tires Ram 1500 2019 Service Manual

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 impor-
tant. 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.
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).
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. Always use
radial ply tires in sets of four. Never combine them
with other types of 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 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 immedi-
ately with another Run Flat tire of identical size and service
description (Load Index and Speed Symbol).
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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.
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 informa-
tion.
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.
Refer to “Freeing A Stuck Vehicle” in “In Case Of Emer-
gency” for further information.
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.
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SERVICING AND MAINTENANCE 535

Tread Wear Indicators
Tread wear indicators are in the original equipment tires to
help you in determining when your tires should be re-
placed.
These indicators are molded into the bottom of the tread
grooves. They will appear as bands when the tread depthbecomes a 1/16 of an inch (1.6 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 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.
Tire Tread
1—WornTire
2—NewTire 536 SERVICING AND MAINTENANCE

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.
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 equivalent
to the originals in size, quality and performance when
replacement is needed. Refer to the paragraph on “Tread
Wear Indicators” in this section. 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 example 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 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.
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 steer-
ing, handling, and braking of your vehicle. This can
cause unpredictable handling and stress to steering
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WARNING!(Continued)
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 ad-
equate 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.
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 condi-
tions, 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 am-
bient 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.
538 SERVICING AND MAINTENANCE

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. 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 stud-
ded 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.
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.
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
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SERVICING AND MAINTENANCE 539

Dark Vapor Chrome, Black Satin Chrome, or Low Gloss
Clear Coat Wheels
CAUTION!
If your vehicle is equipped with these specialty
wheels, DO NOT USE wheel cleaners, abrasives, or
polishing compounds. They will permanently damage
this finish and such damage is not covered by the New
Vehicle Limited Warranty. HAND WASH ONLY US-
ING MILD SOAP AND WATER WITH A SOFT
CLOTH. Used on a regular basis; this is all that is
required to maintain this finish.
Tire Chains (Traction Devices)
Use of traction devices require sufficient tire-to-body clear-
ance. 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 SizesChain Class
1500 Models Rear Only275/65R18
275/55R20 S Class
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
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CAUTION!(Continued)
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.
• 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 manufacturer ’s if it is
less than 30 mph (48 km/h).
• Do not use traction devices on a compact spare tire.
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 aggres-
sive 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.
Refer to the “Maintenance Plan” for the proper mainte-
nance intervals. More frequent rotation is permissible if
desired. The reasons for any rapid or unusual wear should
be corrected prior to rotation being performed.
544 SERVICING AND MAINTENANCE

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.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 manu-
facturer 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. 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 charac-
teristics and climate.
Tire Rotation
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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 condi-
tions on specified government test surfaces of asphalt
and concrete. A tire marked C may have poor traction
performance.
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.
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 pas-
senger 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.
WARNING!
The temperature grade for this tire is established for
a tire that is properly inflated and not overloaded.
Excessive speed, under-inflation, or excessive load-
ing, either separately or in combination, can cause
heat buildup and possible tire failure.
STORING THE VEHICLE
If you are storing your vehicle for more than 21 days, 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 compres-
sor damage when the system is started again.
546 SERVICING AND MAINTENANCE