Chevrolet Low Cab Forward Owner Manual (GMNA-Localizing-U.S.-
10716700) - 2017 - crc - 12/6/16
284 Vehicle Care
Checking the Oil Level
1. Remove the oil level plug.
2. Check that the oil level (1) isup to the lower edge of the oil
level plug hole (2). If the oil
level is tool low, add oil through
the oil level plug hole.
3. Fasten the oil level plug to the specified torque. Plug
tightening torque is 84 Nm
(8.6 kgFm/62 lb ft).
Any dirt on the plug should be
wiped off before installing it.
Noise Control System
The following information relates to
compliance with federal noise
emission standards for vehicles with
a Gross Vehicle Weight Rating
(GVWR) of more than 4 536 kg
(10,000 lb). The maintenance
schedule provides information on
maintaining the noise control system
to minimize degradation of the noise
emission control system during the
life of your vehicle. The noise
control system warranty is set forth
in your Warranty and Owner
Information book.
These standards apply only to
vehicles sold in the United States.
Tampering with Noise Control
System Prohibited
Federal law prohibits the following
acts or the causing thereof: 1. The removal or rendering inoperative by any person,
other than for purposes of
maintenance, repair or
replacement, of any device or
element of design incorporated
into any new vehicle for the
purpose of noise control, prior
to its sale or delivery to the
ultimate purchaser or while it is
in use; or
2. The use of the vehicle after such device or element of
design has been removed or
rendered inoperative by any
person.
Among those acts presumed to
constitute tampering are the acts
listed below.
Insulation:
Removal of the noise shields or any
undercab insulation.
Chevrolet Low Cab Forward Owner Manual (GMNA-Localizing-U.S.-
10716700) - 2017 - crc - 12/6/16
300 Vehicle Care
{Warning
Always use fuses specified for the
vehicle. Using fuses with a rating
other than that specified, or using
wire or tin foil, etc., could result in
fire or damage.
If the new fuses blow right away
and the cause is unknown,
contact your dealer.
Do not inspect or replace fuses
when the starter switch is in the
ON position. Doing so may lead
to an accident.
When inspecting fuses, be sure to
park the vehicle on flat, level
ground and apply chocks to the
wheels.Replacing Relays
Before replacing the relays, contact
the nearest dealer.
The vehicle may not be equipped
with all of the fuses, relays, and
features shown.
It is not necessary to open or close
the cover unless trouble is found.
The relay box structure makes it
difficult for water to enter. If you
should spill water or a beverage of
the cover, however, wipe it off
before opening the cover.
The area around the cover will get
warm when the vehicle is being
driven, but this is not abnormal.
Chevrolet Low Cab Forward Owner Manual (GMNA-Localizing-U.S.-
10716700) - 2017 - crc - 12/6/16
308 Vehicle Care
{Warning
Always use fuses specified by the
dealer when replacing the
slow-blow fuse. Using fuses with
a rating other than that specified,
or using wire or tin foil, etc., could
result in fire or damage.
If the new fuses blow right away
and the cause is unknown,
contact your dealer.
Do not inspect or replace fuses
when the starter switch is in the
ON position. Doing so may lead
to an accident.
When inspecting fuses, be sure to
park the vehicle on flat, level
ground and apply chocks to the
wheels.
It is not necessary to open or close
the cover unless trouble is found. The relay box structure makes it
difficult for water to enter. If you
should spill water or a beverage of
the cover, however, wipe it off
before opening the cover.
The area around the cover will get
warm when the vehicle is being
driven, but this is not abnormal.
Wheels and Tires
The operating load and cold inflation
pressure on the rim and wheel must
not exceed the rim and wheel
manufacturer's recommendations
even though the tire may be
approved for a higher load or
inflation. Rim and wheel may be
identified (stamped) with maximum
load and maximum cold inflation
rating. For rims and wheels not so
identified or for service conditions
exceeding the rate capacities,
consult the rim and wheel
manufacturer to determine rim and
wheel capacities for the intended
service. The factory-installed tires
on this vehicle were selected to
provide the best all-around tire
performance for normal operation.
When inflated, as shown on the
vehicle, they have the load carrying
capacity to operate satisfactorily at
all loads up to and including the full
rated load specified for the vehicle.
For more information concerning the
differences in capacities of tires and
rims, refer to the
“Tire and Rim
Association Inc. Yearbook,” or your
authorized dealer or tire dealer.
Chevrolet Low Cab Forward Owner Manual (GMNA-Localizing-U.S.-
10716700) - 2017 - crc - 12/6/16
Service and Maintenance 347
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.
Chevrolet Low Cab Forward Owner Manual (GMNA-Localizing-U.S.-
10716700) - 2017 - crc - 12/6/16
352 Service and Maintenance
7. SPARK PLUGS :Change every
160 000 km (100,000 miles).
8. SPARK PLUG WIRES : Clean
wires and inspect for burns, cracks
or other damage. Check the wire
boot fit at the coilpack and at the
spark plugs. And replace every
160 000 km (100,000 miles).
9. FUEL TANK, CAP AND LINES :
Inspect the fuel tank, cap and lines
for damage or leaks. Remove fuel
cap, inspect gasket for an even filler
neck imprint, and any damage.
Replace parts as needed.
10. ENGINE ACCESSORY DRIVE
BELT(S) : Inspect belts. Look for
cracks, fraying, wear, and proper
tension. Adjust or replace as
needed, and change every
160 000 km (100,000 miles).
11. EVAPORATIVE CONTROL
SYSTEM (ECS) : Visually check all
fuel and vapor lines and hoses for
proper hookup, routing, and
condition. Check that bowl vent and
purge valves work properly,
if equipped. Replace as needed. 12. SHIELDS AND UNDER HOOD
INSULATION :
Inspect shields and
under hood insulation for damage or
looseness. Adjust or replace as
required.
13. AIR INTAKE SYSTEM : Check
the air intake system installation to
see that gaskets are seated
properly and all hose connections,
fasteners, and other components
are tight. Also check to be sure that
the air cleaner housing is properly
seated, that the cover fits tightly,
and the wingnut(s) is/are tight.
Tighten connections and fasteners
or replace damaged parts as
required.
14. THERMOSTATICALLY
CONTROLLED ENGINE COOLING
FAN : With the engine off and below
normal operating temperature,
check to see that the fan can be
rotated by hand on fluid coupling or
viscous drives. Replace as
necessary. 15. AUTOMATIC TRANSMISSION
FLUID :
Check the automatic transmission
fluid level at each engine oil change
and replace fluid every 84 000 km
(52,500 miles). To check the fluid
level, first set the parking brake,
then start the engine in "P" position.
With the regular brakes applied,
move the selector lever through all
the gear positions, ending with "P".
You must check the fluid level with
the engine running at slow idle and
the truck must be on a level surface.
Chevrolet Low Cab Forward Owner Manual (GMNA-Localizing-U.S.-
10716700) - 2017 - crc - 12/6/16
354 Service and Maintenance
How to check: This operation could
be difficult and you may choose to
have this done at your dealer
Service Department.
1. Turn the engine control switch to
the "ON" position (not to start the
engine), and press the brake pedal
several times.
2. Check for the noisy sound of the
electric vacuum pump inside the
instrument panel at the same time
as vacuum warning buzzer sound,
and check that the brake low
vacuum warning light comes on.
3. Then, after you start the engine,
the main vacuum pump driven by
the engine will start running. If the
electric vacuum pump operation
(noisy sound) and the vacuum
warning buzzer stop, and the brake
low vacuum warning light goes off
thereafter, the operation is normal.
4. If you cannot hear the noisy
sound of the electric vacuum pump,
check the electrical wiring and
repair as necessary. If it cannot be
repaired, replace the electric
vacuum pump.20. BRAKE FLUID :
Check the fluid
in the brake fluid reservoir every
12 000 km (7,500 miles) and replace
fluid every 48 000 km
(30,000 miles).
21. BRAKE LINE AND HOSES :
Check lines and hoses for proper
hook-up, binding, leaks, cracks,
chafing, etc. every 48 000 km
(30,000 miles). Any questionable
parts should be replaced or repaired
at once. When rubbing or wear is
noted on lines or hoses, the cause
must be corrected at once.
22. HYDRAULIC UNIT : Change
every 10 years.
23. DIFFERENTIAL GEAR OIL :
Replace lubricant every 48 000 km
(30,000 miles) or every 24 months.
Check lubricant level every
12 000 km (7,500 miles) or every
12 months, and add lubricant to
within 0 to 10 mm (0 to 0.4 inch) of
the bottom edge of the filler hole if
necessary. 24. POWER STEERING FLUID :
Replace power steering fluid every
24 months or 60 000 km
(37,500 miles), whichever occurs
first.
25. STEERING WHEEL FREE
PLAY :
Check steering wheel free
play after the first 1 040 km
(650 miles) and then every
10 400 km (6,500 miles).
Steering wheel free play
10-50 mm (0.39-1.97 in)
26. STEERING GEAR BOX
TORQUE : Retighten the fixing bolts
of the steering gear box to the
specified torque every 48 000 km
(30,000 miles). Specified tightening
torque.
Steering gear box tightening torque
102 Y(75 lb·ft)
27. DRIVESHAFT FLANGE
TORQUE : Check the fixing bolts of
driveshaft flange for looseness or
damage first 12 000 km
(7,500 miles). Retighten the fixing
Chevrolet Low Cab Forward Owner Manual (GMNA-Localizing-U.S.-
10716700) - 2017 - crc - 12/6/16
364 Service and Maintenance
conforms to this maintenance
schedule. (Recommended oil: CK-4
(API designations))
4. Fuel Filter :Replace the fuel
filter every 24 000 km (15,000 miles)
or more frequently if clogged or
replace when the fuel filter indicator
light comes on (if equipped).
5. Pre-Fuel Filter/Water
separator : Replace the fuel filter
every 24 000 km (15,000 miles) or
more frequently if clogged or
replace when the fuel filter indicator
light comes on (if equipped).
6. Air Cleaner Filter : The level of
dirt in the air cleaner element can
be checked against the indicator.
Replace the air cleaner filter when
the multi-information display (MID)
shows "CHECK AIR FILTER".
7. Damage to Air Intake Ducts and
Hoses : Check for damage of air
intake ducts and hoses and that
those are correctly installed every
24 000 km (15,000 miles) or
12 months. Replace or adjust those
if necessary. 8. Drive Belts :
Check belt driving
the fan, alternator or A/C
compressor every 16 000 km
(10,000 miles). Look for cracks,
fraying, wear, and proper tension.
9. Engine Bolt Torques : Loosened
bolts result in lower engine output.
Check and adjust manifold
mounting, and injectors to correct
torque every 80 000 km
(50,000 miles).
10. Rotate Tires : To equalize wear,
rotate tires and adjust tire pressures
every 10 400 km (6,500 miles). See
Tire Rotation 0323.
11. Engine Cooling System : At
12 months or 16 000 km
(10,000 miles) intervals, wash
radiator cap and filler neck with
clean water, pressure test system
and radiator cap for proper pressure
holding capacity, tighten hose
clamps and inspect condition of all
cooling and heater hoses. Replace
hoses if cracked, swollen or
otherwise deteriorated. Have the
hoses replaced by your authorized
dealer. 12. Engine Coolant :
Inspect the
engine coolant every 12 months.
Replace the engine coolant every
24 months, drain the engine coolant
by opening the drain plug at the
bottom of the radiator core, flush
and refill the engine cooling system
with a new engine coolant. Refer to
"Preparing Engine Coolant" in
Engine Coolant 0263. Have the
Engine Coolant replaced by your
authorized dealer.
13. Exhaust System : Check the
complete exhaust system every
16 000 km (10,000 miles). Check
body areas near the exhaust
system. Look for broken, damaged,
missing, or out-of-position parts.
Also inspect for open seams, holes,
loose connections, or other
conditions which could cause heat
build-up at the rear body floor pan,
or could let exhaust fumes seep into
the passenger compartment. Dust
or water in the cabin may indicate a
leak in that area. Required repairs
should be made at once.
Chevrolet Low Cab Forward Owner Manual (GMNA-Localizing-U.S.-
10716700) - 2017 - crc - 12/6/16
366 Service and Maintenance
25. Automatic Transmission
Fluid :Check the automatic
transmission fluid level at each
engine oil change and replace fluid
every 48 000 km (30,000 miles). Do
not overfill.
26. Differential Gear Oil : Replace
lubricant every 48 000 km
(30,000 miles). Check lubricant level
every 16,000 km (10,000 miles) or
every 12 months, and add lubricant
to within 0 to 10 mm (0 to 0.4 inch)
of the bottom edge of the filler hole
if necessary.
27. Power Steering Fluid :
Replace power steering fluid every
24 months or 48 000 km
(30,000 miles), whichever occurs
first.
28. Power Steering Oil Hoses :
Replace power steering oil hoses
every 24 months or 80 000 km
(50,000 miles), whichever occurs
first.
29. Steering Wheel Free Play :
Check steering wheel free play after
the first 1 040 km (650 miles) and
then every 10 400 km (6,500 miles). Steering wheel free play
10-50 mm (0.39-1.97 in)
30. Steering Gear Box Torque :
Retighten the attaching bolts of the
steering gear box to the specified
torque every 12 months or every
32 000 km (20,000 miles) whichever
occurs first. Steering gear box tightening torque
103 Y(76 lb·ft)
31. Driveshaft Flange Torque :
Check the fixing bolts of driveshaft
flange for looseness or damage
after the first 16 000 km
(10,000 miles). Driveshaft flange tightening torque
103Y(76 lb·ft)
32. Driveshaft Lubrication :
Lubricate the grease fitting on the
center bearing, as well as each
universal joint and spline coupling
every 12 months or 16 000 km
(10,000 miles) whichever occurs
first. 33. Leaf Spring U-bolt Torque :
Tighten the U-Bolt nuts to the
specified torque after the first
1 040 km (650 miles), thereafter
every 16 000 km (10,000 miles).
Model Leaf spring U-bolt nut tightening torque
Front Rear
3500HD 127 Y
(94 lb·ft) 177
Y
(131 lb·ft)
4500HD 127 Y
(94 lb·ft) 177
Y
(131 lb·ft)
4500XD 196 Y
(145lb·ft) 177
Y
(131 lb·ft)
5500HD, 5500XD 196
Y
(145lb·ft) 284
Y
(209 lb·ft)
34. Wheel Nut Torque : Check tires
for excessive or abnormal wear,
or damage. Also check tire inflation
pressures and adjust.
Be sure wheels are not bent or
cracked and that wheel nuts have
been tightened to the specified
torque after the first 1,040 km
(650 miles) and then every