakes can cause the brakes to
overheat so that the frictional force
of the brake linings decreases and
the brakes become less effective
than normal. This phenomenon is
called brake fade.
Vapor Lock : If the brakes overheat
due to frequent use, the heat can
cause the brake fluid to boil so that
air bubbles are created in the brake
fluid. Pressing the brake pedal
simply compresses the air bubbles;
pressure is not transmitted to the
wheel cylinders, so the brakes'
effectiveness sharply deteriorates.
This phenomenon is called
vapor lock.
Even so, you should be very careful
when using engine braking in a low
gear because the engine is likely to
over-rev.
See Exhaust Brake (Diesel Only)
0 222 andSelector Lever 0214. On diesel vehicles, do not adjust the
exhaust brake valve.
The engine should never be allowed
to exceed the governed speed.
Supplement the exhaust brake with
vehicle service brakes intermittently
and/or shift to higher transmission
gear to prevent engine overspeed.
A rule of thumb for gear selection is
that the vehicle should be driven
down a grade in the same gear that
would be used to climb that grade.
{Warning
To reduce the risk of personal
injury, before going down a steep
or long grade, reduce speed, turn
on the exhaust brake and shift the
transmission to the next lower
gear. This will help control your
speed. Do not hold the brake
pedal down too long or too often
while going down a steep or long
grade. This could cause the
brakes to get hot and not to work
as well. As a result, the truck will
(Continued)
Warning (Continued)
not slow down at the usual rate.
Failure to take these steps could
result in loss of vehicle control.
You and others could be seriously
injured.
Brake Effectiveness When the
Vehicle Has Been Driven on a
Flooded Road or Washed
{Warning
When the vehicle is driven on a
flooded road, parked on a flooded
road or washed, water can get
into the brakes and reduce their
effectiveness. If the brakes do not
work well afterward, drive slowly
and gently press the brake pedal
several times until the brakes dry
out and start working normally.
Always do this after driving
through water or washing the
vehicle to help reduce the risk of(Continued)

Chevrolet Low Cab Forward Owner Manual (GMNA-Localizing-U.S.-
10716700) - 2017 - crc - 12/6/16
Driving and Operating 155
SymptomCauseCorrective Action Reference
Black exhaust smoke (Diesel) Engine Control system
faulty
4-
The air cleaner clogged
4-
Fuel system faulty
4-
Exhaust system clogged
4-
Exhaust injector
4-
Diesel particulate filter
(DPF) faulty
4-
Engine is overheating No engine coolant Add engine coolant
See
Engine
Coolant 0263
Front of radiator is
clogged with dirt Wash clean with tap
waterSee
Exterior Care
0 334
Radiator cap not
sufficiently tightened Make sure it is firmly
tightened or replace the
radiator cap
-
Fan belt loose Adjust the tension or
replace the beltSee
Engine Drive
Belt Routing 0396
Engine coolant dirty
4-
Fan clutch is faulty
4-
Radiator cap dirty or
faulty Clean or replace -

Chevrolet Low Cab Forward Owner Manual (GMNA-Localizing-U.S.-
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166 Driving and Operating
engine is running. If it stays on,
shut the engine off and find the
cause.
2. Look at the engine coolant temperature gauge. If the
gauge reaches the H (HOT)
area, stop the engine and find
the cause of the overheating.
3. Check that the battery warning light has gone out. The light
should go off and stay off at
normal idle speeds. If the light
does not go out or comes on
during normal operation, have
the charging system checked.
4. Check that the brake low vacuum warning light is out
and that the vacuum buzzer is
not sounding. It is normal for
the warning buzzer to sound
for a few seconds after the
engine starts. If the light and
buzzer remain on, do not drive
the vehicle until the cause has
been found and corrected.
5. Look at the brake system warning light. It should be out
when the parking brake is
released and the engine is running. If it stays on, it could
mean that the brake fluid level
is low. Check the brake fluid
reservoir. This condition must
be corrected before moving the
vehicle.
Caution
To reduce the chance of personal
injury and/or vehicle damage due
to engine overheating, never
leave the engine idling without an
alert driver present. If the engine
should overheat, as indicated by
the engine coolant temperature
gauge, immediate action is
required to correct the condition.
Continued operation of the
engine, even for a short time, may
result in a fire.
Starting the Engine
Do not keep the engine control
switch in the START position for
more than about 10 seconds.
Operating the starter for too long
might cause starter and battery
failure or may result in overheating. When the engine does not start,
wait for 20 to 30 seconds and then
turn the engine control switch again.
Before starting the engine sit in the
driver seat, check that the parking
brake is firmly engaged, the selector
lever is in the P or N (P is preferred)
position and the shift indicator also
shows P or N, and firmly press the
brake pedal to start the engine. See
Ignition Positions
0163.
{Warning
Do not keep the starter motor
engaged for more than
10 seconds at a time, or the
starter motor and the battery will
be adversely affected. Also, fire
may occur due to overheating.
Repeat the steps after a 20 to
30 seconds break.
1. Shift your selector lever to P (Park) or N (Neutral). Your
engine will not start in any
other position-that's a safety

Chevrolet Low Cab Forward Owner Manual (GMNA-Localizing-U.S.-
10716700) - 2017 - crc - 12/6/16
Driving and Operating 169
Sit behind the wheel, adjust the seat
position, and buckle up the seat
belt. The passengers are also
required to buckle up the seat belts.
Adjust the positions of the steering
wheel and mirrors. Lock the doors.
Turn the power of the dome light or
accessories OFF before starting the
engine. SeeSeat Position 044,
Seat Belts 049, Steering Wheel
Adjustment 072, and Mirrors039.
Keep the Floor Around the
Driver's Seat Clean and Tidy
{Warning
It is extremely dangerous to have
empty cans, empty bottles or
other items rolling around on the
floor because they could get
trapped under the brake pedal
and prevent brake application.
For proper pedal operation, it is
also essential to lay floor mats
properly. Incorrectly installed floor
mats would hinder free movement
of the pedals. (Continued)
Warning (Continued)
Do not use the dashboard pocket
or the top of the dashboard as a
place to put items that could roll,
which could interfere with your
driving. You and others could be
seriously injured.
Choose Your Footwear Suitable
for Driving
{Warning
Choose footwear that ensures
proper operation of pedals when
driving the vehicle. Use of
footwear unsuitable for driving
may cause an accident.
Starting the Engine
Do not keep the engine control
switch in the START position for
more than about 10 seconds.
Operating the starter for too long
might cause starter and battery
failure or may result in overheating. When the engine does not start,
wait for 20 to 30 seconds and then
turn the engine control switch again.
Before starting the engine sit in the
driver seat, check that the parking
brake is firmly engaged, the selector
lever is in the P or N (P is preferred)
position and the shift indicator also
shows P or N, and firmly press the
brake pedal to start the engine.
When stopped on a slope, start the
engine with the selector lever in the
P position. See
Ignition Positions
0 163.
1. Make sure that the selector lever is in the P or N position
and firmly press the brake
pedal.
2. When the engine control switchis turned to the ON position,
the wait-to-start light comes on
and it goes out in about

Chevrolet Low Cab Forward Owner Manual (GMNA-Localizing-U.S.-
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Driving and Operating 173
.If you allow the engine to warm
up but the engine coolant
temperature does not rise, have
the nearest dealer inspect the
thermostat.
Radiator Grille Covers
{Warning
Radiator shutters, winter fronts,
or grille covers are not to be used
and may cause the engine's
radiator cooling fan to fatigue
from the alternate unloading and
loading of the blades as they
pass by the masked area
followed by the unmasked area.
After the fan has been fatigued, it
may suddenly break apart while
rotating, possibly causing
personal injury to anyone
standing nearby, and equipment
damage. You and others could be
seriously injured.
Engine Heater
Engine Block and Oil Pan Heater
If the vehicle is parked in a garage,
the block and pan heaters should
not be needed until the garage
temperature drops below −23°C
(−10°F) regardless of outside
temperature.
The engine block and oil pan
heaters are designed to warm the
block and oil pan areas that will let
the engine run faster. To use the
heaters:
1. On single cab vehicles, tilt the cab.
2. Unwrap the electrical cord and remove the protective cap.
3. Plug the cord into any three-prong 110 volt outlet
(normal household current).
It may require several hours to
sufficiently heat the engine.
Outside temperature, oil
viscosity, etc., will affect how
long the block and oil pan
heater should remain plugged
in. Contact your dealer for the
conditions in your area. 4. After using the heater(s), be
sure to restore the cord
properly, to help keep it away
from moving engine parts.
If the cord is too short, use a heavy
duty, three-prong extension cord. Do
not use an extension cord such as
you would use for a lamp, because
the cord may overheat.
The engine should go through a
warm-up period to warm up the
engine oil before placing engine
under load. This will ensure proper
lubrication of the engine. See Cab
Tilting 0247.

Chevrolet Low Cab Forward Owner Manual (GMNA-Localizing-U.S.-
10716700) - 2017 - crc - 12/6/16
Driving and Operating 175
Activating High Idle Mode
Follow the below procedure to
activate the high idle mode:1. Set the parking brake.
2. Set the selector lever in P (Park) or N (Neutral) position.
3. Do not press the brake pedal. 4. Press the cruise control main
switch to set it to ON. At this
time, the operation indicating
light will turn to green.
5. Turn and hold the cruise control set switch in the SET
position. After approximately
3 seconds the cruise control
set indicator light will begin to
flash slowly and the engine idle
will increase to 1,200 r/min.
Canceling High Idle Mode
Any of the following actions will
cancel high idle mode.
. The cruise control main switch is
set to OFF.
. The brake pedal is pressed.
. The parking brake is released.
. The selector lever is moved from
P (Park) or N (Neutral) position.
. The accelerator pedal is
pressed, accelerating the engine
beyond the engine speed
threshold.
The cruise set indicator light will
stop flashing and the engine speed
will return to normal.
Engine Checks Before
Operating
Checks Before Operating
Allow the engine to warm up before
placing the engine under heavy load
driving. While the engine is warming
up under light load, the following
checks should be made:
1. Observe the red engine oil pressure warning light. The
light should go out when the
engine is running. If it stays on,
shut the engine off and find the
cause.
2. Look at the engine coolant temperature gauge. If the
gauge reaches the H (HOT)
area, stop the engine and find
the cause of the overheating.
3. Check that the battery warning light has gone out. The light
should go off and stay off at
normal idle speeds. If the light
does not go out or comes on
during normal operation, have
the charging system checked.

Chevrolet Low Cab Forward Owner Manual (GMNA-Localizing-U.S.-
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176 Driving and Operating
4. Check that the brake lowvacuum warning light is out
and that the vacuum buzzer is
not sounding. It is normal for
the warning buzzer to sound
for a few seconds after the
engine starts. If the light and
buzzer remain on, do not drive
the vehicle until the cause has
been found and corrected.
5. Look at the brake system warning light. It should be out
when the parking brake is
released and the engine is
running. If it stays on, it could
mean that the brake fluid level
is low. Check the brake fluid
reservoir. This condition must
be corrected before moving the
vehicle.
{Warning
To reduce the chance of personal
injury and/or vehicle damage due
to engine overheating, never
leave the engine idling without an
alert driver present. If the engine
(Continued)
Warning (Continued)
should overheat, as indicated by
the engine coolant temperature
gauge, immediate action is
required to correct the condition.
Continued operation of the
engine, even for a short time, may
result in a fire.
For vehicles with a diesel engine,
do not engage the exhaust brake
while the engine is idling as this
may cause engine overheating.
You and others could be seriously
injured.
Avoid Unnecessary Idling of the
Diesel Engine
If the diesel engine idles too long,
the engine coolant temperature will
fall below the operating range. Low
engine operating temperature
causes several conditions that are
harmful to engine operation and life.
Incomplete combustion of fuel in an
engine that is not fully warmed-up
causes crankcase dilution and
forms lacquer and gummy deposits on valves, pistons, and rings. It also
causes rapid accumulation of
sludge within the engine.
Parking over Things
That Burn
{Warning
Exhaust parts and gases become
very hot when the DPF is being
regenerated.
Parking over flammable items
could allow them to touch hot
exhaust parts under your vehicle
and cause them to ignite. Do not
park over papers, leaves, grass
or other things that can burn. You
and others could be seriously
injured.
Keep Flammable Material Away
from the Vehicle
The exhaust pipe is extremely hot
immediately after vehicle operation.
Before parking, make sure the area
is free of flammable material (for

Chevrolet Low Cab Forward Owner Manual (GMNA-Localizing-U.S.-
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Driving and Operating 179
Warning (Continued)
or corroded exhaust system or
cab. Do not run the engine in
confined areas (such as garages,
next to a building or near another
stopped vehicles with engine
running) any more than needed to
move the vehicle.
When the vehicle has to be
stopped in an unconfined area
with the engine running for any
more than a few minutes, take the
following steps:. Adjust the heating or cooling
system to force outside air
into the cab.
. With temperature and outlet
selector knob in any
position:
. Set the air selector lever to
the fresh air position.
. Set the fan speed control
knob to the maximum speed
position.
(Continued)
Warning (Continued)
.Keep the exhaust tailpipe
area clear of snow and
other material to help
reduce the buildup of
exhaust gases under the
vehicle.
This is particularly important when
parked in blizzard conditions. You
and others could be seriously
injured.
See Climate Control Systems 0126
and Maintenance Schedule 0345.
Running the Vehicle
While Parked
Caution
To reduce the chance of personal
injury and/or vehicle damage due
to engine overheating, never
leave the engine idling without an
alert driver present. If the engine
(Continued)
Caution (Continued)
should overheat, as indicated by
the engine coolant temperature
gauge, immediate action is
required to correct the condition.
Continued operation of the
engine, even for a short time, may
result in a fire. Do not engage the
exhaust brake while the engine is
idling as this may cause engine
overheating.
Avoid Unnecessary Idling of the
Diesel Engine
If the engine idles too long, the
engine coolant temperature will fall
below the operating range. Low
engine operating temperature
causes several conditions that are
harmful to engine operation and life.
Incomplete combustion of fuel in an
engine that is not fully warmed-up
causes crankcase dilution and
forms lacquer and gummy deposits
on valves, pistons, and rings. It also
causes rapid accumulation of
sludge within the engine.