air condition CHEVROLET LOW CAB FORWARD 2020 Owner's Guide

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

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

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
Technical Data 355
Engine Drive Belt Routing
Fan Belt and Air Conditioning
Compressor Belt
See theMaintenance Schedule
0 317.
No. Name
1 Fan belt
2 Fan pulley
3 A/C belt
4 A/C compressor
5 Tension pulley
6 Crank pulley No.
Name
7 Alternator
If your air conditioning system is
functioning properly, it is not
necessary to remove and replace
the refrigerant or compressor oil.
. A V-ribbed belt is used for the
fan belt. This type of belt
requires the tension to be
adjusted more accurately than is
required with the conventional V
belt. Inappropriate tension could
cause the belt to make noise or
break. When the fan belt is
damaged, electricity is not
properly generated or becomes
a cause of engine overheating.
You must check the tension of
the fan belt carefully.
. Use dealer-certified genuine
parts when changing the
fan belt.
. Have the vehicle inspected and
serviced at your dealer. .
The air conditioning drive belt,
if equipped, must be adjusted
after fan belt adjustment. If the
belt is not adjusted properly, the
A/C belt may experience
excessive tension, and possible
premature failure.

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
362 Customer Information
Publication Ordering
Information
Service Manuals
Service manuals have the diagnosis
and repair information on the
engine, transmission, axle,
suspension, brakes, electrical
system, steering system, body, etc.
Customer Literature
Owner’s manuals are written
specifically for owners and are
intended to provide basic
operational information about the
vehicle. The owner ’s manual
includes the Maintenance Schedule
for all models.
Customer literature publications
available for purchase include
owner ’s manuals, warranty
manuals, infotainment manuals, and
portfolios. Portfolios include an
owner ’s manual, warranty manual,
infotainment manual, if applicable,
and zip lock bag or pouch.
Current and Past Models
Service manuals and customer
literature are available for many
current and past model year GM
vehicles.
To order, call 1-800-551-4123
Monday–Friday, 8:00 a.m.–6:00 p.m.
eastern time
For credit card orders only (VISA,
MasterCard, or Discover), see
Helm, Inc. at: www.helminc.com.
To order by mail, write to:
Helm, Incorporated
Attention: Customer Service
47911 Halyard Drive
Plymouth, MI 48170
Make checks payable in U.S. funds.
Radio Frequency
Statement
This vehicle has systems that
operate on a radio frequency that
complies with Part 15 of the Federal
Communications Commission (FCC)
rules. Operation is subject to the following
two conditions:
1. The device may not cause harmful interference.
2. The device must accept any interference received, including
interference that may cause
undesired operation of the
device.
Changes or modifications to any of
these systems by other than an
authorized service facility could void
authorization to use this equipment.

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
Customer Information 363
Reporting Safety
Defects
Reporting Safety Defects
to the United States
Government
If you believe that your vehicle
has a defect which could cause
a crash or could cause injury or
death, you should immediately
inform the National Highway
Traffic Safety Administration
(NHTSA) in addition to notifying
General Motors.
If NHTSA receives similar
complaints, it may open an
investigation, and if it finds that
a safety defect exists in a group
of vehicles, it may order a recall
and remedy campaign.
However, NHTSA cannot
become involved in individual
problems between you, your
dealer, or General Motors.To contact NHTSA, you may call
the Vehicle Safety Hotline
toll-free at 1-888-327-4236 (TTY:
1-800-424-9153); go to
http://
www.safercar.gov; or write to:
Administrator, NHTSA
1200 New Jersey Avenue, S.E.
Washington, D.C. 20590
You can also obtain other
information about motor vehicle
safety from http://
www.safercar.gov
.
Reporting Safety Defects
to General Motors
In addition to notifying NHTSA in a
situation like this, notify General
Motors.
Call 1-800-862-4389, or write:
Chevrolet Motor Division
Chevrolet Customer Assistance
Center
P.O. Box 33170
Detroit, MI 48232-5170
Vehicle Data
Recording and
Privacy
The vehicle has a number of
computers that record information
about the vehicle’s performance and
how it is driven or used. For
example, the vehicle uses computer
modules to monitor and control
engine and transmission
performance, to monitor the
conditions for airbag deployment
and deploy them in a crash, and,
if equipped, to provide antilock
braking to help the driver control the
vehicle. These modules may store
data to help the dealer technician
service the vehicle or to help GM
improve safety or features. Some
modules may also store data about
how the vehicle is operated, such as
rate of fuel consumption or average
speed. These modules may retain
personal preferences, such as radio
presets, seat positions, and
temperature settings.

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
Index 365
IndexA
Accessories andModifications . . . . . . . . . . . . . . . . . . 230
Add-On Electrical Equipment . . . 227
Additional Maintenance and Care . . . . . . . . . . . . . . . . . . . . . . 336
Adjustments Seat, Initial Drive . . . . . . . . . . . . . . . 26
Agreements Trademarks and License . . . . . .119
Air Cleaner/Filter, Engine . . . . . . . 243
Air Conditioning . . . . . . . . . . . . . . . . 121
Air Filter, Passenger Compartment . . . . . . . . . . . . . . . . . 125
Air Vents . . . . . . . . . . . . . . . . . . . . . . . 124
AM-FM Radio . . . . . . . . . . . . . . . . . . . . 85
Antenna Fixed Mast . . . . . . . . . . . . . . . . . . . . . 90
Antilock Brake System (ABS) . . . 207
Warning Light . . . . . . . . . . . . . . . . . . . 64
Appearance Care Exterior . . . . . . . . . . . . . . . . . . . . . . . 307
Interior . . . . . . . . . . . . . . . . . . . . . . . . 313
Assistance Program,
Roadside . . . . . . . . . . . . . . . . . . . . . . 358
Audio Bluetooth . . . . . . . . . . . . . . . . . . . . . 108 Audio Players
CD . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 90
Automatic Transmission . . . . . . . . . . . . . . . . . 196
Transmission Fluid . . . . . . . . . . . 241
Automatic Transmission Selector Lever . . . . . . . . . . . . . . . . 205
Shift Lock Control Function
Check . . . . . . . . . . . . . . . . . . . . . . . 264
Automatic Transmission Fluid Temperature Warning Light . . . . . 66
Automatic Transmission Overdrive Off . . . . . . . . . . . . . . . . . . 206
Auxiliary Devices . . . . . . . . . . . . . . . . . . . . . . . 107
Axle, Rear . . . . . . . . . . . . . . . . . 261, 262
B
Battery - North America . . . . 259, 301
Battery Warning Light . . . . . . . . . . . . 61
Biodiesel . . . . . . . . . . . . . . . . . . . . . . . 219
Blade Replacement, Wiper . . . . . 265
Bluetooth
Overview . . . . . . . . . . . . . . . . . . . . . . 111
Bluetooth Audio . . . . . . . . . . . . . . . . 108
Brake Exhaust . . . . . . . . . . . . . . . . . . . . . . 213
System Warning Light . . . . . . . . . . 62

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
366 Index
Brakes . . . . . . . . . . . . . . . . . . . . . . . . . . 253Antilock . . . . . . . . . . . . . . . . . . . . . . . 207
Exhaust Light . . . . . . . . . . . . . . . . . . . 65
Fluid . . . . . . . . . . . . . . . . . . . . . . . . . . 258
Parking . . . . . . . . . . . . . . . . . . . . . . . .211
Braking . . . . . . . . . . . . . . . . . . . . . . . . . 134
Break-In, New Vehicle . . . . . . . . . . 156
Bulb Replacement Headlamp Aiming . . . . . . . . . . . . . 267
Headlamps . . . . . . . . . . . . . . . . . . . 267
Headlamps and Front TurnSignal . . . . . . . . . . . . . . . . . . . . . . . 270
Interior Lamps . . . . . . . . . . . . . . . . 277
License Plate Lamps . . . . . . . . . 276
Roofmarker Lamps . . . . . . . . . . . 274
Sidemarker Lamps . . . . . . . . . . . 274
Taillamps, Turn Signal, Stoplamps, and Back-up
Lamps . . . . . . . . . . . . . . . . . . . . . . 276
Buzzers, Warning . . . . . . . . . . . . . . . . 79
C
Cab Tilting . . . . . . . . . . . . . . . . . . . . . . 233
California Perchlorate MaterialsRequirements . . . . . . . . . . . . . . . 230 California
Proposition
65 Warning . . . . . . . . . .230, 259, 301,
Back Cover
Capacities and Specifications . . . . . . . . . . . . . . . . . 349
Carbon Monoxide
Engine Exhaust . . . . . . . . . . . . . . . 168
Winter Driving . . . . . . . . . . . . . . . . 142
Cargo Lamp . . . . . . . . . . . . . . . . . . . . . 84
Caution, Danger, and Warning . . . . 3
CD Player . . . . . . . . . . . . . . . . . . . . . . . 90
Check Engine Light (MalfunctionIndicator) . . . . . . . . . . . . . . . . . . . . . . 61
Child Restraints
Systems . . . . . . . . . . . . . . . . . . . . . . . . 39
Cleaning Exterior Care . . . . . . . . . . . . . . . . . 307
Interior Care . . . . . . . . . . . . . . . . . . 313
Climate Control Systems . . . . . . . 121
Air Conditioning . . . . . . . . . . . . . . 121
Heating . . . . . . . . . . . . . . . . . . . . . . . 121
Cluster, Instrument . . . . . . . . . . . . . . 57
Cold Weather Operation . . . . . . . . 221
Collision Damage Repair . . . . . . . 359 Compartments
Storage . . . . . . . . . . . . . . . . . . . . . . . . . 42
Control of a Vehicle . . . . . . . . . . . . . 130
Coolant Engine . . . . . . . . . . . . . . . . . . . . . . . . 243
Engine Temperature Gauge . . . . 60
Cooling . . . . . . . . . . . . . . . . . . . . . . . . . 121
Cornering Lamps . . . . . . . . . . . . . . . . 83
Cover
Engine . . . . . . . . . . . . . . . . . . . . . . . . 235
Covers
Winter . . . . . . . . . . . . . . . . . . . . . . . . 163
Cruise Control . . . . . . . . . . . . . . . . . . 214 Light . . . . . . . . . . . . . . . . . . . . . . . . . . . . 70
Cupholders . . . . . . . . . . . . . . . . . . . . . . 44
Customer Assistance . . . . . . . . . . . 357 Offices . . . . . . . . . . . . . . . . . . . . . . . . 357
Text Telephone (TTY)Users . . . . . . . . . . . . . . . . . . . . . . . 357
Customer Information Publications Ordering
Information . . . . . . . . . . . . . . . . . . 362
Customer Satisfaction Procedure . . . . . . . . . . . . . . . . . . . . . 356
Cybersecurity . . . . . . . . . . . . . . . . . . . 364