2018 CHEVROLET LOW CAB FORWARD low oil pressure

Chevrolet Low Cab Forward Owner Manual (GMNA-Localizing-U.S.-
11254764) - 2018 - crc - 12/5/16
64 Instruments and Controls
Instruments and
Controls
Controls
Steering Wheel Adjustment . . . . 65
Horn . . . . . . . . . . . . . . . . . . . . . . . . . . . 65
Windshield Wiper/Washer . . . . . . 66
Power Outlets . . . . . . . . . . . . . . . . . 67
Cigarette Lighter . . . . . . . . . . . . . . . 67
Ashtrays . . . . . . . . . . . . . . . . . . . . . . . 68
Warning Lights, Gauges, and
Indicators
Warning Lights, Gauges, andIndicators . . . . . . . . . . . . . . . . . . . . 69
Instrument Cluster . . . . . . . . . . . . . 70
Speedometer . . . . . . . . . . . . . . . . . . 71
Odometer . . . . . . . . . . . . . . . . . . . . . . 71
Trip Odometer . . . . . . . . . . . . . . . . . 71
Tachometer . . . . . . . . . . . . . . . . . . . . 72
Fuel Gauge . . . . . . . . . . . . . . . . . . . . 72
Engine Coolant Temperature Gauge . . . . . . . . . . . . . . . . . . . . . . . . 72
Diesel Exhaust Fluid (DEF) Gauge . . . . . . . . . . . . . . . . . . . . . . . . 73
Seat Belt Reminders . . . . . . . . . . . 73
Battery Warning Light . . . . . . . . . . 73
Malfunction Indicator Lamp (Check Engine Light) . . . . . . . . . 74 Service Vehicle Soon Light . . . . 74
Brake System Warning Light
(Parking Brake Light) . . . . . . . . . 75
Antilock Brake System (ABS) Warning Light . . . . . . . . . . . . . . . . 77
Exhaust Brake Light . . . . . . . . . . . 78
Service Transmission Warning Light . . . . . . . . . . . . . . . . . . . . . . . . . 78
Automatic Transmission Fluid Temperature Warning Light . . . 78
Overdrive Off Light . . . . . . . . . . . . . 79
Wait-to-Start Light . . . . . . . . . . . . . 79
Engine Oil Pressure Light . . . . . . 79
Engine Oil Level Indicator Light . . . . . . . . . . . . . . . . . . . . . . . . . 80
Diesel Exhaust Fluid (DEF) Warning Light . . . . . . . . . . . . . . . . 80
Engine Shutdown Warning Light . . . . . . . . . . . . . . . . . . . . . . . . . 80
Idle Shutdown Light . . . . . . . . . . . . 81
Reduced Engine Power Light . . . . . . . . . . . . . . . . . . . . . . . . . 81
High-Beam On Light . . . . . . . . . . . 81
Daytime Running Lamps (DRL) Indicator Light . . . . . . . . . . . . . . . . 82
Cruise Control Light . . . . . . . . . . . 82
Information Displays
Driver Information Center (DIC) . . . . . . . . . . . . . . . . . 82
Vehicle Messages
Vehicle Messages . . . . . . . . . . . . . 86
Warning Buzzers . . . . . . . . . . . . . . 91

Chevrolet Low Cab Forward Owner Manual (GMNA-Localizing-U.S.-
11254764) - 2018 - crc - 12/5/16
Instruments and Controls 79
be accompanied by leakage of fluid
from the transmission
breather hose.
If the light stays on, or comes on
while driving, slow down and pull off
the road. Stop the vehicle at a safe
place and put the vehicle in
P (Park). With the engine idling, wait
until the light goes off. If the light
goes off, you can drive the vehicle
again. If the light does not go off,
have the automatic transmission
lubricating system checked by your
dealer.
Caution
Driving with the ATF warning light
constantly on can cause serious
mechanical damage to the
automatic transmission.
See Automatic Transmission 0185.
Overdrive Off Light
This light should come on briefly
when the engine control switch is
turned on as a check to make sure
the light is working. It should go out
automatically.
This light comes on when the
overdrive off switch on the selector
lever is turned on. Overdrive will not
operate even when the automatic
transmission is in D, unless engine
speed is excessive.
Wait-to-Start Light
This light comes on when the
engine control switch is turned to
the ON position and goes out when
preheating is complete.
See Starting and Stopping the
Vehicle 0149.
Engine Oil Pressure Light
This light should come on briefly
when the engine control switch is
turned to the ON position, and then
should go out after the engine is
started.
This light comes on when the
engine oil pressure has fallen below
the normal level while the engine is
running or the oil pressure across
the oil filter rises above the normal
level while the engine is running.
If the warning light comes on while
driving, immediately pull off to a
safe place and stop the engine.

Chevrolet Low Cab Forward Owner Manual (GMNA-Localizing-U.S.-
11254764) - 2018 - crc - 12/5/16
80 Instruments and Controls
Check the oil level in the engine
crankcase. If the oil level is normal,
restrictions are in the oil filter or
within the lubricating system. Have
the vehicle inspected at your dealer.
Do not run the engine with this light
on. It could damage the engine.
When this light comes on while
driving, a warning tone also sounds.
The oil level varies while the engine
is running right after it has stopped
or if the vehicle is on uneven
ground. As a result, the red engine
oil pressure warning light may
light up.
When checking the oil level, press
the engine oil level check switch on
level ground while the engine is
cool. The red engine oil pressure
warning light in combination with the
green engine oil level indicator light
can indicate if the engine oil level is
OK or low.
While driving, this light will also
activate the engine alarm and
automatic shutdown system.
SeeEngine Oil Level Indicator Light
0 80 and Engine Oil 0223.Engine Oil Level Indicator
Light
When the engine oil level check
switch is pushed with the engine
control switch in LOCK, the green
engine oil level indicator light will
come on if the engine oil level
is OK.
See Engine Oil Pressure Light 079
and Engine Oil 0223.
Diesel Exhaust Fluid
(DEF) Warning Light
This light should come on briefly
when the engine control switch is
turned to the ON position, and go off
when the engine has started.
This light comes on as a warning
related to the selective catalytic
reduction (SCR) system. If this light
comes on, check the DEF gauge.
Add DEF if necessary. If DEF level
is OK, have your vehicle serviced
by your dealer.
Also see Diesel Exhaust Fluid
0 170.
Engine Shutdown
Warning Light
The Engine Shutdown Warning light
comes on briefly when the engine
control switch is turned to the ON
position, as a check to show the
light is working. The light turns off
when the engine is started.

Chevrolet Low Cab Forward Owner Manual (GMNA-Localizing-U.S.-
11254764) - 2018 - crc - 12/5/16
130 Driving and Operating
1. Hold the regular brake pedaldown with your right foot and
apply the parking brake all the
way before shifting the
transmission. Follow the
Parking Brake instructions in
this manual for your vehicle.
2. To move the selector lever to "P" (Park), hold in the button
on the lever and push the lever
all the way toward the front of
your vehicle.
3. Turn the key to "LOCK".
4. Remove the key and take it with you.
5. Before you leave the driver's seat, be sure the vehicle is not
moving, or check that your
vehicle is in Park by trying to
pull the selector lever out of "P"
(Park) by pulling the selector
lever toward you without
pushing the button. If you can
do this, it means that the
selector lever was not fully
locked into "P" (Park).Driving Down a Long Slope
When driving down a long slope,
use the exhaust brake together with
the foot brakes. Using the exhaust
brake and low-gears reduces the
work load on the foot brakes and
yields greater braking force. Even
so, use the foot brakes
appropriately to prevent the engine
over-revving.
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 0201 and
Selector Lever 0194.
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 (Continued)

Chevrolet Low Cab Forward Owner Manual (GMNA-Localizing-U.S.-
11254764) - 2018 - crc - 12/5/16
142 Driving and Operating
SymptomCauseCorrective Action Reference
Oil pressure is low Improper engine oil
viscosity
Change to an oil with
proper viscositySee
Engine Oil
0 223
Engine oil level too low Add engine oil See
Engine Oil
0 223
Engine inner
components are faulty
4-
Meter, indicator/warning
lights or switches faulty
4-
Not enough engine power Parking brake not fully
released
Make sure it is fully
released
-
Brake dragging
4-
Air cleaner clogged
4-
Fuel filter clogged
4-
Engine control system
faulty
4-
Common rail system
faulty
4-
Engine faulty
4-
DPF clogged
4-

Chevrolet Low Cab Forward Owner Manual (GMNA-Localizing-U.S.-
11254764) - 2018 - crc - 12/5/16
Driving and Operating 155
Engine Alarm and
Automatic Shutdown
If the system senses any of the
following conditions: high engine
temperature, low engine oil pressure
or low engine coolant, the
corresponding warning light and
engine alarm (shutdown) warning
light will come on. If the engine
alarm (shutdown) warning light
comes on, you will also hear a tone
alarm.
If your vehicle has the engine
shutdown feature, your engine will
shut down in 30 seconds.Pull safely off the road and shut off
the engine. Do not start it until the
cause of the problem is known, and
the problem is fixed. However, if the
engine shuts down when you are
still in traffic, you can restart the
engine and get another 30 seconds
of operation. Do this only if you
have to, since there is a problem
that can harm the engine if it is not
fixed. See
Engine Shutdown
Warning Light 080.
Idle Shutdown
Idle Stop is a dealer programmable
function which will automatically turn
off the engine, at idle, when specific
programmed conditions are met.
See your dealer for details. When
the Idle Stop light comes on, it alerts
you that programmed conditions
have been met and the engine is
about to shut down. This light stays
on after the engine has stopped.
This indicator light will come on
when the engine control switch is
turned to the ON position and then
should go out after approximately
3 seconds. If the idling stop function does not
initiate, a transmission related
problem may have occurred. Please
contact your dealer. (There is a
Diagnostic Trouble Code (DTC) that
inhibits the idling stop function when
the Service Transmission Warning
Light is not illuminated).
High Idle System
Use high idle mode to increase
engine idle speed to 1,200 r/min
when the vehicle is stationary.

Chevrolet Low Cab Forward Owner Manual (GMNA-Localizing-U.S.-
11254764) - 2018 - crc - 12/5/16
156 Driving and Operating
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.-
11254764) - 2018 - crc - 12/5/16
Vehicle Care 217
Vehicle Care
General Information
General Information . . . . . . . . . . 218
California Proposition65 Warning . . . . . . . . . . . . . . . . . 218
California Perchlorate Materials Requirements . . . . . 218
Accessories and Modifications . . . . . . . . . . . . . . . . 218
Vehicle Checks
Doing Your OwnService Work . . . . . . . . . . . . . . . 218
Cab Tilting . . . . . . . . . . . . . . . . . . . . 220
Engine Compartment Overview . . . . . . . . . . . . . . . . . . . . 222
Engine Cover . . . . . . . . . . . . . . . . . 222
Engine Oil . . . . . . . . . . . . . . . . . . . . 223
Automatic Transmission Fluid . . . . . . . . . . . . . . . . . . . . . . . . 229
Engine Air Cleaner/Filter . . . . . . 231
Engine Coolant . . . . . . . . . . . . . . . 231
Engine Overheating . . . . . . . . . . 237
Power Steering Fluid . . . . . . . . . 240
Washer Fluid . . . . . . . . . . . . . . . . . 241
Brakes . . . . . . . . . . . . . . . . . . . . . . . 242
Brake Fluid . . . . . . . . . . . . . . . . . . . 246
Battery . . . . . . . . . . . . . . . . . . . . . . . . 247
Fuel Filter . . . . . . . . . . . . . . . . . . . . 248 Rear Axle (Gear Oil Viscosity
Chart) . . . . . . . . . . . . . . . . . . . . . . . 249
Rear Axle (Oil Level Check) . . . . . . . . . . . . . . . . . . . . . . 249
Noise Control System . . . . . . . . 250
Automatic Transmission Shift
Lock Control Function
Check . . . . . . . . . . . . . . . . . . . . . . . 251
Wiper Blade Replacement . . . . 252
Headlamp Aiming
Headlamp Aiming . . . . . . . . . . . . 254
Bulb Replacement
Bulb Replacement . . . . . . . . . . . . 254
Headlamps and Front Turn Signal . . . . . . . . . . . . . . . . . . . . . . . 257
Roofmarker Lamps . . . . . . . . . . . 261
Sidemarker Lamps (Including Turn Signal and Cornering
Lamps) . . . . . . . . . . . . . . . . . . . . . . 261
Taillamps, Turn Signal, Stoplamps, and Back-Up
Lamps . . . . . . . . . . . . . . . . . . . . . . 263
License Plate Lamp . . . . . . . . . . 263
Interior Lamps . . . . . . . . . . . . . . . . 264
Electrical System
Electrical System Overload . . . 264
Wheels and Tires
Wheels and Tires . . . . . . . . . . . . . 272 Tire Pressure . . . . . . . . . . . . . . . . . 284
Tire Rotation . . . . . . . . . . . . . . . . . 284
If a Tire Goes Flat . . . . . . . . . . . . 287
Jump Starting
Jump Starting - North
America . . . . . . . . . . . . . . . . . . . . . 287
Towing the Vehicle
Towing the Vehicle . . . . . . . . . . . 291
Appearance Care
Exterior Care . . . . . . . . . . . . . . . . . 293
Interior Care . . . . . . . . . . . . . . . . . . 299