inflation pressure Ram 1500 2015 User Guide

Tire Inflation Pressures
The proper cold tire inflation pressure is listed on the
driver’s side B-Pillar or rear edge of the driver’s side
door.
At least once a month:
•Check and adjust tire pressure with a good quality
pocket-type pressure gauge. Do not make a visual judge-
ment 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 sitting for a minimum of three hours.
The cold tire inflation pressure must not exceed the
maximum inflation pressure molded into the tire side-
wall.
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
610 STARTING AND OPERATING

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 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 dealer or original
equipment vehicle dealer for recommended safe operat-
ing 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.
5
STARTING AND OPERATING 611

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.
5
STARTING AND OPERATING 613

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.
Spare Tires — If Equipped
NOTE:For vehicles equipped with Tire Service Kit
instead of a spare tire, please refer to “Tire Service Kit” in
“What To Do In Emergencies” for further information.
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.
614 STARTING AND OPERATING

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.
616 STARTING AND OPERATING

These indicators are molded into the bottom of the tread
grooves. They will appear as bands when the tread depth
becomes a 1/16 of an inch (2 mm). When the tread is
worn to the tread wear indicators, the tire should be
replaced. Refer to “Replacement Tires” in this section for
further information.
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 replace-
ment.
•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 main-
tenance schedule is highly recommended.
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.
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.
618 STARTING AND OPERATING

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
the safety, handling, and ride of your vehicle.5
STARTING AND OPERATING 619

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.
620 STARTING AND OPERATING

CAUTION!(Continued)
•When replacing a flat, the spare tire may have to be
remounted on the rim, or installed at a different
location, to maintain the correct placement of the
tire on the wheel relative to the tire/wheel position
on the truck. For example, if the spare is used to
replace an outer rear tire it will have to be re-
mounted on the rim so that the wheel is dished
inward. That way the tread design of asymmetrical
tires and the white writing of the OWL tires will
maintain proper position.
TIRE PRESSURE MONITOR SYSTEM (TPMS)
The Tire Pressure Monitor System (TPMS) will warn the
driver of a low tire pressure based on the vehicle recom-
mended cold placard pressure.
The tire pressure will vary with temperature by about 1
psi (7 kPa) for every 12°F (6.5°C). This means that when
the outside temperature decreases, the tire pressure will
decrease. Tire pressure should always be set based on
cold inflation tire pressure. This 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 inflation pressure molded into
the tire sidewall. Refer to “Tires – General Information”
in “Starting and Operating” for information on how to
properly inflate the vehicle’s tires. The tire pressure will
also increase as the vehicle is driven - this is normal and
there should be no adjustment for this increased pres-
sure.
The TPMS will warn the driver of a low tire pressure if
the tire pressure falls below the low-pressure warning
limit for any reason, including low temperature effects
and natural pressure loss through the tire.
626 STARTING AND OPERATING

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.”
628 STARTING AND OPERATING