2020 CHEVROLET LOW CAB FORWARD air condition

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
Vehicle Care 291
Tire sizeTire air pressure
kPa (psi) GVW
kg (lb.)
Front RearFront Rear
LT215/85R16E LT215/85R16E 550 (80)550 (80) 6 577
(14,500)
225/70R19.5F 225/70R19.5F 590 (85)590 (85) 7 258
(16,000)
225/70R19.5F 225/70R19.5F 620 (90)620 (90) 8 142
(17,950)
225/70R19.5F 225/70R19.5F 660 (95)660 (95) 8 845
(19,500)
See “VIN, Weight Rating, and
Greenhouse Gas (GHG) Emissions
Plate” underVehicle Identification
Number (VIN) 0343.
See “Tire Load and Inflation Table”
under Tire Pressure 0297.
{Warning
Insufficiently inflated or worn-out
tires are highly dangerous as they
easily skid and can even burst.
(Continued)
Warning (Continued)
Should they burst, the tires may
burn and this could cause a fire in
the vehicle.
If you drive on under-inflated or
flat tires, the wheel studs will be
placed under excessive stress.
Under such conditions, the bolts
(Continued)
Warning (Continued)
may break and the wheel may
detach from the vehicle, possibly
causing a crash.
Over-inflated tires result in a
harsh ride and are likely to cause
damage to the cargo.
Under-inflated tires build up heat(Continued)

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
314 Vehicle Care
Warning (Continued)
use carbon tetrachloride,
gasoline, benzene or naphtha for
any cleaning purpose.
Open all vehicle doors for
ventilation when ANY cleaning
agents or other chemicals are
used in the interior. Overexposure
to some vapors may result in a
health problem that is more likely
to occur in small, unventilated
spaces.
You and others could be seriously
injured.
The interior of the vehicle must
never be cleaned using acidic or
alkaline solvents, or petroleum
ether, gasoline, and other organic
solvents. Failure to observe this
precaution can result in
discoloration and staining. It should
be noted that certain types of
cleaning products contain these
compounds. Be sure to read
cleaning product labels carefully. Air fresheners (liquid, solid, gel,
or plate types) must not come into
direct contact with, or spill onto,
interior components such as the air
conditioning or audio system.
Compounds contained in these
products can cause discoloration,
staining, or peeling of paint.
Glass cleaners that contain these
compounds must not be used to
clean the inside of the windshield or
window glass. To clean the glass,
wipe it using a cloth wet with warm
or cold water.
To avoid possible permanent
discoloration of light colored seats,
Do not let materials with non-fast
colors come into contact with seat
trim materials until these materials
are totally dry. This includes certain
types of casual clothing, such as
colored denims, corduroys, leathers,
and suedes, as well as decorative
paper.
With the use of modern trim
materials, it is very important that
you use proper cleaning techniques
and cleaners. Failing to do this on
the first cleaning may result in waterspots, spot rings, or setting of stains
or soilage
—all of which are more
difficult to remove in a second
cleaning.
Dust and loose dirt that collect on
interior fabric should be removed
often with a vacuum cleaner or soft
bristle brush. Wipe vinyl or leather
trim regularly with a clean, damp
cloth. Normal trim soils, spots,
or stains can be cleaned with these
cleaners.
Remember these basic steps before
cleaning:
. Remove stains as quickly as
possible before they set.
. Use a clean cloth or sponge,
and change to a clean area
often. A soft brush maybe used
if stains persist.
. Use solvent-type cleaners only
in a well ventilated area: also, do
not saturate the stained area.
. If a ring forms after spot
cleaning, clean the entire area
immediately.

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 317
Service and
Maintenance
Maintenance Schedule
Maintenance Schedule . . . . . . . 317
Owner Checks and Services
Owner Checks andServices . . . . . . . . . . . . . . . . . . . . 330
Additional Maintenance
and Care
Additional Maintenanceand Care . . . . . . . . . . . . . . . . . . . . 336
Recommended Fluids,
Lubricants, and Parts
Recommended Fluids andLubricants . . . . . . . . . . . . . . . . . . . 339
Maintenance Replacement Parts . . . . . . . . . . . . . . . . . . . . . . . . 341
Maintenance
Schedule
Caution
Damage caused by improper
maintenance can lead to costly
repairs and may not be covered
by the vehicle warranty.
Maintenance intervals, checks,
inspections, recommended fluids,
and lubricants are important to
keep the vehicle in good working
condition.
Do not have chemical flushes that
are not approved by GM
performed on the vehicle. The
use of flushes, solvents, cleaners,
or lubricants that are not
approved by GM could damage
the vehicle, requiring expensive
repairs that are not covered by
the vehicle warranty.
Make sure the vehicle is inspected
at regular intervals. Inspections and
maintenance enable you to use the vehicle with peace of mind. They
also extend the vehicle's
service life.
For safe and economical driving, we
recommend that you have your
vehicle inspected and serviced
regularly according to the schedule
indicated in this chapter.
To drive your vehicle safely and at
minimum cost, it is essential to have
your vehicle regularly inspected and
serviced at your dealer as per the
specified maintenance schedule.
Contact your dealer for inspection
that requires disassembly and/or
special equipment.
The Maintenance Schedule in this
manual and a Warranty Information
Booklet are supplied with your
vehicle. Read all publications for a
full understanding of your vehicle's
maintenance needs.
The quality of maintenance your
new vehicle receives is as important
as the regularity with which it is
serviced. Authorized dealers provide
nationwide quality in customer
service. The program includes the

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
324 Service and Maintenance
No. Service Interval16 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)
34 Wheel nut torque (4) Every 10 400 km (6,500 miles)
35 King pin L - L L L - L L L - L L L - L or every
12 months
36 Wheel hub bearing grease
- Front (5) - - - R - - - R - - - R - - - or every
24 months
37 Air conditioner blower
filter Cleaned once a month
38 Exhaust injector Cleaned every 176,000 km (110,000 miles)
39 DEF supply pump filter
element Every 192 000 km (120,000 miles): R or every
24 months
40 Starter When the starter indicator light (amber) comes on: R
41 Windshield wiper blades Replace every 12 months
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

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 327
Engine Coolant0243. 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 crash.
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.
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.

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
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