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Tread wear indicator (Example)
1. Lug pattern
2. Rib pattern
Using worn-out tires is dangerous
because they might have an
increased chance of getting
punctured or bursting while driving.
Check all tires to see if tread wear
indicators appear on their treads
and also check their entire tread for
its depth with a depth gauge to
make sure that the grooves are
deeper than the specified depth.
A tire with tread wear indicators
appearing must be changed. Also,
check the tires for uneven or
otherwise abnormal wear.
{Warning
Tires with excessively shallow
tread grooves will increase the
chance of skidding and, when
driving at high speeds,
hydroplaning. You and others
could be seriously injured.
Hydroplaning occurs when a vehicle
is running at high speeds on a wet
road and a layer of water forms
between the road surface and tires
causing the tires to float on it.
Hydroplaning prevents the driver
from steering correctly and from
slowing down the vehicle with the
brake pedal. Use of Low Aspect Ratio Tires
1. Standard tire
2. Low aspect ratio tire
Low aspect ratio tires for truck
applications (aspect ratio at 70%)
have an air volume 20% to 30%
smaller than that of standard tires.
When air begins to leak, therefore,
low aspect ratio tires adversely
affect vehicle operation much faster
than standard tires. Check air
pressure of low aspect ratio tires
more often than standard tires using
a tire air pressure gauge.
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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)
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Danger (Continued)
.Note that taking off and
mounting tires on wheels
requires proper tools, safety
equipment and special
training. A person can be
severely injured or killed
and damage can result from
using the wrong service
methods. Truck tires and
wheels should be serviced
only by trained people using
the proper equipment.
. Never add air to your tires
unless an accurate pressure
gauge is also used. When
putting air in a tire on the
vehicle, stand to the side
and use a clip-on chuck and
hose extension. In choosing
the right tire pressure, be
careful not to exceed the
maximum pressure
capability shown on the tire;
see the tire pressure charts
in this manual.
(Continued)
Danger (Continued)
.Tire mounting or repair can
result in serious personal
injury or death, if not
performed correctly. This
section has detailed
instructions for proper wheel
and tire replacement, so be
sure to read and follow
them. Truck fleet owners
and operators: You can get
written instructions on truck
tire demounting, repair and
mounting from Rubber
Manufacturers Association
(RMA), 1400 K Street N.W.,
Washington, D.C. 20005,
and also from many tire
stores.
Wheel Nut Torque
{Warning
Never use oil or grease on studs
or nuts. Use the torque specified
for the type of wheels on the (Continued)
Warning (Continued)
vehicle. Snug all wheel nuts and
then tighten to the specified
torque in the numerical sequence
shown. Improperly tightened
wheel nuts could eventually allow
the wheel to come off while the
vehicle is moving, possibly
causing loss of control and
personal injury and property
damage.
When the vehicle, wheel or
fasteners are new, have a
technician tighten wheel stud nuts
and rim clamp nuts with a torque
wrench at 1 040 km (650 mi). This is
necessary because the clamping
system used on the wheels must
seat before the fastener will hold a
uniform clamp load and remain fully
tightened. Also have a technician
tighten wheel stud nuts and rim
clamp nuts with a torque wrench
after installing any wheel.
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In addition, nut tightness on all
wheels should be set with a torque
wrench every 10 400 km (6,500 mi).Tightening torque
500 N·m (362 lb·ft)
Wheel Tightening Sequence
Some studs and nuts have left-hand
threads. Those studs are marked on
their ends with the letter "L".
Install valve stems of dual wheels
180 degrees opposite each other. 1. Finger-tighten the nuts.2. Tighten all nuts to specified torque in order as shown.
Never use oil or grease on the
studs or nuts.
3. If a wheel stud and nut has been replaced, stake the stud
and nut.
{Warning
To help reduce the risk of losing
vehicle control and personal
injury or death, if any stud has
been damaged as a result of a
loose running wheel, all studs for
that wheel should be replaced.
A loose running wheel may cause
only one stud to break but
damage to other studs may not
be noticeable. If stud holes in a
wheel have become elongated or
distorted, replace the wheel.
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Tire Pressure
Tire Load and Inflation Table
Tire Load and Inflation Table
TIRES FOR VEHICLES IN HIGHWAY SERVICE
TIRE LOAD LIMITS AT VARIOUS COLD INFLATION PRESSURES
Tire Size Designation Cold Inflation Pressure (psi) 50 55 60 65 70 75 80 85 90 95
LT215/85R16E Dual Single(lbs) 2470
2680
225/70R19.5F Dual Single(lbs) 3115
33153245
34503415
3640
See Wheels and Tires 0272.
Tire Rotation
{Warning
Be sure to check the wheel studs,
wheel nuts and disc wheel for any
abnormality whenever the disc
wheel is removed.
(Continued)
Warning (Continued)
If you find any abnormal condition
on the wheel studs, wheel nuts or
disc wheel, do not continue to use
the wheel. Contact the nearest
dealer as soon as possible
Tires at different locations wear
differently. For uniform tire wear and
longer tire life, you should rotate the
tires on your vehicle regularly. Make
sure to use tires of the same type on the same axle. If you install tires
of different types on the same axle,
the vehicle may drift right or left
when you apply the brakes.
New tires are more likely to build up
heat and wear faster than old tires,
so they should be installed on the
front axle where the load is smaller.
If there is a difference in diameter
between the inner and outer tires of
a dual-tire wheel, install the smaller
diameter tire inside.
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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
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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.
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{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)