2018 CHEVROLET LOW CAB FORWARD check engine

Chevrolet Low Cab Forward Owner Manual (GMNA-Localizing-U.S.-
11254764) - 2018 - crc - 12/5/16
Vehicle Care 287
{Warning
If you find any abnormal
conditions with the wheel nuts
such as frequent loosening of
retightened nuts, have your
vehicle checked or serviced at the
nearest dealer as soon as
possible.
Fully engage the wheel wrench on a
wheel nut in order to tighten the nut
to the specified torque. However, do
not use a pipe as a handle
extension or your foot to apply force
on the wrench. This would tighten
the nut more than required and
might damage components.
Both under-tightening and
over-tightening of wheel nuts may
cause broken wheel studs or
cracked disc wheels and could lead
to wheel detachment. Adhere to the
specified tightening torques.
When replacing a tire with a new
one, use only a tire of the same
type and size as the replaced tire;
otherwise, driving safety could be affected. Avoid mixed use of
different types or different size tires
at all costs.
If a Tire Goes Flat
When the tire goes flat while driving,
ease off the accelerator pedal, avoid
hard braking, hold on to the steering
wheel firmly, and stop the vehicle.
The tire should be changed in a
safe, open location to prevent
obstructing other vehicles or
pedestrians.
{Warning
If you continue to drive on a flat
tire, undue force will be applied to
the wheel studs, possibly causing
the studs to break and the wheel
to come off. You and others could
be seriously injured.
See “Tire Replacement
Recommendations” underWheels
and Tires 0272.
Jump Starting
Jump Starting - North
America
When the Battery is
Discharged
Use a jumper cable (sold
separately) and the battery of
another vehicle to start the engine in
the following sequence.
{Danger
Follow the precautions listed in
the jump starting instructions
when working on or near the
battery. Personal injury
(particularly to eyes) or property
damage may result from battery
explosion, battery fluid or
electrical (short circuit) burns.
If battery fluid should come in
contact with an eye, immediately
wash away using a large amount
of water and continue washing for
(Continued)

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.

Chevrolet Low Cab Forward Owner Manual (GMNA-Localizing-U.S.-
11254764) - 2018 - crc - 12/5/16
306 Service and Maintenance
Maintenance Schedule Table
Letters Used to Indicate Maintenance Service Types
I :Inspect then clean, repair or replace as necessary
A : Adjust
R : Replace
T : Tighten to the specified torque
L : Lubricate
C : Clean
No. Service Interval
16 000 km/10,000 mi
24 000 km/15,000 mi
32 000 km/20,000 mi
48 000 km/30,000 mi
64 000 km/40,000 mi
72 000 km/45,000 mi
80 000 km/50,000 mi
96 000 km/60,000 mi
112 000 km/70,000 mi
120 000 km/75,000 mi
128 000 km/80,000 mi
144 000 km/90,000 mi
160 000 km/100,000 mi
168 000 km/105,000 mi
176 000 km/110,000 mi
Service intervals
months or
kilometers
(miles)
whichever
occurs first (1)
1 Engine noise check I - I I I - I I I - I I I - I
2 Valve lash - - - A - - - A - - - A - - - or every
12 months
3 Engine oil and oil filter (2) R - R R R - R R R - R R R - R or every
12 months
4 Fuel filter - R - R - R - R - R - R - R - or every
24 months

Chevrolet Low Cab Forward Owner Manual (GMNA-Localizing-U.S.-
11254764) - 2018 - crc - 12/5/16
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

Chevrolet Low Cab Forward Owner Manual (GMNA-Localizing-U.S.-
11254764) - 2018 - crc - 12/5/16
Service and Maintenance 313
rocker shaft bracket nuts before
checking and adjusting valve
clearance.
Check and adjust valve clearance
every 80 000 km (50,000 miles) or
12 months whichever occurs first.
3. Engine Oil and Oil Filter :
Change at interval noted below
depending upon driving conditions.
•Normal Service —Change every
16 000 km (10,000 miles) or
12 months whichever occurs first.
• Severe Service —Change every
8 000 km (5,000 miles) or 3 months
if you often drive under one or more
of these conditions: (a) driving in
dusty areas, (b) frequent idling or
idling for long periods, (c) driving
6 km (4 miles) or less in freezing
weather, or other short trips in cold
weather, where the engine does not
thoroughly warm up.
Change oil and filter as soon as you
can after driving in a dust storm.
When recommended oil is used, it
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 Driver Information Center (DIC)
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 0284.
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.

Chevrolet Low Cab Forward Owner Manual (GMNA-Localizing-U.S.-
11254764) - 2018 - crc - 12/5/16
314 Service and Maintenance
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 0231. 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. 14. DPF (Clean Filter) :
Clean the
filter every 160 000 km
(100,000 miles) or 3,000 hours
whichever occurs first.
15. DPF (Pressure Difference
Sensor 0 Point Adjustment) :
Adjust the sensor every 160 000 km
(100,000 miles) or 3,000 hours
whichever occurs first.
16. DPF (Pressure Difference
Sensor Hose) : Inspect the sensor
hose every 160 000 km
(100,000 miles) or 3,000 hours
whichever occurs first. Replace the
sensor hose every 400 000 km
(250,000 miles).
17. Fuel Line System : Inspect the
fuel tank, cap and lines for damage
which could cause leakage every
16 000 km (10,000 miles). Inspect
fuel cap for correct sealing ability
and indications of physical damage.
Replace any damaged or
malfunctioning parts.
18. Brake Lining and Pad for
Wear : Check drum brake lining and
disc brake pad for wear or cracks
every 16 000 km (10,000 miles).
Check brakes (including parking brake) more often if operating
conditions or driving habits result in
frequent braking.
Front disc brakes have built-in wear
noise indicators which are designed
to make a high pitched squeal or
cricket-like warning sound when the
brake pads are worn to the point
where new pads are needed.
When the truck is in motion, the
sound may be constant or it may
come and go. Pressing the brake
pedal firmly may cause the sound
to stop.
Have the brake linings or the brake
pads replaced by your authorized
dealer as soon as possible after the
warning first becomes evident.
Failure to do so can result in
expensive damage to the brake
system or a serious accident.
19. Brake Drum and Rotor for
Wear and Damage :
Check brake
drums (rear and parking) and rotors
(front) for wear or damage every
32 000 km (20,000 miles) or
12 months whichever occurs first.

Chevrolet Low Cab Forward Owner Manual (GMNA-Localizing-U.S.-
11254764) - 2018 - crc - 12/5/16
Service and Maintenance 315
20. Brake Electric Vacuum Pump
(4500HD, 4500XD models) :
Inspect the brake electric vacuum
pump operation every 16 000 km
(10,000 miles) or 12 months,
whichever occurs first.
21. Brake Fluid :Check the fluid in
the brake fluid reservoir every
16 000 km (10,000 miles). Replace
the fluid every 48 000 km
(30,000 miles).
22. Hydraulic Brake Booster Fluid
(5500HD, 5500XD models) :
Replace Dexron VI ATF fluid every
24 months or 30,000 miles
(48,000 km), whichever occurs first.
23. Brake Line and Hoses : Check
lines and hoses for proper hook-up,
binding, leaks, cracks, chafing, etc.
every 32 000 km (20,000 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.
24. Parking Brake Cable : Check
the parking brake cable every
16 000 km (10,000 miles) or
12 months whichever occurs first. 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.

Chevrolet Low Cab Forward Owner Manual (GMNA-Localizing-U.S.-
11254764) - 2018 - crc - 12/5/16
Service and Maintenance 317
Owner Checks and
Services
Before Driving
Proper care and driving is important
not only for extended service life of
your vehicle, but also for improved
fuel and oil economy. Drive carefully
and defensively. Be sure you know
how to use your truck and its
equipment before operating it.
Starting and Operating
Proper care and operation will not
only extend the service life of your
vehicle but also improve fuel
economy.
Check Around the Vehicle Before
Starting the Engine
Before pulling away, perform a
thorough safety check, making sure
there are no children or obstructions
around the vehicle.
Take off the chocks after confirming
that the parking brake is securely
applied. Sit behind the wheel, adjust
the seat position, and buckle up the
seat belt. The passengers are alsorequired to buckle up the seat belts.
Adjust the positions of the steering
wheel and mirrors. Lock the doors.
Turn the power of the dome light or
accessories OFF before starting the
engine.
Engine Conditions
Checking the Engine for
Startability and Abnormal Noises
1. Make sure the parking brake is securely engaged. Step firmly
on the brake pedal.
2. Make sure the selector lever is in "P" or "N" position.
For safety, firmly press the
brake pedal before starting the
engine.
3. Turn the engine control switch to start the engine.
Check that the engine starts
quickly with no abnormal
noises. Checking Condition of the Engine
at Low Speeds and during
Acceleration
1. Make sure the transmission is in the "P" or "N" position and
the parking brake is securely
engaged.
2. Turn the engine control switch to start the engine, and run it to
warm up.
3. Check that the engine is running at a speed within the
standard idle speed range.
During regeneration of the
diesel particulate filter (DPF),
the engine idle speed may
increase.
4. Drive the vehicle, making sure the accelerator pedal does not
stick when gradually
accelerating, the engine speed
rises smoothly and it does not
knock.