wheel CHEVROLET LOW CAB FORWARD 2018 Service Manual

Chevrolet Low Cab Forward Owner Manual (GMNA-Localizing-U.S.-
11254764) - 2018 - crc - 12/5/16
220 Vehicle Care
contamination, it will cause a
decline in the performance of the
parts and such problems as seizure
or malfunctioning. Replenish or
change these liquids when
performing the checks (daily and
periodic checks) as required by the
relevant regulations or in
accordance with the Maintenance
Schedule (when either the specified
driving distance or period of time,
whichever comes first, has expired).
Confirm that all systems and
components are normal after
performing the work.
Do not leave the removed parts or
tools in the engine compartment.
They could damage the equipment if
caught in the belts or other moving
components.
Dirty water, dirt and other impurities
seriously impair the effectiveness of
the oil, grease and fluids, and
damage the parts. Exercise all due
caution to prevent waste or other
refuse from coming in contact with
parts or materials that have been
removed when changing or
replenishing them.Do not step on the engine or climb
onto it. You could cause an engine
failure by, for example, damaging
the cylinder head cover or various
connectors.
Electric Welding
Careless electric welding of vehicle
parts can cause welding current to
flow back through the vehicle’s
ground circuit and damage electrical
and electronic parts so that they do
not function normally. Whenever
electric welding is necessary,
consult your dealer.
Cab Tilting
Before Tilting the Cab (Single Cab
Model)
{Warning
To help avoid personal injury and
property damage:
(Continued)
Warning (Continued)
.Park the vehicle on level
ground and check that there
is enough space in front of
and above the cab.
. Set the parking brake firmly
and block the front wheels.
. Move the selector lever in
the "P" position.
. Secure loose articles in
the cab.
. Stop the engine.
. Close the cab door.
. Keep the area surrounding
the cab clear.
You and others could be seriously
injured.
Tilting the Cab 1. Check that all personnel are clear of the cab.
2. Read the label on the rear of the cab.

Chevrolet Low Cab Forward Owner Manual (GMNA-Localizing-U.S.-
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234 Vehicle Care
radiator or heater core. In particular,
use of coolants containing borate
salts or silicates may result in
engine or radiator corrosion,
causing engine coolant leaks and
other problems.
To dilute the coolant, use distilled
water or deionized water.
Do not use the coolant at any
coolant concentration other than
that specified. If the coolant
concentration is 60% or higher,
overheating is likely to occur, while
if it is 30% or lower, anti-corrosion
function is not provided sufficiently.
Using coolant at any coolant
concentration other than that
specified may reduce anti-freezing
performance, and engine coolant
may freeze.
If the engine coolant decreases
rapidly, go immediately to the
nearest dealer for a check and
repair.Checking the Engine Coolant
Level
For the single cab model, the
engine coolant reserve tank is
located behind the front-right wheel.
SeeCab Tilting 0220.
For the crew cab model, the engine
coolant reserve tank is under the
access panel beneath the left rear
seat. See Engine Cover 0222.
When the engine has cooled down,
make sure that the fluid level in the
engine coolant reserve tank is no
lower than the “MIN”line. In
addition, carefully remove the
radiator cap and check to see if it is
damaged. Check that the engine
coolant is full to the filler neck.
Check the engine coolant level only
when it is cold.

Chevrolet Low Cab Forward Owner Manual (GMNA-Localizing-U.S.-
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Vehicle Care 243
utilizes hydraulic pressure from the
HBB pump integral with the power
steering pump.
If the brake booster warning light
comes on or a warning buzzer
continues to sound, there may be a
problem with the HBB.
If this warning light comes on while
driving, immediately stop your
vehicle at a safe place well clear of
traffic and promptly contact the
nearest dealer for inspection.
Hydraulic brake booster (HBB)
characteristics
In the 5500HD, 5500XD models, an
unusual sound from under the
instrument panel may be heard from
the hydraulic system while brakes
are used. It does not mean trouble.
It is not a sign of malfunction.
If you pump the brakes with the
engine off, a squeaking sound can
be heard. This comes from the
auxiliary accumulator. It is not a
malfunction. With the engine
running, a similar sound can be
heard during sudden braking.Another characteristic of the HBB
system is that the brake pedal may
be pressed easily to the floor with
the vehicle at a stop. This is not a
sign of malfunction.
When the engine is running, the
system automatically charges the
accumulator whenever pressure has
been reduced after braking. Auto
charge may be activated without
braking, depending on temperature
changes in the accumulator. During
auto charge, a hissing and clicking
sound can be heard. This is not a
malfunction.
With the engine running, a booming
sound can be heard during hard
braking. This comes from the
brake-fluid pump. It is not a
malfunction.
Applying continuous hard braking
for a long time will lead to
considerable temperature rise in the
HBB pump. Such overworking of the
brakes is best avoided.
Vacuum or hydraulic power
assisted brakes
If the engine stops, do not pump the
brakes. The system is designed to
stop the vehicle with reserve power
assist if the brake pedal is held
down. This reserve is greatly
reduced each time you apply and
release the brakes. If, when you
turn the steering wheel during
braking, the vehicle does not turn,
release some pressure from the
brake pedal.
In a Vehicle Equipped with an
HBB, Do Not Keep the Brake
Pedal Pressed for an Extended
Period
Caution
Failure to follow the above
instruction will cause the oil inside
the HBB oil pump to get very hot.
This could damage the HBB tank
and deteriorate seals and also
could cause damage to the HBB
oil pump, HBB unit and/or HBB
(Continued)

Chevrolet Low Cab Forward Owner Manual (GMNA-Localizing-U.S.-
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244 Vehicle Care
Caution (Continued)
hosing. Eventual leakage of HBB
oil, sudden increase in brake
pedal resistance and fire could
unexpectedly result in an
accident.
Hydraulic Brake Booster (HBB)
Fluid (5500HD/5500XD Series)
The HBB system has been
designed to use Dexron VI ATF
fluid. If any other fluid is used with
this system, rubber components
may be damaged, oil may leak and
the system may malfunction. It is
important to remember that the fluid
used in the hydro-booster is
completely different in
characteristics from the brake fluid
used in the master and wheel
cylinders.
If hydro-booster fluid and brake fluid
from the master cylinder are
mistakenly mixed together and
used, rubber components will
deteriorate as a result of insufficient
lubrication. Any resultant oil leakage or system malfunction can in turn
lead to dragging brakes or other
major brake problems. As such,
mixing of these two fluids can
ultimately lead to vehicle fire or
other serious accidents.
When the pump operates while the
engine is running, the fluid in the
hydro-booster will become hot.
During normal braking, the
temperature in piping and within
the hydro-booster can rise above
100 °C (212 °F). For this reason,
special care will be required when
working with hydro-booster
components. If the hydro-booster is
to be removed from the vehicle,
shut off the engine and then allow at
least 30 minutes for it to cool down
before beginning this operation.
Even when the engine is stopped,
the hydro-booster's accumulator will
remain in a highly-pressurized
condition for a significant period of
time. Before removing the
hydro-booster or piping from the
vehicle, stop the engine and press
the brake pedal at least 10 times in
order to lower the accumulator
pressure to atmospheric pressure.This is of particular importance
when removing components such
as the accumulator or pressure
switch from the hydro-booster.
If these operations are attempted
while the accumulator is still at a
high pressure, hydro-booster fluid
may spray out.
Checking the Hydro-booster Fluid
Level
Check the hydro-booster fluid level
and change the fluid according to
the Maintenance Schedule.
The hydro-booster fluid level is
correct if it is between the "MAX"
and "MIN" lines. If the level is too

Chevrolet Low Cab Forward Owner Manual (GMNA-Localizing-U.S.-
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246 Vehicle Care
If your vehicle's brakes squeak
during normal driving or braking, the
cause may be one of the following.
‐Brake pad wear
Brake pads are about to wear
out. If this happens, have your
vehicle inspected at the nearest
dealer as soon as possible.
‐ Adherence of sand, grit or mud
If sand, grit or mud adheres to
the brakes, a screeching sound
may be emitted upon contact with
rotating components. If this
happens, wash the vehicle to
remove all such adhering matter.
If cleaning alone does not
eliminate the squeaking sound,
have your vehicle inspected at
the nearest dealer.
Brake Hoses and Pipes
Inspection
With the steering wheel turned fully
to the left, check the left front brake
hose and pipe visually and by
touch, making sure that they are
free of scratches, cracks and
bulging. Also make sure that the hose and pipe do not interfere with
any chassis part or wheel, and that
their joints are not leaking and are
free of any type of damage. Check
the right front brake hose and pipe
in the same way. The rear left and
right brake hoses and pipes should
also be checked in the same
manner.
Disc Brakes and Drum Brakes
If the brake pads and shoe linings
wear out beyond their usable limit,
not only will the brake performance
be impaired, but brake components
could also fail.
{Warning
Do not drive with brake pads and
shoe linings worn out beyond the
limit. Excessively worn brake
pads and shoe linings may cause
breakdown of brake components
and poor braking performance.
You and others could be seriously
injured.
Caution
The pad has an embedded wear
indicator. A squeaking noise from
the indicator means that the pad
is approaching the usable limit.
If the squeaking noise from the
indicator can be heard, contact
the nearest dealer for inspection
or replacement.
Brake Fluid
Checking the Brake Fluid
Level

Chevrolet Low Cab Forward Owner Manual (GMNA-Localizing-U.S.-
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266 Vehicle Care
{Warning
Always use fuses specified for the
vehicle. 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.Replacing Relays
Before replacing the relays, contact
the nearest dealer.
The vehicle may not be equipped
with all of the fuses, relays, and
features shown.
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.

Chevrolet Low Cab Forward Owner Manual (GMNA-Localizing-U.S.-
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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.-
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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.-
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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.-
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276 Vehicle Care
Recommended replacement tire for Greenhouse Gas (GHG) emissions
Tire sizeTire makerTire name Rolling
resistance
LT215/85R16E BRIDGESTONE CORPORATION
Duravis R250 LRRA
THE YOKOHAMA RUBBER CO., LTD. TY213A MC2 LRRA
225/70R19.5F BRIDGESTONE CORPORATION
M895Z LRRA
THE YOKOHAMA RUBBER CO., LTD. TY287 MC2 LRRA
If the original equipment tires are
low rolling tires, it is recommended
to use the LRRA tires shown in the
above table.
Refer to the emission control
identifiers on Greenhouse Gas
(GHG) emission plate for your
original equipment tires. Also,
please refer to “VIN, Weight Rating,
and Greenhouse Gas (GHG)
Emissions Plate” for the location of
the Greenhouse Gas (GHG)
emission plate. See Vehicle
Identification Number (VIN) 0330. Wheel Replacement
Recommendations
Wheels must be replaced if they
become damaged (for example:
bent, heavily rusted, leak air) or if
wheel nuts often become loose. Do
not use bent wheels that have been
straightened and do not use inner
tubes in leaking wheels which are
designed for tubeless tires. Such
wheels may have structural damage
and could fail without warning.
When replacing wheels for any
reason, the new wheels should be
equal in load capacity, diameter,
width, offset and mounting types to
those originally installed in your
vehicle. A wheel of the wrong size or type
may adversely affect wheel and
bearing life, brake cooling,
speedometer/odometer calibration,
stopping ability, headlight aim,
bumper height, vehicle ground
clearance and tire or tire chain
clearance on the body and chassis.
Replacement with "used" wheels is
not advised. They may have been
subjected to harsh treatment or very
high mileage and could fail without
warning.