
378SERVICING AND MAINTENANCE
Check tire pressures more often if subject to a wide range
of outdoor temperatures, as tire pressures vary with
temperature changes.
Tire pressures change by approximately 1 psi (7 kPa) per
12°F (7°C) of air temperature change. Keep this in mind
when checking tire pressure inside a garage, especially in
the Winter.
Example: If garage temperature = 68°F (20°C) and the
outside temperature = 32°F (0°C) then the cold tire
inflation pressure should be increased by 3 psi (21 kPa),
which equals 1 psi (7 kPa) for every 12°F (7°C) for this
outside temperature condition.
Tire pressure may increase from 2 to 6 psi (13 to 40 kPa)
during operation. DO NOT reduce this normal pressure
build up or your tire pressure will be too low.
Tire Pressures For High Speed Operation
The manufacturer advocates driving at safe speeds and
within posted speed limits. Where speed limits or
conditions are such that the vehicle can be driven at high
speeds, maintaining correct tire inflation pressure is very
important. Increased tire pressure and reduced vehicle
loading may be required for high-speed vehicle operation.
Refer to an authorized tire dealer or original equipment
vehicle dealer for recommended safe operating speeds,
loading and cold tire inflation pressures.
Radial Ply Tires
Tire Repair
If your tire becomes damaged, it may be repaired if it
meets the following criteria:
The tire has not been driven on when flat
The damage is only on the tread section of your tire
(sidewall damage is not repairable)
The puncture is no greater than ¼ of an inch (6 mm)
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
immediately with another Run Flat tire of identical size and
service description (Load Index and Speed Symbol).
Replace the tire pressure sensor as well as it is not
designed to be reused.
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
immediately. A Run Flat tire is not repairable. When a Run
Flat tire is changed after being driven in a Run Flat mode
14 psi (96 kPa) condition, please replace the TPMS sensor
as it is not designed to be reused.
NOTE:The TPMS Sensor must be replaced after driving the
vehicle on a flat tire condition.
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.
For more information
Úpage 277.
WARNING!
High speed driving with your vehicle under maximum
load is dangerous. The added strain on your tires could
cause them to fail. You could have a serious collision.
Do not drive a vehicle loaded to the maximum capacity
at continuous speeds above 75 mph (120 km/h).
WARNING!
Combining radial ply tires with other types of tires on
your vehicle will cause your vehicle to handle poorly.
The instability could cause a collision. Always use radial
ply tires in sets of four. Never combine them with other
types of tires.
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SERVICING AND MAINTENANCE379
Tire Spinning
When stuck in mud, sand, snow, or ice conditions, do not
spin your vehicle's wheels above 30 mph (48 km/h) or for
longer than 30 seconds continuously without stopping.
For further information
Úpage 329.
Tread Wear Indicators
Tread wear indicators are in the original equipment tires to
help you in determining when your tires should be
replaced.
Tire Tread
These indicators are molded into the bottom of the tread
grooves. They will appear as bands when the tread depth
becomes 1/16 of an inch (1.6 mm). When the tread is
worn to the tread wear indicators, the tire should be
replaced.
For further information
Úpage 380.
Life Of Tire
The service life of a tire is dependent upon varying factors
including, but not limited to:
Driving style
Tire pressure - Improper cold tire inflation pressures
can cause uneven wear patterns to develop across the
tire tread. These abnormal wear patterns will reduce
tread life, resulting in the need for earlier tire
replacement
Distance driven
Performance tires, tires with a speed rating of V or
higher, and Summer tires typically have a reduced
tread life. Rotation of these tires per the vehicle
scheduled maintenance is highly recommended
NOTE:Wheel Valve Stem must be replaced as well when
installing new tires due to wear and tear in existing tires.
Keep dismounted tires in a cool, dry place with as little
exposure to light as possible. Protect tires from contact
with oil, grease, and gasoline.
WARNING!
Fast spinning tires can be dangerous. Forces generated
by excessive wheel speeds may cause tire damage or
failure. A tire could explode and injure someone.
Do not spin your vehicle's wheels faster than 30 mph
(48 km/h) for more than 30 seconds continuously
when you are stuck, and do not let anyone near a
spinning wheel, no matter what the speed.
1 — Tread Wear Indicators
WARNING!
Tires and the spare tire should be replaced after six
years, regardless of the remaining tread. Failure to
follow this warning can result in sudden tire failure.
You could lose control and have a collision resulting in
serious injury or death.
8
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380SERVICING AND MAINTENANCE
Replacement Tires
The tires on your new vehicle provide a balance of many
characteristics. They should be inspected regularly for
wear and correct cold tire inflation pressures. The
manufacturer strongly recommends using tires equivalent
to the originals in size, quality and performance when
replacement is needed
Úpage 379. Refer to the Tire And
Loading Information Placard or the Vehicle Certification
Label for the size designation of your tire. The Load Index
and Speed Symbol for your tire will be found on the original
equipment tire sidewall.
For more information relating to the Load Index and Speed
Symbol of a tire
Úpage 371.
It is recommended to replace the two front tires or two rear
tires as a pair. Replacing just one tire can seriously affect
your vehicle’s handling. If you ever replace a wheel, make
sure that the wheel’s specifications match those of the
original wheels.
It is recommended you contact an authorized tire dealer or
original equipment dealer with any questions you may
have on tire specifications or capability. Failure to use
equivalent replacement tires may adversely affect the
safety, handling, and ride of your vehicle.
TIRE TYPES
All Season Tires — If Equipped
All Season tires provide traction for all seasons (Spring,
Summer, Autumn, and Winter). Traction levels may vary
between 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. Install Winter tires on your vehicle when
ambient temperatures are less than 40°F (5°C) or if
roads are covered with ice or snow. For more information,
contact an authorized 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.
WARNING!
Do not use a tire, wheel size, load rating, or speed
rating other than that specified for your vehicle.
Some combinations of unapproved tires and wheels
may change suspension dimensions and perfor -
mance characteristics, resulting in changes to
steering, handling, and braking of your vehicle. This
can cause unpredictable handling and stress to
steering and suspension components. You could
lose control and have a collision resulting in serious
injury or death. Use only the tire and wheel sizes with
load ratings approved for your vehicle.
Never use a tire with a smaller load index or capacity,
other than what was originally equipped on your
vehicle. Using a tire with a smaller load index could
result in tire overloading and failure. You could lose
control and have a collision.
Failure to equip your vehicle with tires having
adequate speed capability can result in sudden tire
failure and loss of vehicle control.
CAUTION!
Replacing original tires with tires of a different size may
result in false speedometer and odometer readings.WARNING!
Do not use Summer tires in snow/ice conditions. You
could lose vehicle control, resulting in severe injury or
death. Driving too fast for conditions also creates the
possibility of loss of vehicle control.
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SERVICING AND MAINTENANCE381
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.
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 prohibit
studded tires; therefore, local laws should be checked
before using these tire types.
SPARE TIRES — IF EQUIPPED
NOTE:For vehicles equipped with Tire Service Kit instead of a
spare tire, please refer to “Tire Service Kit” in “In Case Of
Emergency” for further information.
For restrictions when towing with a spare tire designated
for temporary emergency use
Úpage 179.
Spare Tire Matching Original Equipped Tire
And Wheel — If Equipped
Your vehicle may be equipped with a spare tire and wheel
equivalent in look and function to the original equipment
tire and wheel found on the front or rear axle of your
vehicle. This spare tire may be used in the tire rotation for
your vehicle. If your vehicle has this option, refer to an
authorized tire dealer for the recommended tire rotation
pattern.
Compact Spare Tire — If Equipped
The compact spare is for temporary emergency use only.
You can identify if your vehicle is equipped with a compact
spare by looking at the spare tire description on the Tire
And Loading Information Placard located on the driver’s
side door opening or on the sidewall of the tire. Compact
spare tire descriptions begin with the letter “T” or “S”
preceding the size designation. Example: T145/80D18
103M.
T, S = Temporary Spare Tire
Since this tire has limited tread life, the original equipment
tire should be repaired (or replaced) and reinstalled on
your vehicle at the first opportunity.
Do not install a wheel cover or attempt to mount a
conventional tire on the compact spare wheel, since the
wheel is designed specifically for the compact spare tire.
Do not install more than one compact spare tire and wheel
on the vehicle at any given time.
CAUTION!
Because of the reduced ground clearance, do not take
your vehicle through an automatic car wash with a
compact or limited use temporary spare installed.
Damage to the vehicle may result.
WARNING!
Compact and collapsible spares are for temporary
emergency use only. With these spares, do not drive
more than 50 mph (80 km/h). Temporary use spares have limited tread life. When the tread is worn to the
tread wear indicators, the temporary use spare tire
needs to be replaced. Be sure to follow the warnings,
which apply to your spare. Failure to do so could result
in spare tire failure and loss of vehicle control.8
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SERVICING AND MAINTENANCE385
4x4 (4WD)
Trim Level Axle
Tire/Wheel Size Snow Traction Device
(Maximum Projection Beyond Tire Profile Or Equivalent)
Tradesman
Bighorn Lonestar Laramie Rear
275/65R18
275/55R20 S Class
Longhorn Sport
Limited Rear
275/55R20 S Class
REBEL Not Chainable
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.
8
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386SERVICING AND MAINTENANCE
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 all season type
tires. Rotation will increase tread life, help to maintain
mud, snow and wet traction levels and contribute to a
smooth, quiet ride.
For the proper maintenance intervals
Úpage 334. More
frequent rotation is permissible if desired. The reasons for
any rapid or unusual wear should be corrected prior to
rotation being performed.
The suggested rotation method is the “rearward cross”
shown in the following diagram. This rotation pattern does
not apply to some directional tires that must not be
reversed.
Tire Rotation (Rearward Cross)
DEPARTMENT OF TRANSPORTATION
UNIFORM TIRE QUALITY GRADES
The following tire grading categories
were established by the National
Highway Traffic Safety Administration.
The specific grade rating assigned by the
tire's manufacturer in each category is
shown on the sidewall of the tires on
your vehicle.
All passenger vehicle tires must conform
to Federal safety requirements in
addition to these grades.
TREADWEAR
The Treadwear grade is a comparative
rating, based on the wear rate of the tire
when tested under controlled conditions
on a specified government test course.
For example, a tire graded 150 would
wear one and one-half times as well on
the government course as a tire
graded 100.
CAUTION!
To avoid damage to your vehicle or tires, observe the
following precautions:
Because of restricted traction device clearance
between tires and other suspension components, it is
important that only traction devices in good condition
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.
Install device as tightly as possible and then retighten
after driving about ½ mile (0.8 km). Autosock traction
devices do not require retightening.
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 pavement.
Observe the traction device manufacturer’s instruc -
tions on the method of installation, operating speed,
and conditions for use. Always use the suggested oper -
ating speed of the device manufacturer’s if it is less
than 30 mph (48 km/h).
Do not use traction devices on a compact spare tire.
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SERVICING AND MAINTENANCE387
The relative performance of tires
depends upon the actual conditions of
their use, however, and may depart
significantly from the norm due to
variations in driving habits, service
practices, and differences in road
characteristics and climate.
TRACTION GRADES
The Traction grades, from highest to
lowest, are AA, A, B, and C. These grades
represent the tire's ability to stop on wet
pavement, as measured under
controlled conditions on specified
government test surfaces of asphalt and
concrete. A tire marked C may have poor
traction performance.
TEMPERATURE GRADES
The Temperature grades are A (the
highest), B, and C, representing the tire's
resistance to the generation of heat and
its ability to dissipate heat, when tested
under controlled conditions on a
specified indoor laboratory test wheel.
Sustained high temperature can cause
the material of the tire to degenerate
and reduce tire life, and excessive
temperature can lead to sudden tire
failure. The grade C corresponds to a
level of performance, which all
passenger vehicle tires must meet
under the Federal Motor Vehicle Safety
Standard No. 109. Grades B and A
represent higher levels of performance
on the laboratory test wheel, than the
minimum required by law.
STORING THE VEHICLE
If you are storing your vehicle for more than three weeks,
we recommend that you take the following steps to
minimize the drain on your vehicle's battery:
Disconnect the negative cable from battery.
Any time you store your vehicle or keep it out of service
(i.e., vacation) for two weeks or more, run the air condi -
tioning system at idle for about five minutes in the
fresh air and high blower setting. This will ensure
adequate system lubrication to minimize the
possibility of compressor damage when the system
is started again.
WARNING!
The traction grade assigned to this tire is based on
straight-ahead braking traction tests, and does not
include acceleration, cornering, hydroplaning, or peak
traction characteristics.
WARNING!
The temperature grade for this tire is established for a
tire that is properly inflated and not overloaded.
Excessive speed, underinflation, or excessive loading,
either separately or in combination, can cause heat
buildup and possible tire failure.
8
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403
INDEX
AAccessory Drive Belt Inspection .................................. 346
Adaptive Cruise Control (ACC)
(Cruise Control) ................................................... 143
, 145
Adding Engine Coolant (Antifreeze) ............................ 350
Adding Fuel................................................................... 171
Additives, Fuel .............................................................. 393
Adjust Down...........................................................................32
Forward ...................................................................... 32
Rearward ....................................................................32
Up................................................................................ 32
Adjustable Pedals ...........................................................38
Advance Phone Connectivity ....................................... 235
Air Bag Air Bag Operation.................................................... 290
Air Bag Warning Light .................................... 288
, 291
Enhanced Accident Response ...................... 297, 332
Event Data Recorder (EDR).................................... 332 Front Air Bag ........................................................... 291
If Deployment Occurs ............................................. 297
Knee Impact Bolsters ............................................. 294
Maintaining Your Air Bag System .......................... 298
Maintenance ........................................................... 298
Redundant Air Bag Warning Light ......................... 289
Transporting Pets.................................................... 311
Air Bag Light ...............................................108
, 288, 311
Air Cleaner, Engine (Engine Air Cleaner Filter) ........... 342
Air Conditioner Maintenance ...................................... 344
Air Conditioner Refrigerant .......................................... 344
Air Conditioner System ................................................ 344 Air Conditioning........................................................ 54
, 56
Air Conditioning Filter ............................................59, 344
Air Conditioning System ................................................. 59
Air Conditioning, Operating Tips .................................... 59
Air Filter ............................................................... 342
, 344
Air Pressure Tires.......................................................................... 377
Air Suspension .................................................... 134
, 137
Alarm Panic........................................................................... 17
Security Alarm...................................................23
, 110
Alterations/Modifications Vehicle........................................................................ 11
Antifreeze (Engine Coolant) ............................... 350
, 395
Disposal ...................................................................351
Anti-Lock Brake System (ABS) ..................................... 262
Anti-Lock Warning Light................................................ 110
Assist, Hill Start ............................................................. 266
Audio Settings ............................................................... 224
Audio Systems (Radio) ................................................. 191
Auto Down Power Windows............................................ 70
Automatic Door Locks .................................................... 27 Automatic Headlights ..................................................... 48Automatic High Beams ................................................... 47
Automatic Tailgate Release ........................................... 75
Automatic Temperature Control (ATC) .......................... 59
Automatic Transmission ..................................... 125
, 353
Adding Fluid ............................................................. 353
Fluid And Filter Change ...........................................353
Fluid Change ............................................................353 Fluid Level Check ....................................................353 Fluid Type .......................................................353
, 397
Special Additives ..................................................... 353
Automatic Transmission Limp Home Mode ............... 128
AutoPark ....................................................................... 119
AUX Camera .................................................................. 168
Auxiliary Driving Systems ............................................. 269
Axle Fluid.............................................................. 353
, 397
Axle Locker System ...................................................... 140
Axle Lubrication ............................................................ 353
BBack-Up Camera........................................................... 163
Battery..................................................................108, 340
Charging System Light ............................................ 108
Keyless Key Fob Replacement................................. 17
Battery Saver Feature .................................................... 50
Bed Divider ..................................................................... 84 Bed Extender .................................................................. 84
Bed Step ......................................................................... 78
Bedliner......................................................................... 389
Belts, Seat..................................................................... 311
Blind Spot Monitoring .................................................. 269
Bluetooth Connecting To A Particular Mobile Phone Or Audio Device After Pairing ................................. 231
Body Builders Guide..........................................................9
Body Mechanism Lubrication ...................................... 347
Bodywork ...................................................................... 388
B-Pillar Location ........................................................... 374
Brake Assist System..................................................... 263
Brake Control System .................................................. 263
11
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