2020 CHEVROLET LOW CAB FORWARD warning

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

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 341
Be sure to use the LSD gear oil
additive mentioned above in
vehicles equipped with limited slip
differentials, and ensure there is an
appropriate amount of the LSD gear
oil additive, otherwise a chattering
noise and/or excessive vibration
may occur when turning.
If abnormal noises occur despite
having used the specified LSD gear
oil additive, have it inspected and
serviced at your dealer.Maintenance
Replacement Parts
Replacement Parts
Please contact your dealer for
genuine GM parts.
{Warning
If part replacement is necessary,
the part must be replaced with
one of the same part number or
with an equivalent part. Use of a
replacement part of lesser quality
may result in personal injury or
damage to the vehicle.

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
342 Service and Maintenance
5.2L Diesel
PartGM Part Number
Engine Air Cleaner 97780479
Engine Oil Filter 98298404
Fuel Filter: Engine Side 98147525
Fuel Filter: Chassis Side 98037481
Replacement Fasteners
During vehicle maintenance, any
fasteners used to replace older
ones must have the same
measurements and strength as
those removed, whether metric or
customary. Fasteners taken from
the vehicle should be saved for
reuse in the same location when
possible. Where a fastener cannot
be used again, take care to choose
a replacement that matches the old
one. For information and help, see
your dealer.{Warning
This vehicle is primarily
dimensioned in the metric system.
Most fasteners are metric and
many are very close in dimension
to well-known customary
fasteners in the inch system.
Mismatched or incorrect fasteners
can result in damage to the
vehicle or possibly personal
injury.

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

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 367
D
Damage Repair, Collision . . . . . . . 359
Danger, Warning, and Caution . . . . 3
Daytime Running Lamps (DRL)Indicator Light . . . . . . . . . . . . . . . . . . 69
Devices Auxiliary . . . . . . . . . . . . . . . . . . . . . . 107
Diesel Engine Engine Alarm andAutomatic Shutdown . . . . . . . . 164
Diesel Exhaust Fluid . . . . . . . . . . . . 180
Diesel Exhaust Fluid (DEF) Gauge . . . . . . . . . . . . . . . . . . . . . . . . . 60
Diesel Exhaust Fluid (DEF)
Warning Light . . . . . . . . . . . . . . . . . . 68
Diesel Particulate Filter . . . . . . . . . 171
Distracted Driving . . . . . . . . . . . . . . . 130
Dome Lamps . . . . . . . . . . . . . . . . . . . . 84
Door Locks . . . . . . . . . . . . . . . . . . . . . . . . . . . 18
Power Locks . . . . . . . . . . . . . . . . . . . . 21
Drive Belt Routing, Engine . . . . . . 355
Driver Behavior . . . . . . . . . . . . . . . . . 129
Driver Information Center (DIC) . . . . . . . . . . . . . . . . . . . 70
Driving Better Fuel Economy . . . . . . . . . 129
Emergencies . . . . . . . . . . . . 145, 155 Driving (cont'd)
Hill and Mountain Roads . . . . . . 141
If the Vehicle is Stuck . . . . . . . . . 144
Wet Roads . . . . . . . . . . . . . . . . . . . 140
Winter . . . . . . . . . . . . . . . . . . . . . . . . 142
E
Electrical Equipment,
Add-On . . . . . . . . . . . . . . . . . . . . . . . 227
Electrical System
Overload . . . . . . . . . . . . . . . . . . . . . 277
Emergencies . . . . . . . . . . . . . . 145, 155
Engine Air Cleaner/Filter . . . . . . . . . . . . . 243
Alarm and Automatic
Shutdown . . . . . . . . . . . . . . . . . . . 164
Check Light (Malfunction Indicator) . . . . . . . . . . . . . . . . . . . . . . 61
Checks Before Operating . . . . . 166
Compartment Overview . . . . . . . 234
Coolant . . . . . . . . . . . . . . . . . . . . . . . 243
Coolant Temperature Gauge . . . . 60
Cover . . . . . . . . . . . . . . . . . . . . . . . . . 235
Drive Belt Routing . . . . . . . . . . . . 355
Exhaust . . . . . . . . . . . . . . . . . . . . . . 168
Heater . . . . . . . . . . . . . . . . . . . . . . . . 163
High Idle System . . . . . . . . . . . . . 165
Oil Pressure Light . . . . . . . . . . . . . . 67 Engine (cont'd)
Overheating . . . . . . . . . . . . . . . . . . 249
Reduced Power Light . . . . . . . . . . . 69
Running While Parked . . . . . . . . 170
Shutdown Warning Light . . . . . . . . 68
Engine Oil Level Indicator Light . . . . . . . . . . . . 67
Engines Diesel Fuel . . . . . . . . . . . . . . . . . . . 218
Exhaust Brake . . . . . . . . . . . . . . . . . . 213
Exhaust Brake Light . . . . . . . . . . . . . 65
Exhaust Fluid Diesel . . . . . . . . . . . . . . . . . . . . . . . . 180
Extender, Seat Belt . . . . . . . . . . . . . . 37
Exterior Lamp Controls . . . . . . . . . . 80
F
Filter . . . . . . . . . . . . . . . . . . . . . . . . . . . . 171 Fuel . . . . . . . . . . . . . . . . . . . . . . . . . . 260
Filter, Engine Air Cleaner . . . . . . . . . . . 243
Fixed Mast Antenna . . . . . . . . . . . . . 90
Flash-to-Pass . . . . . . . . . . . . . . . . . . . . 81
Flashers, Hazard Warning . . . . . . . 82
Flat Tire . . . . . . . . . . . . . . . . . . . . . . . . 300
Fluid Automatic Transmission . . . . . . 241
Brakes . . . . . . . . . . . . . . . . . . . . . . . . 258

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
368 Index
Fluid (cont'd)Power Steering . . . . . . . . . . . . . . . 252
Washer . . . . . . . . . . . . . . . . . . . . . . . 252
Frequency Statement
Radio . . . . . . . . . . . . . . . . . . . . . . . . . 362
Front Seat Position Seats Adjustment . . . . . . . . . . . . . . . . . . . . . 26
Fuel Biodiesel . . . . . . . . . . . . . . . . . . . . . 219
Cold Weather Operation . . . . . . 221
Diesel Engines . . . . . . . . . . . . . . . 218
Economy, Driving for Better . . . 129
Filling the Tank . . . . . . . . . . . . . . . 225
Filter . . . . . . . . . . . . . . . . . . . . . . . . . . 260
Gauge . . . . . . . . . . . . . . . . . . . . . . . . . . 59
Running out of Fuel . . . . . . . . . . . 224
Water in Fuel . . . . . . . . . . . . . . . . . 221
Fuel for Diesel Engines . . . . . . . . . 218
G
Gauges
Diesel Exhaust Fluid (DEF) . . . . . 60
Engine Coolant Temperature . . . 60
Fuel . . . . . . . . . . . . . . . . . . . . . . . . . . . . 59
Odometer . . . . . . . . . . . . . . . . . . . . . . . 58
Speedometer . . . . . . . . . . . . . . . . . . . 58
Tachometer . . . . . . . . . . . . . . . . . . . . . 59
Trip Odometer . . . . . . . . . . . . . . . . . . 58 Gauges (cont'd)
Warning Lights and
Indicators . . . . . . . . . . . . . . . . . . . . . 56
General Information
Vehicle Care . . . . . . . . . . . . . . . . . . 230
Getting In and Out of the Vehicle . . . . . . . . . . . . . . . . . . . . . . . . . 17
Glove Box . . . . . . . . . . . . . . . . . . . . . . . 43
GM Mobility Reimbursement Program . . . . . . . . . . . . . . . . . . . . . . . 358
H
Hazard Warning Flashers . . . . . . . . 82
HeadlampsAiming . . . . . . . . . . . . . . . . . . . . . . . . 267
Bulb Replacement . . . . . . . 267, 270
Daytime Running Lamps(DRL) Indicator Light . . . . . . . . . . 69
Flash-to-Pass . . . . . . . . . . . . . . . . . . . 81
High-Beam On Light . . . . . . . . . . . . 69
High/Low Beam Changer . . . . . . . 81
Heated Mirrors . . . . . . . . . . . . . . . . . . . 22
Heater Engine . . . . . . . . . . . . . . . . . . . . . . . . 163
Heating . . . . . . . . . . . . . . . . . . . . . . . . . 121
High Idle System . . . . . . . . . . . . . . . 165
High-Beam On Light . . . . . . . . . . . . . 69
Hill and Mountain Roads . . . . . . . . 141 Hooks
Shopping Bag . . . . . . . . . . . . . . . . . . 45
Horn . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 53
HVAC . . . . . . . . . . . . . . . . . . . . . . . . . . . 121
I
Idle Shutdown . . . . . . . . . . . . . . . . . . 164
Idle Shutdown Light . . . . . . . . . . . . . 68
Ignition Positions . . . . . . . . . . . . . . . 157
Information Publication Ordering . . . . . . . . . . 362
Information on Loading the
Vehicle . . . . . . . . . . . . . . . . . . . . . . . . . 46
Instrument Cluster . . . . . . . . . . . . . . . 57
Instrument Panel Storage Area . . . . . . . . . . . . . . . . . . . 43
Instrument Panel
Overview . . . . . . . . . . . . . . . . . 8, 10, 11
Introduction . . . . . . . . . . . . . . . . . . . . . . . 2
J
Jump Starting - North America . . . . . . . . . . . . . . . . . . . . . . . 301
K
Keyless EntryRemote (RKE) System . . . . . . . . . 14
Keys . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13