
Chevrolet Low Cab Forward Owner Manual (GMNA-Localizing-U.S.-
11254764) - 2018 - crc - 12/5/16
Instruments and Controls 77
booster (HBB) becomes faulty. The
warning buzzer will stop sounding
when the parking brake is engaged.
On 4500HD and 4500XD, the brake
low vacuum warning light and
warning buzzer should come on to
indicate low vacuum reserve for
brake power assist. At the same
time, the Back up Electric Vacuum
Pump operates.
(5500HD, 5500XD models) When
the HBB pressure is low, and/or the
HBB fluid (Dexron–VI) level is low,
the light and warning buzzer should
come on. Do not use brake fluid in
the brake booster reservoir. Use
only Dexron –VI ATF.
If this happens while driving:
. Do not pump the brakes. The
system is designed to stop the
truck with reserve power assist if
the pedal is held down. This
reserve is greatly reduced each
time you apply and release the
brakes.
. Stopping distance may be
longer. .
You may have to push much
harder on the brake pedal.
. Have the vehicle repaired before
you continue driving.
The buzzer stops when the selector
lever is shifted to the P position.
{Warning
Do not drive while the buzzer
sounds as the brakes are not
operating to their full capacity.
You and others could be seriously
injured.
Antilock Brake System
(ABS) Warning Light
This light comes on briefly when the
engine control switch is turned to
the ON position, and then should go
out after approximately three seconds. If the light does not
come on, have it fixed so it will be
ready to warn if there is a problem.
This warning light comes on
together with the brake system
warning light whenever there is a
problem in the Anti-lock Brake
System (ABS). In this case, the ABS
stops working but the brakes still
function as ordinary service brakes.
{Warning
If this warning light comes on
while driving, immediately stop
your vehicle at a safe place well
clear of traffic and take the
following actions.
1. Stop the engine.
2. Restart the engine. Check ifthe ABS warning light
comes on and then goes
out. If it does, there is no
problem. The ABS operates
normally.
(Continued)

Chevrolet Low Cab Forward Owner Manual (GMNA-Localizing-U.S.-
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288 Vehicle Care
Danger (Continued)
at least 5 minutes. Following this,
you should seek medical
assistance.
When using tools or other metal
objects in the vicinity of the
battery, take care to prevent them
from coming into contact with the
positive terminal. As the vehicle
itself will conduct electricity, any
such contact can result in a
short-circuit and a highly
dangerous electric shock.
A vehicle battery generates
extremely flammable hydrogen
gas. For this reason, operations
producing sparks or requiring the
usage of an open flame must
never be carried out near a
vehicle battery. Failure to observe
this precaution can result in
explosion if the hydrogen gas
ignites. Whenever wiping up
battery fluid, a damp cloth should
be used.(Continued)
Danger (Continued)
Batteries produce explosive
gases, contain corrosive acid,
and supply levels of electrical
current high enough to cause
burns. Therefore, to reduce the
risk of personal injury when
working near a battery:
. Always shield your eyes
and avoid leaning over a
battery whenever possible.
. Do not expose a battery to
open flames or sparks.
. Do not allow battery acid to
contact eyes or skin. Flush
any contacted area with
water immediately and
thoroughly, and get
medical help.
. Follow each step in the
jump starting instructions.
Always stop the engine whenever
the battery is to be inspected. (Continued)
Danger (Continued)
Dilute sulfuric acid is used as the
battery fluid. Special care must be
taken to ensure that this fluid
does not come into contact with
skin, clothing, or metal surfaces.
When disconnecting the cables
from the terminals, start with the
negative terminal. When
connecting them, the negative
terminal should be
reconnected last.
You and others could be seriously
injured.

Chevrolet Low Cab Forward Owner Manual (GMNA-Localizing-U.S.-
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292 Vehicle Care
into contact with the horns or the
bumper. (If towing chains contact
the bumper, then remove the
bumper.)
1. Horns
2. Bumper
After Towing
After towing the vehicle, block the
rear wheels and install axle shafts
or driveshaft.
Apply the parking brake before
disconnecting from the towing
vehicle.Front End Towing (All Wheels On
the Ground)
Your vehicle may be towed on all
wheels provided the steering is
operable. Remember that power
steering and brakes will not have
power assist. There must be a tow
bar installed between the tow
vehicle and the disabled vehicle.
Towing with all wheels on the
ground
1. Bumper
2. Tow Hook
3. Front Axle
4. Towing Guide
5. Towing Chain
To prepare a disabled vehicle for
front end towing with all wheels on
the ground, the following steps are
necessary:
.Block the rear wheels of the
disabled vehicle.
. Disconnect the driveshaft at the
rear axle. Secure the driveshaft
to the frame or crossmember.
When towing, disconnect the
driveshaft at the rear axle to ensure
the transmission is not damaged.
The rear end of the driveshaft must
be disconnected and safely secured
if the 80 km (50 mi) or 48 km/h
(30 mph) is exceeded.
Provide wood blocking to prevent
towing chains and bar from coming
into contact with the bumper.
If there is damage or suspected
damage to the rear axle, remove the
axle shafts.
Cover the hub openings to prevent
the loss of lubricant or entry of dirt
or foreign objects.

Chevrolet Low Cab Forward Owner Manual (GMNA-Localizing-U.S.-
11254764) - 2018 - crc - 12/5/16
Index 351
IndexA
Accessories and Modifica-tions . . . . . . . . . . . . . . . . . . . . . . . . . . 218
Add-On Electrical Equipment . . . 215
Additional Maintenance and Care . . . . . . . . . . . . . . . . . . . . . . 323
Adjustments Seat, Initial Drive . . . . . . . . . . . . . . . 38
Agreements Trademarks and License . . . . . .114
Air Cleaner/Filter, Engine . . . . . . . 231
Air Conditioning . . . . . . . . . . . . . . . . 115
Air Filter, Passenger Com- partment . . . . . . . . . . . . . . . . . . . . . . 119
Air Vents . . . . . . . . . . . . . . . . . . . . . . . 118
AM-FM Radio . . . . . . . . . . . . . . . . . . . . 97
Antenna Fixed Mast . . . . . . . . . . . . . . . . . . . 102
Antilock Brake System (ABS) . . . 196
Warning Light . . . . . . . . . . . . . . . . . . . 77
Appearance Care Exterior . . . . . . . . . . . . . . . . . . . . . . . 293
Interior . . . . . . . . . . . . . . . . . . . . . . . . 299
Ashtrays . . . . . . . . . . . . . . . . . . . . . . . . . 68
Assistance Program,
Roadside . . . . . . . . . . . . . . . . . . . . . . 344
Audio Players CD . . . . . . . . . . . . . . . . . . . . . . . . . . . 103 Automatic
Transmission . . . . . . . . . . . . . . . . . 185
Transmission Fluid . . . . . . . . . . . 229
Automatic Transmission Selector Lever . . . . . . . . . . . . . . . . 194
Shift Lock Control FunctionCheck . . . . . . . . . . . . . . . . . . . . . . . 251
Automatic Transmission Fluid Temperature Warning Light . . . . . 78
Automatic Transmission Overdrive Off . . . . . . . . . . . . . . . . . . 195
Auxiliary Devices . . . . . . . . . . . . . . . . . . . . . . . .113
Axle, Rear . . . . . . . . . . . . . . . . . . . . . . 249
B
Battery . . . . . . . . . . . . . . . . . . . . . . . . . 247
Battery - North America . . . . . . . . . 287
Battery Warning Light . . . . . . . . . . . . 73
Biodiesel . . . . . . . . . . . . . . . . . . . . . . . 207
Blade Replacement, Wiper . . . . . 252
Brake Exhaust . . . . . . . . . . . . . . . . . . . . . . 201
System Warning Light . . . . . . . . . . 75
Brakes . . . . . . . . . . . . . . . . . . . . . . . . . . 242 Antilock . . . . . . . . . . . . . . . . . . . . . . . 196
Exhaust Light . . . . . . . . . . . . . . . . . . . 78
Fluid . . . . . . . . . . . . . . . . . . . . . . . . . . 246
Parking . . . . . . . . . . . . . . . . . . . . . . . 200

Chevrolet Low Cab Forward Owner Manual (GMNA-Localizing-U.S.-
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356 Index
Proposition 65 Warning,California . . . . . . . . . . . . . . . . . 218, 287
R
Radio Frequency Statement . . . . 348
Radio Reception . . . . . . . . . . . . . . . . 101
Radios
AM-FM Radio . . . . . . . . . . . . . . . . . . . 97
Rear Axle . . . . . . . . . . . . . . . . . . . . . . . 249
Rear Seats . . . . . . . . . . . . . . . . . . . . . . 42
Rear Storage . . . . . . . . . . . . . . . . . . . . 57
Recommended Fluids and Lubricants . . . . . . . . . . . . . . . . . . . . . 326
Reduced Engine Power Light . . . . 81
Reimbursement Program, GM Mobility . . . . . . . . . . . . . . . . . . . 344
Remote Keyless Entry (RKE)
System . . . . . . . . . . . . . . . . . . . . . . . . . 26
Replacement Parts Maintenance . . . . . . . . . . . . . . . . . . 328
Reporting Safety Defects
General Motors . . . . . . . . . . . . . . . 349
U.S. Government . . . . . . . . . . . . . 349
Roads Driving, Wet . . . . . . . . . . . . . . . . . . 132
Roadside Assistance
Program . . . . . . . . . . . . . . . . . . . . . . . 344
Roofmarker Lamps . . . . . . . . . . . . . 261
Rotation, Tires . . . . . . . . . . . . . . . . . . 284 Routing, Engine Drive Belt . . . . . . 341
Running out of Fuel . . . . . . . . . . . . . 212
Running the Vehicle While
Parked . . . . . . . . . . . . . . . . . . . . . . . . 160
S
Safety Defects ReportingGeneral Motors . . . . . . . . . . . . . . . 349
U.S. Government . . . . . . . . . . . . . 349
Safety System Check . . . . . . . . . . . . 49
Scheduling Appointments . . . . . . . 345
Seat Belts . . . . . . . . . . . . . . . . . . . . . . . 43 Care . . . . . . . . . . . . . . . . . . . . . . . . . . . . 49
Extender . . . . . . . . . . . . . . . . . . . . . . . . 49
Lap Belt . . . . . . . . . . . . . . . . . . . . . . . . 48
Reminders . . . . . . . . . . . . . . . . . . . . . . 73
Three-Point . . . . . . . . . . . . . . . . . . . . . 45
Use During Pregnancy . . . . . . . . . . 47
Seats Position, Front . . . . . . . . . . . . . . . . . . 38
Rear . . . . . . . . . . . . . . . . . . . . . . . . . . . . 42
Security Vehicle . . . . . . . . . . . . . . . . . . . . . . . . . 33
Selector Lever . . . . . . . . . . . . . . . . . . 194
Service . . . . . . . . . . . . . . . . . . . . . . . . . 120 Accessories and Modifica-
tions . . . . . . . . . . . . . . . . . . . . . . . . 218
Climate Control System . . . . . . . .115
Doing Your Own Work . . . . . . . . 218 Service (cont'd)
Publications Ordering Infor-
mation . . . . . . . . . . . . . . . . . . . . . . 347
Scheduling Appointments . . . . . 345
Transmission Warning Light . . . . 78
Vehicle Soon Light . . . . . . . . . . . . . . 74
Shift Lock Control Function Check, Automatic Trans-
mission . . . . . . . . . . . . . . . . . . . . . . . . 251
Shopping Bag Hooks . . . . . . . . . . . . 58
Sidemarker Lamps . . . . . . . . . . . . . 261
Signals, Turn and Lane-- Change . . . . . . . . . . . . . . . . . . . . . . . . 94
Specifications and Capa-
cities . . . . . . . . . . . . . . . . . . . . . . . . . . 335
Speedometer . . . . . . . . . . . . . . . . . . . . 71
Starting and Stopping the Vehicle . . . . . . . . . . . . . . . . . . . . . . . . 149
Steering . . . . . . . . . . . . . . . . . . . . . . . . 131 Fluid, Power . . . . . . . . . . . . . . . . . . 240
Wheel Adjustment . . . . . . . . . . . . . . 65
Stoplamps and Back-up Lamps Bulb Replacement . . . . . . . . . . . . 263
Storage Rear . . . . . . . . . . . . . . . . . . . . . . . . . . . . 57
Storage Areas Glove Box . . . . . . . . . . . . . . . . . . . . . . 55