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Consult an authorized tire dealer for tire repairs and
additional information.
Damaged Run Flat tires, or Run Flat tires that have
experienced a loss of pressure should be replaced imme-
diately with another Run Flat tire of identical size and
service description (Load Index and Speed Code).
Tire Types
All Season Tires — If Equipped
All Season tires provide traction for all seasons (spring,
summer, fall and winter). Traction levels may vary be-
tween different all season tires. All season tires can be
identified by the M+S, M&S, M/S or MS designation on
the tire sidewall. Use all season tires only in sets of four;
failure to do so may adversely affect the safety and
handling of your vehicle.
Summer Or Three Season Tires — If Equipped
Summer tires provide traction in both wet and dry
conditions, and are not intended to be driven in snow or
on ice. If your vehicle is equipped with summer tires, be
aware these tires are not designed for winter or cold
driving conditions. For more information, contact a au-
thorized dealer. Summer tires do not contain the all
season designation or mountain/snowflake symbol on
the tire sidewall.
Use summer tires only in sets of four; failure to do so may
adversely affect the safety and handling of your vehicle.
Snow Tires
Some areas of the country require the use of snow tires
during the winter. Snow tires can be identified by a
mountain/snowflake symbol on the tire sidewall.
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If you need snow tires, select tires equivalent in size and
type to the original equipment tires. Use snow tires only
in sets of four; failure to do so may adversely affect the
safety and handling of your vehicle.
Snow tires generally have lower speed ratings than what
was originally equipped with your vehicle and should
not be operated at sustained speeds over 75 mph
(120 km/h). For speeds above 75 mph (120 km/h) refer to
original equipment or an authorized tire dealer for
recommended safe operating speeds, loading and cold
tire inflation pressures.
While studded tires improve performance on ice, skid
and traction capability on wet or dry surfaces may be
poorer than that of non-studded tires. Some states pro-
hibit studded tires; therefore, local laws should be
checked before using these tire types.Run Flat Tires — If Equipped
Run Flat tires allow you the capability to drive 50 miles
(80 km) at 50 mph (80 km/h) after a rapid loss of inflation
pressure. This rapid loss of inflation is referred to as the
Run Flat mode. A Run Flat mode occurs when the tire
inflation pressure is of/or below 14 psi (96 kPa). Once a
Run Flat tire reaches the run flat mode it has limited
driving capabilities and needs to be replaced immedi-
ately. A Run Flat tire is not repairable.
It is not recommended driving a vehicle loaded at full
capacity or to tow a trailer while a tire is in the run flat
mode.
See the tire pressure monitoring section for more infor-
mation.
5
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TIRE CHAINS (TRACTION DEVICES)
Use of traction devices require sufficient tire-to-body
clearance. Follow these recommendations to guard
against damage.
•Traction device must be of proper size for the tire, as
recommended by the traction device manufacturer.
Please follow the table below for proper tire size, chain
type, and axle recommendations:
Vehicle Axle Recommendations Tire Sizes Chain Class
Chassis Cab 3500
(Single Rear Wheel) Models Rear Only
LT265/70R18E U Class
Chassis Cab 3500
(Dual Rear Wheel) 4X2 Models Rear Only
LT235/80R17E U Class
Chassis Cab 3500
(Dual Rear Wheel) 4X4 Models Front/Rear
LT235/80R17E U Class
Chassis Cab 4500/5500 Models Rear Only225/70R19.5G U Class
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WARNING!
Using tires of different size and type (M+S, Snow)
between front and rear axles can cause unpredictable
handling. You could lose control and have a collision.
CAUTION!
To avoid damage to your vehicle or tires, observe the
following precautions:
•Because of restricted traction device clearance be-
tween tires and other suspension components, it is
important that only traction devices in good condi-
tion are used. Broken devices can cause serious
damage. Stop the vehicle immediately if noise
occurs that could indicate device breakage. Remove
the damaged parts of the device before further use.
(Continued)
CAUTION! (Continued)
•Install device as tightly as possible and then re-
tighten after driving about ½ mile (0.8 km).
• Do not exceed 30 mph (48 km/h).
• Drive cautiously and avoid severe turns and large
bumps, especially with a loaded vehicle.
• Do not drive for a prolonged period on dry pave-
ment.
• Observe the traction device manufacturer ’s instruc-
tions on the method of installation, operating
speed, and conditions for use. Always use the
suggested operating speed of the device manufac-
turer ’s if it is less than 30 mph (48 km/h).
• Do not use traction devices on a compact spare tire.
5
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TIRE ROTATION RECOMMENDATIONS
Tires on the front and rear axles of vehicles operate at
different loads and perform different steering, driving,
and braking functions. For these reasons, they wear at
unequal rates.
These effects can be reduced by timely rotation of tires.
The benefits of rotation are especially worthwhile with
aggressive tread designs such as those on On/Off Road
type tires. Rotation will increase tread life, help to main-
tain mud, snow, and wet traction levels, and contribute to
a smooth, quiet ride.
Refer to the “Maintenance Schedule” for the proper
maintenance intervals. More frequent rotation is permis-
sible if desired. The reasons for any rapid or unusual
wear should be corrected prior to rotation being per-
formed.NOTE:
On Canadian vehicles only, if your vehicle is
equipped with All-Season type tires on the front and
On/Off Road type tires mounted on the rear, do not use
a front to back rotation pattern. Instead, rotate your tires
side to side at the recommended intervals.
Tire Rotation
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CAUTION!
•The TPMS has been optimized for the original
equipment tires and wheels. TPMS pressures and
warning have been established for the tire size
equipped on your vehicle. Undesirable system op-
eration or sensor damage may result when using
replacement equipment that is not of the same size,
type, and/or style. Aftermarket wheels can cause
sensor damage. Using aftermarket tire sealants may
cause the Tire Pressure Monitoring System (TPMS)
sensor to become inoperable. After using an after-
market tire sealant it is recommended that you take
your vehicle to your local dealer to have your
sensor function checked.
• After inspecting or adjusting the tire pressure,
always reinstall the valve stem cap. This will
prevent moisture and dirt from entering the valve
stem, which could damage the TPM sensor. NOTE:
•
The TPMS is not intended to replace normal tire care
and maintenance or to provide warning of a tire failure
or condition.
• The TPMS should not be used as a tire pressure gauge
while adjusting your tire pressure.
• Driving on a significantly under-inflated tire causes
the tire to overheat and can lead to tire failure.
Under-inflation also reduces fuel efficiency and tire
tread life, and may affect the vehicle’s handling and
stopping ability.
• The TPMS is not a substitute for proper tire mainte-
nance, and it is the driver ’s responsibility to maintain
correct tire pressure using an accurate tire pressure
gauge, even if under-inflation has not reached the level
to trigger illumination of the “Tire Pressure Monitor-
ing Telltale Light.”
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Consider the following items when computing the
weight on the rear axle of the vehicle:
•The tongue weight of the trailer
• The weight of any other type of cargo or equipment
put in or on your vehicle
• The weight of the driver and all passengers
NOTE: Remember that everything put into or on the
trailer adds to the load on your vehicle. Also, additional
factory-installed options or dealer-installed options must
be considered as part of the total load on your vehicle.
Refer to “Tire Safety Information/Tire and Loading In-
formation Placard” in “Starting and Operating” for fur-
ther information.Towing Requirements
To promote proper break-in of your new vehicle drive-
train components the following guidelines are recom-
mended:
CAUTION!
• Do not tow a trailer at all during the first 500 miles
(805 km) the new vehicle is driven. The engine, axle
or other parts could be damaged.
• Then, during the first 500 miles (805 km) that a
trailer is towed, do not drive over 50 mph (80 km/h)
and do not make starts at full throttle. This helps
the engine and other parts of the vehicle wear in at
the heavier loads.
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Adjusting GAIN
NOTE:This should only be performed in a traffic free
environment at speeds of approximately 20–25 mph
(30–40 km/h).
1. Make sure the trailer brakes are in good working condition, functioning normally and properly ad-
justed. See your trailer dealer if necessary.
2. Hook up the trailer and make the electrical connec- tions according to the trailer manufacturer’s instruc-
tions.
3. When a trailer with electric/EOH brakes is plugged in, the trailer connected message should appear in the
EVIC (if the connection is not recognized by the ITBM,
braking functions will not be available), the GAIN
setting will illuminate and the correct type of trailer
must be selected from the EVIC options. 4. Press the UP or DOWN button on the steering wheel
until “TRAILER TOW” appears on the screen.
5. Press the RIGHT arrow on the steering wheel to enter “TRAILER TOW”.
6. Press the UP or DOWN buttons until Trailer Brake Type appears on the screen.
7. Press the RIGHT arrow and then press the UP or DOWN buttons until the proper Trailer Brake Type
appears on the screen.
8. In a traffic-free environment, tow the trailer on a dry, level surface at a speed of 20–25 mph (30–40 km/h)
and squeeze the manual brake control lever com-
pletely.
9. If the trailer wheels lockup (indicated by squealing tires), reduce the GAIN setting; if the trailer wheels
turn freely, increase the GAIN setting.
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