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Chevrolet Low Cab Forward Owner Manual (GMNA-Localizing-U.S.-
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228 Vehicle Care
This Engine Oil Viscosity Grade
Chart shows general information.
For this vehicle, oil with *W-40
viscosity is recommended.
Changing the Engine Oil and
Oil Filter
Engine oil and the oil filter are
important factors in engine
performance and lifespan. Be sure
to use only the specified oil and oilfilters. The engine oil level must be
checked and the oil should be
changed regularly according to the
Maintenance Schedule.
Use the indicated oil quantities only
as guidelines when changing the
engine oil. After changing the oil,
make sure the oil is at the required
level. See
Capacities and
Specifications 0335. Failure to use the recommended
engine oil could result in engine or
DPF breakdown, or in poor fuel
efficiency. Be sure to use the
recommended engine oil.
Engine oil change precaution:
.
When adding oil, remove the
dipstick.
. After adding oil, wait for at least
5 minutes before starting the
engine. Be sure to reinstall the
dipstick.
Discarded Parts, Oils and
Other Liquids
When changing oils, filters, engine
coolant or other liquids, be sure to
have a container ready in advance
for their disposal.
Use methods conforming to legal
requirements for discarding or
disposing of parts, oils, filters or
engine coolant after change or
replacement.
Do not dispose of used engine oil,
fuel or any other oil in a careless
manner such as pouring it on the
ground, into sewers, or into streams
Page 250 of 358
Chevrolet Low Cab Forward Owner Manual (GMNA-Localizing-U.S.-
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Vehicle Care 249
Rear Axle (Gear Oil Viscosity Chart)
Gear Oil Viscosity Chart
Select appropriate gear oil in accordance with the table below. It is important
to select the viscosity appropriate for the temperature at which your vehicle
operates. Use the following table for making correct selections.
Rear Axle (Oil Level
Check)
Rear Axle Differential Gear Oil
The rear axle differential gear oil
level must be checked for its level
and it must be changed according to
the Maintenance Schedule.
Use the oil quantities indicated later
in this section only as guidelines
when changing the rear axle
differential gear oil.
After changing the oil, ensure that it
is at the correct level.
Drained oil must be disposed of in a
method conforming to the regulatory
requirements in your state.
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Chevrolet Low Cab Forward Owner Manual (GMNA-Localizing-U.S.-
11254764) - 2018 - crc - 12/5/16
Service and Maintenance 305
Preventive Maintenance
As any mechanical device operates,
a certain amount of wear occurs.
The amount of wear depends on
certain variables–type and method
of operation and the schedule of
maintenance. These variables may
be emphasized as critical to
malfunction but each is dependent
upon the other. For example, if a
vehicle is repeatedly overloaded,
driven at excessive speed or
improperly shifted, no schedule of
maintenance can prevent
malfunction. Also, if a preventive
maintenance schedule is not
followed, or is improperly carried
out, no amount of correct vehicle
operation will prevent malfunction.
If vehicle application, operation and
preventive maintenance schedules
and procedures are followed and
properly carried out, the life of the
vehicle will be greatly extended. For example, regular attention to the
engine oil is essential. The oil level
must be periodically checked and oil
added whenever needed. Also, the
oil should be changed at the
intervals specified with the proper
quality and viscosity of oil. If your
engine should run excessively low
on oil or if the oil has lost its
lubricating qualities because of old
age, serious engine damage could
occur.
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Chevrolet Low Cab Forward Owner Manual (GMNA-Localizing-U.S.-
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312 Service and Maintenance
Remarks
(1)In case this column is blank,
follow kilometers (miles).
(2) Use of oils other than CK-4 may
require shorter maintenance
intervals and may cause
nonconformity to regulations. (CJ-4
can be used while it is available.)
Use of oils with other viscosity than
*W-40 may also require shorter
maintenance intervals and may
cause a problem with engine
durability.
(3) Refer to "Air Cleaner Indicator
Light" under Engine Air Cleaner/
Filter 0231.
(4) Initial check at 1 040 km
(650 miles) is required.
(5) Be sure to discard used grease
seal, and always use new grease
seal for installation.
Explanation of Complete
Vehicle Maintenance Schedule
The following is a brief explanation
of each of the services listed in the
preceding Complete Vehicle
Maintenance Schedule. 1. Engine Noise :
These
components have an effect on the
control of noise emissions.
Service Interval Maintenance procedureEngine
Every 16 000 km (10,000 miles) Inspect sound absorption materials for
tears, broken out sections or
attachment. Repair or replace as
necessary.
Cooling System
Every 16 000 km (10,000 miles) Inspect fan, shroud and radiator for
attachment, tears or cleanliness.
Replace as necessary.
Air intake system
Every 24 000 km (1,500 miles) Inspect all ducts, hoses and intake
silencers for leaks or chafing. Repair or
replace as necessary.
Exhaust system
Every 16 000 km (10,000 miles) Inspect silencer, pipes, gaskets, clamps
and mounting for exhaust gas leaks or
looseness. Repair or replace as
necessary.
Cab
Every 16 000 km (10,000 miles) Inspect sound absorption materials for
tears, broken out sections or
attachment. Repair or replace as
necessary.
2. Valve Lash : Incorrect valve
clearance will result in increased
engine noise and lower engine output, thereby adversely affecting
engine performance. Retorque
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Chevrolet Low Cab Forward Owner Manual (GMNA-Localizing-U.S.-
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Service and Maintenance 327
UsageFluid/Lubricant
Engine Oil Engine oils with the letters CK-4 are required for your vehicle. The CK-4
designation can appear either alone or in combination with other American
Petroleum Institute (API) designations, such as API CK-4/SL. These letters
show API levels of quality. To determine the preferred viscosity for your
vehicle's diesel engine, see Engine Oil0223.
Hydraulic Brake Booster (If
Equipped) DEXRON
®-VI Automatic Transmission Fluid.
Power Steerig Fluid DEXRON
®-VI Automatic Transmission Fluid.
Rear Axle Multi purpose gear oil SAE80W-90 GL-5, SAE90 GL-5
Rear Axle
(Limited slip differential (LSD)) Multi purpose gear oil SAE80W-90 GL-5, SAE90 GL-5 for limited slip
differential together with limited slip differential lubricant additive (GM
Part No. 88900330) or equivalent.
Windshield Washer Solvent Automotive windshield washer fluid that meets regional freeze protection requirements.
Page 341 of 358
Chevrolet Low Cab Forward Owner Manual (GMNA-Localizing-U.S.-
11254764) - 2018 - crc - 12/5/16
340 Technical Data
Oil filter—
Oil filter cartridge 63.7 Y(6.5 kgf m/47.0 lb ft)
Remarks:
*1see Engine Oil 0223.
Remarks:*2see Engine Coolant 0231.
Remarks:*3see Automatic Transmission Fluid 0229.
Remarks:*4see Rear Axle (Gear Oil Viscosity Chart) 0249 orRear Axle (Oil Level Check) 0249.
Remarks:*5only for vehicles equipped with optional limited slip differential.
Remarks:*6The fuel tank capacity is stated on a metal plate attached to the fuel tank body. Only fill the tank to
95 percent of its capacity; this allows room for the expansion of the fuel.
Remarks:
*7larger capacity batteries 31 (180-930) × 2 can also be used. However, do not mix batteries of different
types and from different makers.