2018 CHEVROLET LOW CAB FORWARD oil viscosity

Chevrolet Low Cab Forward Owner Manual (GMNA-Localizing-U.S.-
11254764) - 2018 - crc - 12/5/16
138 Driving and Operating
SymptomCauseCorrective Action Reference
Engine does not
start Starter does not
turn over, or weak Discharged batteries Recharge or replace See
Battery0247
Battery terminals
detached, loose,
or corroded After repairing corroded
section, connect the
terminals firmly
-
Starter ground wire
terminal detached,
loose, or corroded After repairing corroded
section, connect the
terminals firmly
-
Engine oil viscosity
too high Change to an oil with
proper viscositySee
Engine Oil
0 223
Starter or electrical
system is faulty
4-

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 145
SymptomCauseCorrective Action Reference
Loud or abnormal
noises From the
transmission
Insufficient
transmission oil
Add oilSee
Automatic
Transmission Fluid
0 229
Transmission inner
components faulty
4-
From differential Insufficient differential
gear oil
Add oilSee
Rear Axle
(Gear Oil Viscosity
Chart) 0249 or
Rear Axle (Oil
Level Check) 0249
Differential inner
components faulty
4-
From the
suspension Spring pins, shackles,
or stoppers worn
4-
From the driveshaft Poor lubrication in each
component
Lubricate themSee
Owner Checks
and Services 0317
Splines or bearings worn
4-

Chevrolet Low Cab Forward Owner Manual (GMNA-Localizing-U.S.-
11254764) - 2018 - crc - 12/5/16
152 Driving and Operating
Cold Weather Starting
If you plan ahead for cold weather,
starting and driving your vehicle
should be no problem. The following
tips will help ensure good starting in
cold weather.
Oil gets thicker as it gets colder,
which slows down the engine
cranking speed. The diesel engine
functions by the heat of
compression (and glow plugs when
cold), rather than through the use of
spark plugs as in a gasoline engine.
So, your engine must crank faster
than a gasoline engine before it will
start.
To be sure the engine can turn fast
enough to start, use SAE 10W-40
viscosity engine oil when prevailing
temperatures drop below 0 °C
(32 °F). See the oil quality and oil
viscosity recommendations. Using
the proper viscosity oil will make
starting easier down to -23 °C
(-10 °F). When prevailing
temperatures drop below -23 °C
(-10 °F), the engine block heater
may be needed for starting. See
Engine Heater0154. Maintenance Items to Aid Cold
Weather Starting
Since the basic principle of diesel
engine ignition is based on
compression, the diesel engine is
somewhat harder to start than a
gasoline engine when the
temperature is below freezing.
To help prevent hard starting
problems, special attention should
be given to following normal
maintenance items:
1. Neglecting to have the fuel filter and water separator
serviced can be one of the
major contributors to hard
starting. If water is permitted to
accumulate in the primary filter,
it will freeze and make starting
the engine impossible.
2. Make sure the fuel tank vent is open.
3. Always refuel at the end of a day's operation. Moisture will
condense in an empty tank;
therefore, the tank should be filled before leaving the vehicle
standing for an extended
period.
Do not use starting aids in the air
intake system. Such aids can cause
immediate engine damage. See
Fuel for Diesel Engines 0206.
Stopping the Engine
When stopping the engine, take the
following steps: 1. Bring the vehicle to a complete stop.
2. Firmly apply the parking brake.
3. Move the selector lever to the P position and make sure that
the shift indicator shows P.
4. Allow the engine to idle for approximately 3 minutes.
5. Turn the engine control switch to the ACC or LOCK position.
Do not shut down the engine
immediately after driving the vehicle.
Otherwise, a seizure or other
failures may result.

Chevrolet Low Cab Forward Owner Manual (GMNA-Localizing-U.S.-
11254764) - 2018 - crc - 12/5/16
154 Driving and Operating
Winter Cover
.Do not cover the front of the
radiator with newspapers,
cardboard or any other
flammable material to raise the
engine coolant temperature.
. 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 (Continued)
Warning (Continued)
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 0220.

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

Chevrolet Low Cab Forward Owner Manual (GMNA-Localizing-U.S.-
11254764) - 2018 - crc - 12/5/16
226 Vehicle Care
Consequently, the maintenance
interval of the DPF filter will be
reduced.
Oil Identification Logo
A logo (symbol) is used on most oil
containers to help you select the oil
you should use. The top portion of
the logo shows the oil quality by API
designations such as CK4 or others.
The center portion of the logo
shows the SAE viscosity grade,
such as SAE *W-40 (* indicates
viscosity on the low temperature
side). You should look for this logo
on the oil container, and use ONLY
oil containing the logo.Change Intervals
The oil and oil filter change intervals
for your engine are based on the
use of recommended oil quality and
viscosity, as well as high-quality
filters such as genuine GM oil filters.
Using oil other than recommended,
or oil and filter change intervals
longer than recommended, could
reduce engine life. Damage to
engines due to improper
maintenance or use of incorrect oil
quality and/or viscosity is not
covered by the new vehicle
warranty.
Your engine was filled with a
high-quality engine oil when it was
built. You do not have to change this
oil before the first recommended
change interval. Oil and filter
change intervals depend on how
you use your vehicle. For
information on the proper oil and
filter change intervals. See
Maintenance Schedule
0303. Engine Oil Additives
Engine oils contain a variety of
additives. Your engine should not
need any extra additives if you use
the recommended oil quality and
change intervals.
{Warning
Used engine oil contains harmful
contaminants that have caused
skin cancer in laboratory animals.
Avoid prolonged skin contact.
Clean skin and nails thoroughly
using soap and water–not mineral
oil, fuels or solvents. Launder or
discard clothing, shoes or rags
containing used engine oil.
Engine Oil and Gear Oil
Viscosity Charts
Select appropriate engine oil in
accordance with the table below.
It is also important to select the
viscosity appropriate for the
temperature at which your vehicle
operates. Use the following table for
making correct selections.

Chevrolet Low Cab Forward Owner Manual (GMNA-Localizing-U.S.-
11254764) - 2018 - crc - 12/5/16
Vehicle Care 227
Engine Oil
Engine oil viscosity (thickness) has
an effect on fuel economy and
cold-weather starting. Lower
viscosity engine oils can provide
better fuel economy; however,
higher temperature weather
conditions require higher viscosity
engine oils for satisfactory
lubrication.
When choosing an oil, consider the
range of temperature your vehicle
will be operated in before the next
oil change. Then, select the
recommended oil viscosity from the
chart.
Do not use any viscosity of oil not
recommended. Such oils could
cause engine damage.