tire pressure Ram C/V 2013 User Guide

NOTE:
•P (Passenger) - Metric tire sizing is based on U.S.
design standards. P-Metric tires have the letter “P”
molded into the sidewall preceding the size designa-
tion. Example: P215/65R15 95H.
• European-Metric tire sizing is based on European
design standards. Tires designed to this standard have
the tire size molded into the sidewall beginning with
the section width. The letter Pis absent from this tire
size designation. Example: 215/65R15 96H.
• LT (Light Truck) - Metric tire sizing is based on U.S.
design standards. The size designation for LT-Metric tires is the same as for P-Metric tires except for the
letters “LT” that are molded into the sidewall preced-
ing the size designation. Example: LT235/85R16.
• Temporary spare tires are spares designed for tempo-
rary emergency use only. Temporary high pressure
compact spare tires have the letter “T” or “S” molded
into the sidewall preceding the size designation. Ex-
ample: T145/80D18 103M.
• High flotation tire sizing is based on U.S. design
standards and it begins with the tire diameter molded
into the sidewall. Example: 31x10.5 R15 LT.
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EXAMPLE:
R = Construction code
—R means radial construction
— D means diagonal or bias construction
15 = Rim diameter in inches (in)
Service Description: 95= Load Index
— A numerical code associated with the maximum load a tire can carry
H = Speed Symbol
— A symbol indicating the range of speeds at which a tire can carry a load corresponding to
its load index under certain operating conditions
— The maximum speed corresponding to the speed symbol should only be achieved under
specified operating conditions (i.e., tire pressure, vehicle loading, road conditions, and
posted speed limits)
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EXAMPLE:
Load Identification: ....blank.... = Absence of any text on the sidewall of the tire indicates a Standard Load (SL) tire
Extra Load (XL) = Extra load (or reinforced) tire
Light Load (LL) = Light load tire
C, D, E, F, G = Load range associated with the maximum load a tire can carry at a specified pressure
Maximum Load— Maximum load indicates the maximum load this tire is designed to carry
Maximum Pressure— Maximum pressure indicates the maximum permissible cold tire inflation pressure for
this tire
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Tire Terminology And Definitions
TermDefinition
B-Pillar The vehicle B-Pillar is the structural member of the body located
behind the front door.
Cold Tire Inflation Pressure Cold tire inflation pressure is defined as the tire pressure after
the vehicle has not been driven for at least 3 hours, or driven less
than 1 mile (1.6 km) after sitting for a three hour period. Inflation
pressure is measured in units of PSI (pounds per square inch) or
kPa (kilopascals).
Maximum Inflation Pressure The 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 Pres- sure Vehicle manufacturer’s recommended cold tire inflation pressure
as shown on the tire placard.
Tire Placard A paper label permanently attached to the vehicle describing the
vehicle’s loading capacity, the original equipment tire sizes and
the recommended cold tire inflation pressures.
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Tire Loading And Tire Pressure
Tire And Loading Information Placard Location
NOTE:The proper cold tire inflation pressure is listed on
the driver ’s side B-Pillar or the rear edge of the driver’s
side door.
Tire And Loading Information Placard
Thisplacard tells you important information about the:
1) number of people that can be carried in the vehicle
2) total weight your vehicle can carryB-PillarLocation for Tire And Loading Information
Placard
Tire and Loading Information Placard
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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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WARNING!
Overloading of your tires is dangerous. Overloading
can cause tire failure, affect vehicle handling, and
increase your stopping distance. Use tires of the
recommended load capacity for your vehicle. Never
overload them.
TIRES — GENERAL INFORMATION
Tire Pressure
Proper tire inflation pressure is essential to the safe and
satisfactory operation of your vehicle. Three primary
areas are affected by improper tire pressure:
Safety
WARNING!
•Improperly inflated tires are dangerous and can
cause collisions.
• Under-inflation increases tire flexing and can re-
sult in over-heating and tire failure.
• Over-inflation reduces a tire’s ability to cushion
shock. Objects on the road and chuckholes can
cause damage that result in tire failure.
• Over-inflated or under-inflated tires can affect ve-
hicle handling and can fail suddenly, resulting in
loss of vehicle control.
• Unequal tire pressures can cause steering prob-
lems. You could lose control of your vehicle.
(Continued)
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WARNING!(Continued)
•Unequal tire pressures from one side of the vehicle
to the other can cause the vehicle to drift to the
right or left.
• Always drive with each tire inflated to the recom-
mended cold tire inflation pressure.
Economy
Improper inflation pressures can cause uneven wear
patterns to develop across the tire tread. These abnormal
wear patterns will reduce tread life resulting in a need for
earlier tire replacement. Under-inflation also increases
tire rolling resistance resulting in higher fuel consump-
tion.
Ride Comfort And Vehicle Stability
Proper tire inflation contributes to a comfortable ride.
Over-inflation produces a jarring and uncomfortable
ride. Both under-inflation and over-inflation affect the
stability of the vehicle and can produce a feeling of
sluggish response or over responsiveness in the steering.
Unequal tire pressures from side to side may cause erratic
and unpredictable steering response.
Unequal tire pressure from side to side may cause the
vehicle to drift left or right.
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Tire Inflation Pressures
At least once a month:
•Check and adjust tire pressure with a good quality
pocket-type pressure gauge. Do not make a visual
judgement when determining proper inflation. Tires
may look properly inflated even when they are under-
inflated.
• Inspect tires for signs of tire wear or visible damage.
CAUTION!
After inspecting or adjusting the tire pressure, al-
ways reinstall the valve stem cap. This will prevent
moisture and dirt from entering the valve stem,
which could damage the valve stem.
Inflation pressures specified on the placard are always
“cold tire inflation pressure.” Cold 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 a three hour period. The cold tire
inflation pressure must not exceed the maximum infla-
tion pressure molded into the tire sidewall.
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.
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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 condi-
tions 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 opera-
tion. Refer to your authorized tire or original equipment
vehicle dealer for recommended safe operating speeds,
loading and cold tire inflation pressures.
WARNING!
High speed driving with your vehicle under maxi-
mum 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).
Radial Ply Tires
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. Al-
ways use radial ply tires in sets of four. Never
combine them with other types of tires.
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