2020 CHEVROLET LOW CAB FORWARD light

Chevrolet Low Cab Forward 5.2L Diesel Engine 4500 HD/XD/5500 HD/XD
Owner Manual (GMNA-Localizing-U.S.-13337621) - 2020 - crc - 12/5/18
Service and Maintenance 325
maintenance intervals and may
cause a problem with engine
durability.
(3)Refer to "Air Cleaner Indicator
Light" under Engine Air Cleaner/
Filter 0243.
(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 procedure
Engine
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 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.

Chevrolet Low Cab Forward 5.2L Diesel Engine 4500 HD/XD/5500 HD/XD
Owner Manual (GMNA-Localizing-U.S.-13337621) - 2020 - crc - 12/5/18
326 Service and Maintenance
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 0297.
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

Chevrolet Low Cab Forward 5.2L Diesel Engine 4500 HD/XD/5500 HD/XD
Owner Manual (GMNA-Localizing-U.S.-13337621) - 2020 - crc - 12/5/18
Service and Maintenance 329
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
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
10 400 km (6,500 miles). Note that
there are left and right hand
threads. Wheel nut tightening torque
500Y(362 lb·ft)
35. King Pin : Lubricate the grease
fitting on the king pins every
12 months or 16 000 km
(10,000 miles) whichever occurs
first.
36. Wheel Hub Bearing Grease :
Clean and repack front wheel
bearings every 24 months or
48 000 km (30,000 miles) whichever
occurs first.
37. Air Conditioner Blower
Filter : The air conditioner blower
filter should be removed and
cleaned once a month.
38. Exhaust Injector : Clean the
exhaust injector every 176,000 km
(110,000 miles).
39. DEF Supply Pump Filter
Element : Replace the DEF supply
pump filter element every
192 000 km (120,000 miles) or
24 months whichever occurs first. 40. Starter :
The color displayed by
the starter indicator light will change
from green to amber when the
number of times remaining is 0 or
below and the screen is selected.
When the indicator light (amber)
comes on, have the vehicle
inspected/serviced at the nearest
dealer.
41. Wiper Blades : Inspect wiper
blades for wear, cracking,
or contamination. Clean the
windshield and wiper blades,
if contaminated, replace wiper
blades that are worn or damaged,
or at least once a year. See Wiper
Blade Replacement 0265.

Chevrolet Low Cab Forward 5.2L Diesel Engine 4500 HD/XD/5500 HD/XD
Owner Manual (GMNA-Localizing-U.S.-13337621) - 2020 - crc - 12/5/18
330 Service and Maintenance
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 theseat belt. The passengers are also
required 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.

Chevrolet Low Cab Forward 5.2L Diesel Engine 4500 HD/XD/5500 HD/XD
Owner Manual (GMNA-Localizing-U.S.-13337621) - 2020 - crc - 12/5/18
Service and Maintenance 331
Recommended Daily
(Pre-operation) Inspections
These checks are in addition to, not
instead of, any legally required daily
inspections. See related topics
under "Maintenance Schedule",
especially if problems are found.
For safe and comfortable driving,
keep record of the distances driven
and the condition of the vehicle
during operation. Perform
inspections at appropriate intervals,
and perform maintenance in
accordance with the findings of the
inspections. If an inspection reveals
an abnormality or there was an
abnormality the previous time the
vehicle was driven, have the vehicle
repaired by the nearest dealer
before it is driven again.1. Components that showed abnormalities during the
previous operation
.Check components that
showed abnormalities
during the previous
operation 2. Checks performed at the
engine
.Fan belt looseness and
damage
. Engine oil level
. Engine coolant level
. Power steering fluid level
3. Checks performed from the driver's seat
.Brake fluid level
. Brake pedal free play
. Operation of meters,
gauges and warning/
indicator lights
. Engine startability,
abnormal noise and color of
exhaust gases
. Parking brake lever stroke
. Windshield washer fluid
spray condition and
windshield wiper
effectiveness
. Windshield washer fluid
level .
Steering wheel position and
free play
. Operation of horn and turn
signal lights
. Door lock operation
4. Checks performed during a walk around the vehicle
.Illumination, flashing,
contamination, damage and
obstruction of lights
. Contamination, damage ad
obstruction of windows,
mirrors and reflectors
. Leaf spring damage
. Oil, engine coolant, fuel,
brake fluid and power
steering fluid leaks
. Water separator
5. Checking wheels and tires .Air pressure
. Cracks and other damage
. Abnormal wear
. Tread depth

Chevrolet Low Cab Forward 5.2L Diesel Engine 4500 HD/XD/5500 HD/XD
Owner Manual (GMNA-Localizing-U.S.-13337621) - 2020 - crc - 12/5/18
332 Service and Maintenance
.Mounting condition of all
wheel nuts
6. Checks performed after the engine startup
.Oil, engine coolant, fuel,
brake fluid and power
steering fluid leaks
. Inspect the exhaust system,
checking that the tailpipe is
clear
7. Checks performed while driving the vehicle
.Brake effectiveness
. Engine abnormal noises
Keep the Floor Around the Driver
Seat Clean and Tidy
{Warning
It is extremely dangerous to have
empty cans, empty bottles,
or other items rolling around on
the floor because they could get
trapped under the brake pedal
and prevent brake application. (Continued)
Warning (Continued)
For proper pedal operation, it is
also essential to lay floor mats
properly. Incorrectly installed floor
mats would hinder free movement
of the pedals.
Do not use the dashboard pocket
or the top of the dashboard as a
place to put items that could roll,
which could interfere with your
driving. You and others could be
seriously injured.
Choose Your Footwear Suitable
for Driving
{Warning
Choose footwear that ensures
proper operation of pedals when
driving the vehicle. Use of
footwear unsuitable for driving
may cause an accident. The
driver could be seriously injured
when not wearing the proper
footwear.
Electrical System
Following the after-delivery service,
it is the owner's responsibility to
check all wiring periodically for
cracked, chafed or oil-soaked
insulation and maintain it in a clean
and tight condition to ensure
satisfactory operation of the
electrical system.
Headlights and Turn Signal
Lights
Turn the engine control switch to the
"ON" position, and then check the
way in which the headlights, turn
signal lights, and other exterior
lights come on and flash. In
addition, press the brake pedal to
confirm whether the stop lights
come on, and shift the transmission
to "R" position to confirm whether
the back up lights come on. Also
examine the lights for discoloration,
damage, and looseness.

Chevrolet Low Cab Forward 5.2L Diesel Engine 4500 HD/XD/5500 HD/XD
Owner Manual (GMNA-Localizing-U.S.-13337621) - 2020 - crc - 12/5/18
336 Service and Maintenance
Additional
Maintenance and Care
Owner Safety and Routine
Maintenance
Listed below are vehicle checks
which should be made periodically
by either the owner or a qualified
technician to ensure proper
performance and safety of your
vehicle. Take any problems promptly
to a technician for service advice.
For your safety and that of others,
any of the safety-related
components that may have been
damaged in a crash should be
checked and necessary repairs
performed before operating your
vehicle.
At the minimum, these routine
checks should be made every
6 months or 16,000 km
(10,000 miles), whichever comes
first. Whenever repairs are
necessary, have them completed
before operating the vehicle.A: Parking Brake :
Park on a fairly
steep hill and hold the vehicle with
the parking brake only. This checks
holding ability.
Before checking item (B) below, be
sure to have enough room around
the vehicle. Then firmly apply both
the parking brake see Parking
Brake 0211 and the regular brakes.
Do not use the accelerator pedal.
If the engine starts, be ready to turn
off the engine control switch at
once. Take these precautions
because the vehicle could move
without warning and possibly cause
injury or property damage.
B: Starter Safety Switch : Check
by trying to start the engine in each
gear. The starter should crank only
at selector position "P" or "N".
C: Transmission Shift Indicator :
Check that the indicator points to
the gear chosen.
D: Steering : Be alert for any
changes in steering action. An
inspection or service is needed
when: the steering wheel is harder to turn or has too much free play,
or when there are strange sounds
when turning or parking.
E: Wheel Alignment, Balance, and
Tires :
Check tires for abnormal
wear or damage. Also, check for
damaged wheels. A pull right or left
on a straight and level road may
show the need for a wheel
alignment. A vibration of the
steering wheel or seat at normal
highway speeds may mean a wheel
balancing is needed. Check tire
pressure when the tires are "cold,"
at least monthly, and whenever the
vehicle is serviced.
Check the pressure more often if
daily checks show it's needed.
(Refer to "Recommended Daily
(Pre-operation) Inspections" under
Owner Checks and Services 0330).
Change tire pressure as needed
when changing loads.
F: Brakes : Be alert to illumination
of the brake system warning light or
brake low vacuum warning light
(4500HD, 4500XD models) or the
tone alarm, or changes in braking
action, such as repeated pulling to

Chevrolet Low Cab Forward 5.2L Diesel Engine 4500 HD/XD/5500 HD/XD
Owner Manual (GMNA-Localizing-U.S.-13337621) - 2020 - crc - 12/5/18
Service and Maintenance 337
one side, unusual sounds when
braking, increased brake pedal
travel or harder pedal. The front and
rear brakes are attached to an auto
adjuster mechanism. If there are no
defects, as the pedal travel is
properly maintained, adjustments
are not necessary. Check regularly
that the brake fluid reservoir
(left-hand side of the instrument
panel) or HBB reservoir (5500HD,
5500XD models: left side behind the
cab) is properly filled and check for
fluid leaks. Any of these conditions
could indicate the need for brake
system inspection and/or service.
G: Exhaust System :Be alert for
any changes in the sound of the
exhaust system or any smell of
fumes. These are signs the system
may be leaking. Have it checked
and/or repaired at once. (Refer to
"Engine Exhaust Emissions Caution
(Carbon Monoxide)" under Engine
Exhaust 0168).
H: Windshield Wipers and
Washers : Check operation and
condition of the wiper blades. Check
the flow of the washer spray. I: Defroster :
Turn the outlet
selector knob to "Defroster" and the
fan speed control knob to the fully
clockwise position. Then check the
airflow from the ducts at the inside
base of the windshield.
J: Rearview Mirrors and Sun
Visors : Check that friction joints
hold mirrors and sun visors in place.
K: Horn : Sound the horn, now and
then, to be sure it works.
L: Lap-Shoulder Belts : Check the
seat belt system (including webbing,
buckles, latch plates and anchors)
for proper operation, and for
damage.
M: Seat Adjusters : When
adjusting the driver's manual seat,
be sure the seat adjusters latch by
pushing the seat forward and
backward. Do not attempt to adjust
the seat when the vehicle is in
motion.
N: Lamps : Check panel lighting,
warning lamps, indicator lamps and
interior lamps. On the outside,
check: license plate lamps, side
marker lamps, reflectors on outside mirrors, headlamps, parking lamps,
identification and clearance lamps,
taillights, brake lamps, turn signals,
cornering lamps, backup lamps and
hazard warning flashers. Have
headlamp aim checked immediately
if beams seem improperly aimed.
O: Glass, Mirrors, Lights and/or
Reflectors Condition :
Look for
broken, scratched, dirty or damaged
glass, mirrors, lamps or reflectors
that could reduce the view or
visibility, or cause injury. Replace,
clean or repair promptly.
P: Door Latches : Check that doors
close, latch and lock tightly. Check
for broken, damaged or missing
parts that might prevent tight
latching.
Q :Tilt Cab (Driving Position) : Be
sure the tilt lever is down and
locked.
R: Fluid Leaks : Check for fuel,
water, oil or other fluid leaks by
looking at the surface beneath the
vehicle after it has been parked for