Chevrolet Low Cab Forward Owner Manual (GMNA-Localizing-U.S.-
10716700) - 2017 - crc - 12/6/16
186 Driving and Operating
If you continue driving too long with
the selectable (switch) regeneration
required warning light (amber)
displayed on the DIC, the message
will change to red. The selectable
(switch) regeneration required
warning light (red) indicates the
DPF filter is nearly full of PM, a
condition which may be damaging
to the filter.
DPF regeneration should be
completed immediately if the
selectable (switch) regeneration
required warning light (red) is
displayed on the DIC.
Continued driving without
performing DPF regeneration will
cause the check engine malfunction
indicator light and reduced engine
power indicator light to come on, an
engine power reduction, and may
cause damage to the DPF filter. See
Driver Information Center (DIC)
(Diesel Only)093.
When operating the PTO for a long
time if your vehicle is so equipped,
make sure that the regeneration
required warning light or selectable (switch) regeneration required
warning light (amber) is not
turning on.
Once the Switch regeneration is
started, it cannot be switched to the
Running regeneration if interrupted.
When the Switch regeneration is
selected, end regeneration in a
single operation if possible.
During the regeneration, the engine
speed may vary, causing the
exhaust brake valve to be
deactivated. However, while the
regeneration in progress indicator
light (amber) appears, regeneration
is still taking place, so continue to
perform regeneration until the
message goes off.
The time needed to complete
regeneration differs depending on
the outside temperature.
The exhaust brake or exhaust
throttle is activated during DPF
regeneration. The exhaust brake or
exhaust throttle starting to operate
or being disengaged will produce a
sound, but this does not indicate a
failure.During regeneration, white smoke
may be temporarily produced from
the exhaust pipe. This results from
combustion of PM, it does not
indicate a failure.
Switch regeneration will complete
earlier immediately after driving than
when the engine is cold.
The engine coolant temperature
may rise during switch regeneration.
Interruption of Switch
Regeneration
If you must interrupt regeneration for
an unavoidable reason, press the
DPF switch again.
The regeneration in progress
indicator light (amber) changes to
the selectable (switch) regeneration
required warning light (amber).
Then, you can drive the vehicle.
If you interrupt regeneration, you
need to perform regeneration again.
Perform switch regeneration
beginning with Step 1 as soon as
possible.
Chevrolet Low Cab Forward Owner Manual (GMNA-Localizing-U.S.-
10716700) - 2017 - crc - 12/6/16
Driving and Operating 189
the selectable (switch) regeneration
required warning light (red) is
displayed on the DIC.
Continued driving without
performing DPF regeneration will
cause the check engine malfunction
indicator light and reduced engine
power indicator light to come on, an
engine power reduction, and may
cause damage to the DPF filter. See
Vehicle Messages (Diesel Only)
097.
The time needed to complete
regeneration differs depending on
the outside temperature.
The exhaust brake is activated
during DPF regeneration. The
exhaust brake starting to operate or
being disengaged will produce a
sound, but this does not indicate a
failure.
During regeneration, white smoke
may be temporarily produced from
the exhaust pipe. This results from
combustion of PM, it does not
indicate a failure. Regeneration is finished earlier
immediately after driving than when
the engine is cold.
The engine coolant temperature
may rise during regeneration.
DPF Regeneration during
Prolonged Idling
DPF regeneration may be initiated
automatically during prolonged
idling. If regeneration is initiated, the
regeneration in progress indicator
light (amber) comes on but this is
normal and does not indicate a
failure.
If driving is started or the PTO is
connected during DPF regeneration
by prolonged idling, the selectable
(switch) regeneration required
warning light (amber) comes on and
regeneration is suspended. Perform
Switch regeneration procedure in
order to complete the DPF
regeneration.
Prolonged idling may require more
frequent DPF regeneration.
See
Driver Information Center (DIC)
(Diesel Only) 093.Diesel Exhaust Fluid
Diesel exhaust fluid (DEF) is used
exclusively for the selective catalytic
reduction (SCR) system. Be sure to
use only API certified DEF. When
the SCR system detects DEF level
is nearly empty or incorrect fluids
(such as water or low concentrated
DEF.) are added, the SCR system
will turn on warning and indicator
lights and reduce engine power in
progressive stages to encourage
you to have the condition corrected.
Continuing to drive for too long after
these lights come on will eventually
result in a severe vehicle speed
limitation. See Vehicle Messages
(Diesel Only) 097
The DEF freezes below −11 °C (12 °
F). The SCR system is equipped
with a heating function which utilizes
the engine coolant, so the engine
can be started even when DEF is
frozen.
Chevrolet Low Cab Forward Owner Manual (GMNA-Localizing-U.S.-
10716700) - 2017 - crc - 12/6/16
192 Driving and Operating
Warning (Continued)
Do not add substances such as
gasoline or diesel fuel to the DEF
tank. You and others could be
seriously injured.
Caution
When opening the DEF tank cap,
be careful not to let dirt or other
foreign matter enter inside the
DEF tank. Intrusion of foreign
matter can cause a clogging of
the filter or affect the quality of
DEF, which may result in a SCR
system failure.
If DEF is spilled on the body or
frame, it may cause generation of
rust, so wipe it off and then rinse
it away with water.
When DEF dries it will leave a
crystalline residue, this condition is
normal. Wash with water or wipe
away the residue to prevent it from
entering the DEF tank. Adding DEF in Cold Weather
DEF freezes at low temperature but
the engine coolant circulates to
thaw the DEF tank and to prevent
DEF from freezing. Vehicle can be
driven normally when DEF is frozen.
If the refill diesel exhaust fluid (DEF)
warning light is on and the
remaining DEF in the DEF tank is
frozen, the warning lights, indicator
lights and restriction will not be
canceled until the DEF thaws even
if the DEF tank is refilled.
It is not recommended parking the
vehicle for long periods with the refill
diesel exhaust fluid (DEF) warning
light on in cold weather. The DEF
gauge will not register correctly
should the DEF freeze in this
condition causing the DEF low level
warning system not to reset when
DEF is added. Take the following
actions to avoid this condition in
cold weather:
1. Refill the DEF as soon as possible after parking the
vehicle. 2. Turn the engine control switch
to the ON position from the
LOCK position.
3. Wait for the warning buzzers and warning lights to turn off.
4. If the buzzer does not stop, return the engine control switch
back to the LOCK position and
add more DEF, and then start
over from step (2) above.
5. Turn the engine control switch to the LOCK position.
The DEF freezes at approximately
−11 °C (12 °F).
In cold weather, when the vehicle is
left without performing these actions
and the DEF tank freezes, the low
DEF level warnings and indicators
may not turn off when DEF is added
until after the tank defrosts.
Make sure to stop the engine before
adding the DEF. See Warning
Buzzers 0101.
When DEF Freezes
Engine coolant circulates through
the DEF tank to thaw it when frozen
and prevent it from freezing while
Chevrolet Low Cab Forward Owner Manual (GMNA-Localizing-U.S.-
10716700) - 2017 - crc - 12/6/16
Vehicle Care 263
.Diesel Engine Dipstick H
(HOT) —Transmission fluid
temperature Approx. 70 -
80 °C (158 - 176 °F).
. For diesel engines, the “C
(COLD)” range on the
dipstick is a guide used by
your dealer for specialized
equipment used to replace
or service the automatic
transmission fluid. When
performing your own
inspections, always use the
“H (HOT)” range after
warming up the vehicle.
The fluid must be hot to
ensure an accurate check.
The fluid level rises as
temperature increases.
6. If the fluid level is too low, add the specified fluid through the
dipstick guide tube. Also, check
whether there are no fluid
leaks.
7. Insert the dipstick securely into position.{Warning
Be extremely careful not to burn
yourself when checking the oil
level if the engine temperature is
high. Protect yourself with
gloves etc.
You and others could be seriously
injured.
Discarded parts, oil, grease and
fluids could have an adverse effect
on the environment. It is difficult to
dispose of these, so have your
dealer handle all checks and
replacements.
Engine Air Cleaner/Filter
Air Cleaner
Use of clogged air cleaner element
not only causes a deterioration in
the engine output but also increased
fuel consumption and dark exhaust
smoke. Be sure to use a genuine air cleaner
element. If other air cleaner element
is used, it may cause the sensor to
output a wrong signal.
See
Maintenance Schedule 0345.
Air Cleaner Indicator Light
(Diesel Vehicles Only)
When the air cleaner indicator light
comes on, check the air cleaner
element. If the air cleaner element is
clogged, replace the air cleaner
element.
See Vehicle Messages (Diesel
Only) 097.
See Maintenance Schedule 0345.
Engine Coolant
Protection of Engine against
Overcooling
Overcooling of the engine not only
accelerates wear of the vital engine
parts but also hurts fuel economy.
Chevrolet Low Cab Forward Owner Manual (GMNA-Localizing-U.S.-
10716700) - 2017 - crc - 12/6/16
Vehicle Care 265
Warning (Continued)
eyes are still irritated or otherwise
feel abnormal, seek immediate
medical attention.
If the engine coolant gets on your
skin, rinse it off using a soap with
a large amount of water. Also,
if abnormality is seen, seek
medical attention.
Engine coolant is flammable, and
therefore, it must be kept away
from flames and other heat
sources. Engine coolant also
could ignite if it comes in contact
with a hot surface, such as the
exhaust manifold. Exercise
caution to prevent this from
happening.
You and others could be seriously
injured.
Preparing Engine Coolant
To prevent engine damage due to
freezing of the engine coolant and
to protect the cooling system from
corrosion, use a mixture of the recommended type antifreeze and
water. If the engine of the vehicle is
at
−30 °C (−22 °F) or above, the
coolant concentration should be
50%. Direct use of “50/50
Pre-diluted” product which is already
diluted to 50% concentration is
recommended. If the outside
temperature engine or vehicle is
used at −30 °C (−22 °F) or below,
coolant concentration of 55% is
recommended.
It is the owner ’s responsibility to:
. Maintain the engine cooling
system freeze protection at or
above −30 °C (−22 °F) (at or
below −30 °C (−22 °F) in colder
climates to ensure protection
against corrosion and loss of
engine coolant from boiling.
A 50/50 (55/45 for colder
climates) mixture of the
recommended type antifreeze
and water will provide freeze
protection to at or above −30 °C
(−22 °F), (at or below −30 °C
(−22 °F) in colder climates) and
boil protection to 128 °C
(262 °F). Periodic replacement
of engine coolant is needed to replenish the anticorrosion
additives that wear out with use.
Engine coolant that has become
dark in color shows that it needs
to be changed.
. Use only the recommended
coolant. See Recommended
Fluids and Lubricants 0378.
. Do not use methanol-base
antifreeze, alcohol or plain water
alone in your vehicle at any time.
They will boil at a lower point
than that at which the engine
coolant temperature gauge will
warn of overheating, and they do
not provide proper protection
against corrosion.
Engine Coolant Quantity
For the quantity of engine coolant,
see Capacities and Specifications
0 389. After changing the engine
coolant, check that the engine
coolant is up to the specified level.
Chevrolet Low Cab Forward Owner Manual (GMNA-Localizing-U.S.-
10716700) - 2017 - crc - 12/6/16
Vehicle Care 269
2. Fill the radiator to the base ofthe filler neck (2).
.Add enough engine coolant
to provide the required
cooling, freezing and
corrosion protection.
. Install the radiator cap.
3. Run the engine until the engine coolant temperature rises to
normal level, and idle the
engine for 10 minutes.
4. Turn off the engine. Make sure that the engine is cool.
Remove the radiator cap and
add engine coolant to the
radiator until it reaches the
base of the filler neck.
5. Install the radiator cap.
Check, replenish or change the
engine coolant only after the engine
has sufficiently cooled down.
When the engine is still hot, take
care to prevent engine coolant from
contact with the exhaust manifold.
Any such contact could result in
exhaust manifold damage. If you use the proper quality engine
coolant, there is no need to add
extra inhibitors or additives which
claim to improve the system. They
may be harmful to the proper
operation of the system.
Do not overfill the engine coolant
reserve tank.
If the level of engine coolant
changes rapidly, have your vehicle
inspected at your dealer.
Thermostat
The engine coolant temperature is
controlled by thermostat(s). The
thermostats stop engine coolant
flow through the radiator until a
preset temperature is reached. The
thermostats are installed in the
engine coolant outlet on the engine
block. The same thermostats are
used in both winter and summer.
When a replacement is needed,
genuine GM parts are
recommended.
Radiator Pressure Cap
The radiator cap, a 103 kPa (15 psi)
pressure type for gasoline vehicles
and a 108 kPa (16 psi) for dieselvehicles, must be installed tightly,
otherwise engine coolant may be
lost and damage to the engine may
result from overheating. The radiator
pressure cap should be checked
periodically for proper operation. If a
replacement is required, a genuine
GM part is recommended.
Engine Overheating
When the Engine Overheats
The engine cooling system may
overheat if the engine coolant level
is too low, if there is a sudden loss
of engine coolant (such as radiator
hose failure), or if other problems
occur. It may also temporarily
overheat during severe operating
conditions such as:
.
Climbing a long hill on a hot day.
. Stopping after high-speed
driving.
. Idling for long periods in traffic.
If engine power drops and the
needle on the engine coolant
temperature gauge goes up above
the upper limit of the safety zone
and enters the "H" zone, the engine
Chevrolet Low Cab Forward Owner Manual (GMNA-Localizing-U.S.-
10716700) - 2017 - crc - 12/6/16
270 Vehicle Care
is overheating. The engine overheat
warning light will come on and on a
diesel vehicle, the warning buzzer
will sound. Either steam or boiling
engine coolant will squirt out of the
radiator. The diesel vehicle will also
have an“OVER HEAT” message
displayed. Take the following
corrective actions immediately.
{Warning
To help avoid being burned:
Do not tilt the cab or open the
engine access cover if you see or
hear steam or engine coolant
escaping from the engine
compartment. Wait until no steam
or engine coolant can be seen or
heard before tilting the cab or
opening the engine cover.
Do not remove the radiator cap or
engine coolant reserve tank cap if
the engine coolant in the tank is
boiling. Also do not remove the
radiator cap while the engine and
radiator are still hot. Scalding fluid
(Continued)
Warning (Continued)
and steam can be blown out
under pressure if either cap is
taken off too soon.
You and others could be seriously
injured.
If Steam is Coming from the
Engine Compartment
{Warning
If the engine coolant temperature
gauge shows an overheat
condition or you have other
reasons to suspect the engine
may be overheating, continued
operation of the engine (other
than as described here) even for
a short period of time may cause
a fire and the result in personal
injury and severe vehicle
damage. Take immediate action
as outlined.
You and others could be seriously
injured. If you see or hear escaping steam
or have any other reason to suspect
there is a serious overheat
condition, stop and park the vehicle
as soon as it is safe to do so, turn
on the hazard warning flasher and
then turn off the engine immediately
and safely exit the vehicle.
If Steam Is Not Coming from the
Engine Compartment
Chevrolet Low Cab Forward Owner Manual (GMNA-Localizing-U.S.-
10716700) - 2017 - crc - 12/6/16
Vehicle Care 271
For Diesel Vehicle
If the engine coolant temperature
gauge shows an overheat condition,
or you have reason to suspect the
engine may be overheating, take
the following steps: 1. Operate the hazard warning flasher and pull the vehicle
immediately over to a safe
place that does not impede
traffic and park it.
2. For the gasoline engine, if there's no sign of steam,
push the accelerator pedal until
the engine speed is about
twice as fast as normal idle
speed. Bring the engine speed back to normal idle after 2 or
3 minutes. Idle the engine and
wait until the engine coolant
temperature drops to safety
zone. If your air conditioner is
on, turn it off. And turn on the
heater to help the engine
expel heat.
For the diesel engine, idle the
engine and wait until the
engine coolant temperature
drops to safety zone. If your air
conditioner (if equipped) is on,
turn it off. And turn on the
heater to help the engine
expel heat.
3. When the needle of the engine coolant temperature gauge
returns to the middle of the
safety zone, stop the engine.
If the needle of engine coolant
temperature gauge does not
drop inside into the safety
zone, turn the engine off and
have your vehicle serviced at
the nearest dealer.
When the cooling fan for the
radiator is not turning, turn off
the engine immediately.
{Warning
Even when the engine has been
stopped, the engine coolant in the
radiator remains under pressure.
Immediately removing the radiator
cap could cause steam or hot
water to blow out, and you could
be scalded as a result. The
engine coolant in the reserve tank
may also be hot. Immediately
removing the cap could cause hot
water to blow out, and possibly
scald you. Perform inspection,
refilling, and replacement of
coolant only when its temperature
has cooled.
When removing the radiator cap
and reserve tank cap, use a thick
cloth to cover the cap and turn it
little by little.
You and others could be seriously
injured.