2018 CHEVROLET LOW CAB FORWARD change wheel

Chevrolet Low Cab Forward Owner Manual (GMNA-Localizing-U.S.-
11254764) - 2018 - crc - 12/5/16
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.-
11254764) - 2018 - crc - 12/5/16
Vehicle Care 281
Damaged Tires
{Danger
It is dangerous to mount the
wrong size tire on a wheel. If you
do so, the tire/wheel can explode
as air is being added. This
explosion may result in severe
personal injury or death. To learn
which wheels and tires are
correct, look at the "VIN, Weight
Rating, and Greenhouse Gas
(GHG) Emissions Plate" on the
left side rear pillar panel below
the striker (single cab) or on the
left center pillar panel beside the
shoulder seat belt anchor (crew
cab). Wheel size is also stamped
on the side of each wheel.
To help avoid personal injury and
property damage if a wheel must
be changed, seek expert tire
services if you can. If you must
remove the wheel without any
such help, do the following:(Continued)
Danger (Continued)
.If the tire looks as if it may
be underinflated, stand to
the side and check whether
the wheel assembly
appears normal by
comparing it to another
wheel assembly on the
vehicle.
. Let the air out of the tire by
taking out the valve core.
If you have a way to put air
back in a tire, note that it is
good safety practice to let
the air out of both tires of a
dual assembly before taking
off the damaged tire and rim
assembly from the vehicle.
After letting out the air, take
off the tire and rim assembly
and install a spare tire and
rim assembly.
If your vehicle is equipped
with a differential lock
system or limited slip
differential (LSD), it might
(Continued)
Danger (Continued)
start moving when the
engine power is transmitted
to the rear axle even when
one of the wheels on the
axle is raised clear of the
ground. Do not start the
engine with any rear wheel
in contact with the ground.
If you are not fully
experienced on the
procedures to follow, and/or
are not equipped with the
proper tools and equipment,
again, do not attempt to
raise the vehicle, or remove
or install the tire and wheel
assembly—seek expert tire
services.
. Do not put air back in a tire
that has been run flat, or is
seriously low on air, without
first having the tire taken off
the wheel and the tire
checked for damage.
(Continued)

Chevrolet Low Cab Forward Owner Manual (GMNA-Localizing-U.S.-
11254764) - 2018 - crc - 12/5/16
Vehicle Care 285
The difference in diameter of the
tires for a dual-tire wheel should be
within the limit specified in the table
below. If the limit is exceeded, the
tires wear more rapidly than they
should.
Steel Wheels
Aluminum/Steel Wheels
Vehicles with the aluminum wheel
option may have steel wheels on
the inner rear position. These
wheels must only be mounted on
the inner rear positions and should
only be rotated from side to side.
{Warning
If differently sized tires are used
between the front and rear axles,
do not exchange tires between
the front and rear axles;
otherwise, the tires get loaded
beyond their limits. This is highly (Continued)
Warning (Continued)
dangerous because the tires and
disc wheels could break down
under an excessive load. You and
others could be seriously injured.
Permissible diameter difference
Radial tire Within 8 mm (0.31 in)
The tightening torque of the wheel
nuts may decrease after a tire
change due to their initial
settlement. Upon driving 50 to
100 km (31 to 62 mi) after a tire
change, retighten the wheel nuts to
the specified torques according to
the instructions in "Retightening
Wheel Nuts" following.
See Maintenance Schedule 0303.
Retightening Wheel Nuts
Check the wheel nuts to make sure
they are tightened to the specific
torque by using a torque wrench.
Use the following methods to check
loose wheel nuts. The tightening
torque of the wheel nuts may

Chevrolet Low Cab Forward Owner Manual (GMNA-Localizing-U.S.-
11254764) - 2018 - crc - 12/5/16
286 Vehicle Care
decrease after a tire change or
rotation due to their initial
settlement. After driving 50 to
100 km (31 to 62 mi), be sure to
retighten the wheel nuts to the
specified torque.
SeeMaintenance Schedule 0303.
Tightening torque
500 N·m (362 lb·ft)
Single Tire
1. Left side tire
2. Right side tire
Turn the wheel nuts in the tightening
direction to the specified torque. Retightening of nuts on left rear
dual-tire wheel
Dual Tire
Of the nuts on the wheel studs,
loosen the outer wheel nuts.
Tighten the inner wheel nuts of the
same wheel to the specified torque.
Next, tighten the outer wheel nuts to
the specified torque.

Chevrolet Low Cab Forward Owner Manual (GMNA-Localizing-U.S.-
11254764) - 2018 - crc - 12/5/16
Vehicle Care 287
{Warning
If you find any abnormal
conditions with the wheel nuts
such as frequent loosening of
retightened nuts, have your
vehicle checked or serviced at the
nearest dealer as soon as
possible.
Fully engage the wheel wrench on a
wheel nut in order to tighten the nut
to the specified torque. However, do
not use a pipe as a handle
extension or your foot to apply force
on the wrench. This would tighten
the nut more than required and
might damage components.
Both under-tightening and
over-tightening of wheel nuts may
cause broken wheel studs or
cracked disc wheels and could lead
to wheel detachment. Adhere to the
specified tightening torques.
When replacing a tire with a new
one, use only a tire of the same
type and size as the replaced tire;
otherwise, driving safety could be affected. Avoid mixed use of
different types or different size tires
at all costs.
If a Tire Goes Flat
When the tire goes flat while driving,
ease off the accelerator pedal, avoid
hard braking, hold on to the steering
wheel firmly, and stop the vehicle.
The tire should be changed in a
safe, open location to prevent
obstructing other vehicles or
pedestrians.
{Warning
If you continue to drive on a flat
tire, undue force will be applied to
the wheel studs, possibly causing
the studs to break and the wheel
to come off. You and others could
be seriously injured.
See “Tire Replacement
Recommendations” underWheels
and Tires 0272.
Jump Starting
Jump Starting - North
America
When the Battery is
Discharged
Use a jumper cable (sold
separately) and the battery of
another vehicle to start the engine in
the following sequence.
{Danger
Follow the precautions listed in
the jump starting instructions
when working on or near the
battery. Personal injury
(particularly to eyes) or property
damage may result from battery
explosion, battery fluid or
electrical (short circuit) burns.
If battery fluid should come in
contact with an eye, immediately
wash away using a large amount
of water and continue washing for
(Continued)

Chevrolet Low Cab Forward Owner Manual (GMNA-Localizing-U.S.-
11254764) - 2018 - crc - 12/5/16
Service and Maintenance 315
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.
21. Brake Fluid :Check the fluid in
the brake fluid reservoir every
16 000 km (10,000 miles). Replace
the fluid every 48 000 km
(30,000 miles).
22. Hydraulic Brake Booster Fluid
(5500HD, 5500XD models) :
Replace Dexron VI ATF fluid every
24 months or 30,000 miles
(48,000 km), whichever occurs first.
23. Brake Line and Hoses : Check
lines and hoses for proper hook-up,
binding, leaks, cracks, chafing, etc.
every 32 000 km (20,000 miles).
Any questionable parts should be
replaced or repaired at once. When
rubbing or wear is noted on lines or
hoses, the cause must be corrected
at once.
24. Parking Brake Cable : Check
the parking brake cable every
16 000 km (10,000 miles) or
12 months whichever occurs first. 25. Automatic Transmission
Fluid :
Check the automatic
transmission fluid level at each
engine oil change and replace fluid
every 48 000 km (30,000 miles). Do
not overfill.
26. Differential Gear Oil : Replace
lubricant every 48 000 km
(30,000 miles). Check lubricant level
every 16,000 km (10,000 miles) or
every 12 months, and add lubricant
to within 0 to 10 mm (0 to 0.4 inch)
of the bottom edge of the filler hole
if necessary.
27. Power Steering Fluid :
Replace power steering fluid every
24 months or 48 000 km
(30,000 miles), whichever occurs
first.
28. Power Steering Oil Hoses :
Replace power steering oil hoses
every 24 months or 80 000 km
(50,000 miles), whichever occurs
first.
29. Steering Wheel Free Play :
Check steering wheel free play after
the first 1 040 km (650 miles) and
then every 10 400 km (6,500 miles). Steering wheel free play
10-50 mm (0.39-1.97 in)
30. Steering Gear Box Torque :
Retighten the attaching bolts of the
steering gear box to the specified
torque every 12 months or every
32 000 km (20,000 miles) whichever
occurs first. Steering gear box tightening torque
103 Y(76 lb·ft)
31. Driveshaft Flange Torque :
Check the fixing bolts of driveshaft
flange for looseness or damage
after the first 16 000 km
(10,000 miles). Driveshaft flange tightening torque
103Y(76 lb·ft)
32. Driveshaft Lubrication :
Lubricate the grease fitting on the
center bearing, as well as each
universal joint and spline coupling
every 12 months or 16 000 km
(10,000 miles) whichever occurs
first.

Chevrolet Low Cab Forward Owner Manual (GMNA-Localizing-U.S.-
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316 Service and Maintenance
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.

Chevrolet Low Cab Forward Owner Manual (GMNA-Localizing-U.S.-
11254764) - 2018 - crc - 12/5/16
Service and Maintenance 323
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 an accident 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 0200 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 0317).
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