tire size Ram 1500 2015 User Guide

Tire Terminology And Definitions
TermDefinition
B-PillarThe vehicle B-Pillar is the structural member of the body located
behind the front door.
Cold Tire Inflation PressureCold tire inflation pressure is defined as the tire pressure after
the vehicle has not been driven for at least three hours, or driven
less than 1 mile (1.6 km) after sitting for a minimum of three
hours. Inflation pressure is measured in units of PSI (pounds per
square inch) or kPa (kilopascals).
Maximum Inflation PressureThe maximum inflation pressure is the maximum permissible
cold tire inflation pressure for this tire. The maximum inflation
pressure is molded into the sidewall.
Recommended Cold Tire Inflation
Pressure
Vehicle manufacturer’s recommended cold tire inflation pressure
as shown on the tire placard.
Tire PlacardA label permanently attached to the vehicle describing the vehi-
cle’s loading capacity, the original equipment tire sizes and the
recommended cold tire inflation pressures.
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3. Tire size designed for your vehicle.
4. Cold tire inflation pressures for the front, rear, and
spare tires.
Loading
The vehicle maximum load on the tire must not exceed
the load carrying capacity of the tire on your vehicle. You
will not exceed the tire’s load carrying capacity if you
adhere to the loading conditions, tire size, and cold tire
inflation pressures specified on the Tire and Loading
Information placard and in the “Vehicle Loading” section
of this manual.
NOTE:Under a maximum loaded vehicle condition,
gross axle weight ratings (GAWRs) for the front and rear
axles must not be exceeded. For further information on
GAWRs, vehicle loading, and trailer towing, refer to
“Vehicle Loading” in this section.
To determine the maximum loading conditions of your
vehicle, locate the statement “The combined weight of
occupants and cargo should never exceed XXX lbs or
XXX kg” on the Tire and Loading Information placard.
The combined weight of occupants, cargo/luggage and
trailer tongue weight (if applicable) should never exceed
the weight referenced here.
Steps For Determining Correct Load Limit
1. Locate the statement “The combined weight of occu-
pants and cargo should never exceed XXX lbs or
XXX kg” on your vehicle’s placard.
2. Determine the combined weight of the driver and
passengers that will be riding in your vehicle.
3. Subtract the combined weight of the driver and pas-
sengers from XXX lbs or XXX kg.
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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 thana¼ofaninch (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 imme-
diately with another Run Flat tire of identical size and
service description (Load Index and Speed Symbol).
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. 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 informa-
tion, contact an authorized dealer.
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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 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.
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 origi-
nal 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.
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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 equip-
ment 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.
WARNING!
Compact 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.
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Full Size Spare — If Equipped
The full size spare is for temporary emergency use only.
This tire may look like the originally equipped tire on the
front or rear axle of your vehicle, but it is not. This spare
tire may have limited tread life. When the tread is worn
to the tread wear indicators, the temporary use full size
spare tire needs to be replaced. Since it is not the same as
your original equipment tire, replace (or repair) the
original equipment tire and reinstall on the vehicle at the
first opportunity.
Limited-Use Spare — If Equipped
The limited-use spare tire is for temporary emergency
use only. This tire is identified by a label located on the
limited-use spare wheel. This label contains the driving
limitations for this spare. This tire may look like the
original equipped tire on the front or rear axle of your
vehicle, but it is not. Installation of this limited-use spare
tire affects vehicle handling. Since it is not the same as
your original equipment tire, replace (or repair) the
original equipment tire and reinstall on the vehicle at the
first opportunity.
WARNING!
Limited-use spares are for emergency use only. In-
stallation of this limited-use spare tire affects vehicle
handling. With this tire, do not drive more than the
speed listed on the limit-use spare wheel. Keep
inflated to the cold tire inflation pressures listed on
your Tire and Loading Information Placard located
on the driver ’s side B-Pillar or the rear edge of the
driver ’s side door. Replace (or repair) the original
equipment tire at the first opportunity and reinstall it
on your vehicle. Failure to do so could result in loss
of vehicle control.
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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 manu-
facturer strongly recommends that you use tires equiva-
lent to the originals in size, quality and performance
when replacement is needed. Refer to the paragraph on
“Tread Wear Indicator.” 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. See the Tire Sizing Chart ex-
ample found in the Tire Safety Information section of this
manual for more information relating to the Load Index
and Speed Symbol of a tire.
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 your 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
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WARNING!
•Do not use a tire, wheel size or rating other than
that specified for your vehicle. Some combinations
of unapproved tires and wheels may change sus-
pension dimensions and performance characteris-
tics, resulting in changes to steering, handling, and
braking of your vehicle. This can cause unpredict-
able handling and stress to steering and suspen-
sion 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.
(Continued)
WARNING!(Continued)
•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 read-
ings.
SUPPLEMENTAL TIRE PRESSURE INFORMATION —
IF EQUIPPED
A light load vehicle condition is defined as two passen-
gers [150 lbs (68 kg) each] plus 200 lbs (91 kg) of cargo.
Cold tire inflation pressures for a lightly loaded vehicle
will be found on the face of the driver’s door.
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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:
VehicleAxle RecommendationsTire SizesChain Class
1500 ModelsRear OnlyP265/70R17S Class
2500 ModelsRear OnlyLT245/70R17E
LT265/70R18E
LT275/70R18E
U Class
2500 Power Wagon ModelsRear OnlyLT285/70R17DU Class
3500 (Single Rear Wheel)
Models
Rear OnlyLT265/70R18E
LT275/70R18E
U Class
3500 (Dual Rear Wheel)
Models
Front/RearLT235/80R17EU 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 about½mile (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.
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