tires CHEVROLET LOW CAB FORWARD 2018 User Guide

Chevrolet Low Cab Forward Owner Manual (GMNA-Localizing-U.S.-
11254764) - 2018 - crc - 12/5/16
196 Driving and Operating
Overdrive Off Indicator Light
Indicator lightFunction Usage conditions
Goes Off. 6-Speed (4-speed + overdrive) automatic
change (Overdrive ON). Use under normal driving conditions.
Comes On. 4-speed automatic change, but no change to
overdrive (overdrive OFF). Used when a light engine brake is required.
Doing so will reduce the number of gear
changes making the ride smoother on roads
that have many hills.
. During cold weather, the
transmission may not shift to the
5th or 6th gear (overdrive) until
the engine warms up.
. Even if the engine is stopped
with the overdrive OFF, the
overdrive will be ON the next
time the engine is started.
Brakes
Antilock Brake
System (ABS)
Wheels may be locked and slip
during sudden braking or braking on
a slippery road surface such as a
snowy road. ABS is a device to
prevent the wheels from locking by
detecting a slippery condition during
braking and securing the directional
stability and handling stability of the
vehicle. ABS only assists in limited
road conditions and will not prevent
an accident if you exceed safe
driving speeds for road conditions.
Always drive safely.
{Warning
The braking distance on slippery
road surfaces is longer than that
on a normal dry paved road even
with an ABS-equipped vehicle. In
addition the braking distance can
be slightly longer in deep snow
and on a gravel road when ABS
is activated. Therefore, always
keep in mind the road condition
and tire condition (type of tires
and worn condition), observe safe
driving habits and drive the
vehicle while keeping a proper
distance between vehicles.
(Continued)

Chevrolet Low Cab Forward Owner Manual (GMNA-Localizing-U.S.-
11254764) - 2018 - crc - 12/5/16
Driving and Operating 197
Warning (Continued)
ABS does not prevent accidents if
you do not drive safely. Drive the
vehicle at a safe speed.
Install tires of the specified size,
same brand and same tread
design (including winter tires) on
all wheels. If different tires are
installed, the braking distance
becomes longer and directional
control stability of the vehicle
decreases. This is very
dangerous.
Steering during sudden braking
(when the ABS is working) will
feel slightly different than it does
when the brakes are not applied.
Operate the steering wheel
carefully keeping this in mind.
Driving in sand or on a muddy road
may adversely affect the brakes and
ABS sensors. Wash the vehicle to
remove sand and mud after
operating the vehicle in sandy or
muddy conditions. Before washing the vehicle, provide
necessary protection to prevent
water from being splashed on the
ABS components (sensors and
actuators). Especially when using
high-pressure washing, be careful
not to allow water to be directly
sprayed onto the ABS components
and their harness connectors.
These are not signs of ABS
malfunction:
.
Soon after you start the engine
and the vehicle starts moving,
the sound of motor or valve
working may be heard from the
rear of the vehicle or underside
of the cab. This sound is from a
self-check by the ABS system
and is normal. In addition, you
may also feel some vibration if
the brake pedal is pressed at
this time.
. When ABS is operating,
vibration is felt on the brake
pedal and steering wheel and
you may hear the system
operating. This is normal when
ABS is properly operating. .
The exhaust brake may release
when ABS is activated and the
exhaust brake is in operation.
. ABS is more likely to be
activated when the brake is
applied during cornering or
driving over a bump. This is
because inside wheels or
wheels that have gone over a
bump tend to lock.
. ABS is not activated immediately
after starting the vehicle. It is
activated only when the vehicle
speed reaches approx. 10 km/h
(6 MPH). ABS operation is
inactive when the vehicle speed
reduces to approx. 5 km/h
(3 MPH).

Chevrolet Low Cab Forward Owner Manual (GMNA-Localizing-U.S.-
11254764) - 2018 - crc - 12/5/16
Driving and Operating 199
Warning (Continued)
‐When driving over road
joints or bumps such as
light reflectors on the road.
‐ When driving on a bumpy
road, stone-paved road or
track.
‐ When driving over an iron
plate or manhole lid.
ABS does not work for wheel skid
during a standing start,
acceleration and cornering which
do not involve braking. On a very
slippery icy road, tires may lose
grip and steering wheel operation
may not be able to control the
vehicle's direction, resulting in
very unstable driving. Always
drive the vehicle observing a safe
speed well matched with both
road surface and tire conditions,
and avoid sudden braking.
If powerful engine braking is
applied on a very slippery icy
road, the drive wheels may be (Continued)
Warning (Continued)
locked (the ABS then does not
work), resulting in loss of vehicle
control.
When ABS is activated, a slight
vibration (especially when the
road surface is different between
right and left wheels) and pulling
may be felt on the brake pedal
and steering wheel. In addition,
an operating sound is produced
from the ABS actuators. This
does not indicate any abnormal
condition. Stay calm and operate
the steering wheel properly.
Electronic Braking force
Distribution (EBD)
EBD is a function that uses the ABS
to distribute braking force ideally
between the front and rear wheels
in order to compensate for changes
in load conditions or any shift of the
load due to acceleration or
deceleration, thus preventing
premature locking of the rear
wheels.
{Warning
If a problem should occur with the
EBD function, the ABS warning
light and the brake system
warning light will come on
simultaneously.
The rear wheels will lock more
easily if there is a problem with
the EBD function. Have it
checked and serviced at the
nearest dealer as soon as
possible. You and others could be
seriously injured.
When the EBD operates, the brake
pedal may push back slightly or you
may hear a sound similar to that
generated by the ABS when
operational. Neither of them
indicates any abnormal condition.

Chevrolet Low Cab Forward Owner Manual (GMNA-Localizing-U.S.-
11254764) - 2018 - crc - 12/5/16
Driving and Operating 201
Inspection
Pull the parking brake lever slowly
from the fully released position while
counting the clicks produced as the
lever engages ratchet plate notches
to check that it can be raised the
proper amount and the lever is held
firmly.
If the number of notches is not
within the standard value range
below, adjust it to the standard
value. Lever stroke is 6 to 8
notches.
Number of notches before parking
brake is set when lever is pulled
slowly from released position withpull force of about 147 N
(15 kgf/33 lbs).
See
Maintenance Schedule 0303
and Additional Maintenance and
Care 0323.
Exhaust Brake
Exhaust Brake Switch
When turned on, the system
increases the amount of power
absorbed by the engine while
coasting in gear. Whenever slowing
down the vehicle, such as on down
grades, in city traffic or approaching
stop signals, this brake system may
be used.
To turn on the exhaust brake system
while driving, pull the lever
backward. The exhaust brake
indicator light comes on. The
exhaust brake will engage
automatically when the accelerator
pedal is released and vehicle speed
is above 10 km/h (6.5 MPH).
The exhaust brake will disengage
when the accelerator pedal or brake
pedal is pressed. Releasing the
pedal reengages the exhaust brake.
Push the lever forward to turn the
exhaust brake off during idling.
{Warning
It is extremely dangerous to apply
the exhaust brake on slippery
roads as the tires can skid.
You and others could be seriously
injured.

Chevrolet Low Cab Forward Owner Manual (GMNA-Localizing-U.S.-
11254764) - 2018 - crc - 12/5/16
Vehicle Care 217
Vehicle Care
General Information
General Information . . . . . . . . . . 218
California Proposition65 Warning . . . . . . . . . . . . . . . . . 218
California Perchlorate Materials Requirements . . . . . 218
Accessories and Modifications . . . . . . . . . . . . . . . . 218
Vehicle Checks
Doing Your OwnService Work . . . . . . . . . . . . . . . 218
Cab Tilting . . . . . . . . . . . . . . . . . . . . 220
Engine Compartment Overview . . . . . . . . . . . . . . . . . . . . 222
Engine Cover . . . . . . . . . . . . . . . . . 222
Engine Oil . . . . . . . . . . . . . . . . . . . . 223
Automatic Transmission Fluid . . . . . . . . . . . . . . . . . . . . . . . . 229
Engine Air Cleaner/Filter . . . . . . 231
Engine Coolant . . . . . . . . . . . . . . . 231
Engine Overheating . . . . . . . . . . 237
Power Steering Fluid . . . . . . . . . 240
Washer Fluid . . . . . . . . . . . . . . . . . 241
Brakes . . . . . . . . . . . . . . . . . . . . . . . 242
Brake Fluid . . . . . . . . . . . . . . . . . . . 246
Battery . . . . . . . . . . . . . . . . . . . . . . . . 247
Fuel Filter . . . . . . . . . . . . . . . . . . . . 248 Rear Axle (Gear Oil Viscosity
Chart) . . . . . . . . . . . . . . . . . . . . . . . 249
Rear Axle (Oil Level Check) . . . . . . . . . . . . . . . . . . . . . . 249
Noise Control System . . . . . . . . 250
Automatic Transmission Shift
Lock Control Function
Check . . . . . . . . . . . . . . . . . . . . . . . 251
Wiper Blade Replacement . . . . 252
Headlamp Aiming
Headlamp Aiming . . . . . . . . . . . . 254
Bulb Replacement
Bulb Replacement . . . . . . . . . . . . 254
Headlamps and Front Turn Signal . . . . . . . . . . . . . . . . . . . . . . . 257
Roofmarker Lamps . . . . . . . . . . . 261
Sidemarker Lamps (Including Turn Signal and Cornering
Lamps) . . . . . . . . . . . . . . . . . . . . . . 261
Taillamps, Turn Signal, Stoplamps, and Back-Up
Lamps . . . . . . . . . . . . . . . . . . . . . . 263
License Plate Lamp . . . . . . . . . . 263
Interior Lamps . . . . . . . . . . . . . . . . 264
Electrical System
Electrical System Overload . . . 264
Wheels and Tires
Wheels and Tires . . . . . . . . . . . . . 272 Tire Pressure . . . . . . . . . . . . . . . . . 284
Tire Rotation . . . . . . . . . . . . . . . . . 284
If a Tire Goes Flat . . . . . . . . . . . . 287
Jump Starting
Jump Starting - North
America . . . . . . . . . . . . . . . . . . . . . 287
Towing the Vehicle
Towing the Vehicle . . . . . . . . . . . 291
Appearance Care
Exterior Care . . . . . . . . . . . . . . . . . 293
Interior Care . . . . . . . . . . . . . . . . . . 299

Chevrolet Low Cab Forward Owner Manual (GMNA-Localizing-U.S.-
11254764) - 2018 - crc - 12/5/16
242 Vehicle Care
Follow the instructions provided with
the windshield washer fluid
regarding the ratio for mixing with
tap water.
Poor quality products, engine
coolant, and soapy water must not
be used. Failure to observe this
precaution can result in nozzle
blockage or damage to painted
surfaces.
The washer should never be used
while the tank is empty. Operating
the washer with the tank empty can
result in motor damage.
Brakes
For the most effective braking and
for maximum life from brake system
components, follow these
suggestions:
.Keep any obstructions from
interfering with brake pedal
travel.
. Keep tires properly inflated.
Improperly inflated tires can
reduce the efficiency of the
brakes. Follow the recommendations for
brake checks in the Maintenance
Schedule.
GM replacement brake lining
material is recommended for this
vehicle to maintain the balance
between front and rear brake
performance. GM replacement
brake parts have been carefully
selected to provide the proper brake
balance for purposes of both
stopping distance and controllability
over the full range of operating
conditions. Installation of front or
rear brake lining material with
performance different from that of
the replacement parts
recommended for this vehicle can
change the intended brake balance
of this vehicle.
Checking the Brake Electric
Vacuum Pump (4500HD/
4500XD Series)
1. Turn the engine control switch
to the "ON" position (do not
start the engine), and press the
brake pedal several times. 2. Check for the noisy sound of
the electric vacuum pump
inside the instrument panel at
the same time as vacuum
warning buzzer sound, and
check that the brake low
vacuum warning light
comes on.
3. Then, start the engine. The main vacuum pump driven by
the engine will start running.
If the electric vacuum pump
operation (noisy sound) and
the vacuum warning buzzer
stop, and the brake low
vacuum warning light goes off
thereafter, the operation is
normal.
4. If you cannot hear the noisy sound or the noisy sound stays
on all the time, have the
vehicle inspected by the
nearest dealer immediately.Hydraulic Brake Booster (HBB)
The 5500HD, 5500XD models are
equipped with an HBB system. HBB
is a brake booster device that

Chevrolet Low Cab Forward Owner Manual (GMNA-Localizing-U.S.-
11254764) - 2018 - crc - 12/5/16
272 Vehicle Care
{Warning
Always use fuses specified by the
dealer when replacing the
slow-blow fuse. Using fuses with
a rating other than that specified,
or using wire or tin foil, etc., could
result in fire or damage.
If the new fuses blow right away
and the cause is unknown,
contact your dealer.
Do not inspect or replace fuses
when the starter switch is in the
ON position. Doing so may lead
to an accident.
When inspecting fuses, be sure to
park the vehicle on flat, level
ground and apply chocks to the
wheels.It is not necessary to open or close
the cover unless trouble is found.
The relay box structure makes it
difficult for water to enter. If you
should spill water or a beverage of
the cover, however, wipe it off
before opening the cover.
The area around the cover will get
warm when the vehicle is being
driven, but this is not abnormal.
Wheels and Tires
The operating load and cold inflation
pressure on the rim and wheel must
not exceed the rim and wheel
manufacturer's recommendations
even though the tire may be
approved for a higher load or
inflation. Rim and wheel may be
identified (stamped) with maximum
load and maximum cold inflation
rating. For rims and wheels not so
identified or for service conditions
exceeding the rate capacities,
consult the rim and wheel
manufacturer to determine rim and
wheel capacities for the intended
service. The factory-installed tires
on this vehicle were selected to
provide the best all-around tire
performance for normal operation.
When inflated, as shown on the
vehicle, they have the load carrying
capacity to operate satisfactorily at
all loads up to and including the full
rated load specified for the vehicle.
For more information concerning the
differences in capacities of tires and
rims, refer to the
“Tire and Rim
Association Inc. Yearbook,” or your
authorized dealer or tire dealer.

Chevrolet Low Cab Forward Owner Manual (GMNA-Localizing-U.S.-
11254764) - 2018 - crc - 12/5/16
Vehicle Care 273
Tire Inflation
{Warning
To reduce the risk of loss of
vehicle control and personal
injury:
Tires must be properly inflated,
and your vehicle must not be
overloaded (see the information
onInformation on Loading the
Vehicle 058 and "Tire Load and
Inflation Table" under Tire
Pressure 0284).
Be sure to keep tires properly
inflated. A tire that is run while
seriously underinflated may
overheat to the point where the
tire may lose air suddenly and/or
catch fire, possibly resulting in
personal injury and/or property
damage.
See “Tire Load and Inflation Table”
under Tire Pressure 0284. In no case should the front or rear
tire load exceed the maximum
recommended gross axle weight
rating (front GAWR or rear GAWR).
The efficiency of the vehicle will be
upset if air pressure in the tires are
not equal. Balanced inflation results
when the tires on the same axle
carry the same air pressure.
A difference in pressure between
the front and rear tires may be
permissible within certain limitations,
however, there should not be a
difference in pressures between the
right and left tires on the same axle.
Always use a truck tire pressure
gauge (a pocket-type gauge is not
advised) when checking inflation
pressures. Visual inspection of tires
for inflation pressures is not enough,
especially in the case of radial tires.
Underinflated radial tires may look
similar to correctly inflated radial
tires. If the inflation pressure on a
tire is found to be low frequently,
have your dealer correct the cause.
Be sure to install the tire inflation
valve caps to prevent dirt and
moisture from getting into the valve core, which could cause air leakage.
An underinflated tire in a dual wheel
assembly is harder to notice than
one in a single wheel assembly. The
properly inflated dual tire carries its
own load plus that of the
underinflated tire. Both tires can
overheat, which may result in
property damage and/or personal
injury (see previous WARNING).
Tires Used or Stored for a Long
Period of Time
Tires are a rubber product and
degrade over time, even if they are
not being used. If any of your tires is
5 to 7 years old or more, please
have them inspected for safe
driving. For further information,
please check with the tire
manufacturer.
Dual Tire Operation
The outer tire of a pair on dual
wheel installations generally wears
faster than the inner tire. If this
occurs, reverse the position of the
tires to equalize wear and get better
tire life.

Chevrolet Low Cab Forward Owner Manual (GMNA-Localizing-U.S.-
11254764) - 2018 - crc - 12/5/16
274 Vehicle Care
In addition, when trucks are driven
continuously on high-crown roads,
an increase in air pressure of
35 kPa (5 psi) in the outer tire of a
dual tire operation will prolong outer
tire life. Be sure not to exceed the
inflation pressure limits shown on
the“VIN, Weight Rating, and
Greenhouse Gas (GHG) Emissions
Plate.” SeeVehicle Identification
Number (VIN) 0330.
Wheel and Tire Balancing
Proper tire balancing provides the
best riding comfort and helps to
reduce tire tread wear.
Out-of-balance tires can cause
annoying vehicle vibration and
uneven tire wear, such as cupping
and flat spots. See your authorized
dealer for wheel balancing.
Front End Alignment
Proper front end alignment improves
tire tread mileage. Your vehicle's
front end suspension parts should
be inspected often and aligned
when needed. (See the
Maintenance Schedule for more
information.) Improper alignment will
not cause the vehicle to vibrate; however, improper toe-in alignment
will cause front tires to roll at an
angle that will result in faster tire
wear. Incorrect caster or camber
alignment will cause your front tires
to wear unevenly, and may cause
the vehicle to "pull" to the left or
right.
Tire Traction
A decrease in driving, cornering and
braking traction occurs when water,
snow, ice, gravel or other material is
on the road surface. Driving
practices and vehicle speed should
be adjusted to the road conditions.
When driving on wet or slushy
roads, it is possible for a wedge of
water to build up between the tire
and road surface. This is known as
hydroplaning, and may cause partial
or complete loss of traction, vehicle
control and stopping ability; this
condition is also more likely with
worn tires.
To reduce the chance of traction
loss, follow these tips:
.
Slow down during rainstorms or
when roads are slushy. .
Slow down if the road has
standing water or puddles.
. Replace tires when front tread
depth is 3.2 mm (4/32 in.) and
rear tread depth is 1.6 mm
(2/32 in.).
. Keep tires properly inflated.
Tire Replacement
Recommendations
{Warning
Do not mix different construction
types of tires on your vehicle such
as radial, bias and bias-belted
tires except in emergencies,
because vehicle handling could
be affected and may result in loss
of vehicle control, or personal
injury or death.
Consult your dealer before
replacing wheels. Never use
wheels that are not designed for
the vehicle. Doing so would
impede safe vehicle operation.

Chevrolet Low Cab Forward Owner Manual (GMNA-Localizing-U.S.-
11254764) - 2018 - crc - 12/5/16
Vehicle Care 275
You should replace your tires when:
.Your tires are worn to a point
where 3.2 mm (4/32 in.) (front)
and 1.6 mm (2/32 in.) (rear) or
the cord or fabric is exposed.
. Your tire tread or sidewall is
cracked, cut or snagged deeply
enough to expose the core,
fabric or steel components.
. Your tire has a hump, bulge or
split.
. Your tire sustains a puncture, cut
or other damage that cannot be
correctly repaired because of the
size or location of the damage.
When replacing tires, you should
use the same size, load range and
construction type (bias or radial) as
the original tires on your vehicle.
Use of any other size or type tire
may affect load carrying capacity,
ride, handling, speedometer/
odometer calibration, vehicle ground
clearance and tire clearance to the
chassis. If replacing only a single
tire, it should be put on the same
axle with other tires of equal
diameter. When replacing or rotating tires, all
tires on an axle should be of the
same tread design and should have
the same outside diameter within
certain limitations, particularly on
LSD models. Consult your
authorized dealer or tire dealer.