2018 Ram 1500 User Guide

• For the following example, the combinedweight of occupants and cargo should never
exceed 865 lbs (392 kg).
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WARNING!
Overloading of your tires is dangerous.
Overloading can cause tire failure, affect
vehicle handling, and increase your stop-
ping distance. Use tires of the recom-
mended 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. Four primary areas are affected by
improper tire pressure:
• Safety and Vehicle Stability
• Economy
• Tread Wear
• Ride ComfortSafety
WARNING!
• Improperly inflated tires are dangerous
and can cause collisions.
• Underinflation increases tire flexing and
can result in overheating and tire failure.
• Overinflation reduces a tire's ability to cushion shock. Objects on the road and
chuckholes can cause damage that re-
sult in tire failure.
• Overinflated or underinflated tires can
affect vehicle handling and can fail sud-
denly, resulting in loss of vehicle con-
trol.
• Unequal tire pressures can cause steer-
ing problems. You could lose control of
your vehicle.
• 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 recommended cold tire inflation
pressure. Both under-inflation and over-inflation affect
the stability of the vehicle and can produce a
feeling of sluggish response or over respon-
siveness in the steering.
NOTE:
• Unequal tire pressures from side to side
may cause erratic and unpredictable steer-
ing response.
• Unequal tire pressure from side to side may cause the vehicle to drift left or right.
Fuel Economy
Underinflated tires will increase tire rolling
resistance resulting in higher fuel consump-
tion.
Tread Wear
Improper cold tire inflation pressures can
cause abnormal wear patterns and reduced
tread life, resulting in the need for earlier tire
replacement.
Ride Comfort And Vehicle Stability
Proper tire inflation contributes to a comfort-
able ride. Over-inflation produces a jarring
and uncomfortable ride.
SERVICING AND MAINTENANCE
264

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 goodquality 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 pres-
sure, always reinstall the valve stem cap.
This will prevent moisture and dirt from
entering the valve stem, which could dam-
age 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 pres-
sure 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.
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 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
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).
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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 repair-
able).
• The puncture is no greater thana¼ofan inch (6 mm).
Consult an authorized tire dealer for tire re-
pairs 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).
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 capabili-
ties 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 information.
Tire Spinning
When stuck in mud, sand, snow, or ice con-
ditions, 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 Emergency” 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 sec-
onds continuously when you are stuck,
and do not let anyone near a spinning
wheel, no matter what the speed.
SERVICING AND MAINTENANCE
266

Tread Wear Indicators
Tread wear indicators are in the original
equipment tires to help you in determining
when your tires should be replaced.
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 (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 inflationpressures can cause uneven wear patterns
to develop across the tire tread. These ab-
normal 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 scheduled mainte-
nance 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.
Replacement Tires
The tires on your new vehicle provide a bal-
ance of many characteristics. They should be
inspected regularly for wear and correct cold
tire inflation pressures. The manufacturer
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 Indi-
cators” 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.
Tire Tread
1 — Worn Tire
2 — New Tire
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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 autho-
rized 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 per-
formance characteristics, resulting in
changes to steering, handling, and brak-
ing of your vehicle. This can cause un-
predictable handling and stress to steer-
ing and suspension components. You
WARNING!
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 origi-
nally equipped on your vehicle. Using a
tire with a smaller load index could re-
sult 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 speedom-
eter and odometer readings.
Tire Types
All Season Tires — If Equipped
All Season tires provide traction for all sea-
sons (Spring, Summer, Fall, and Winter).
Traction levels may vary between different all
season tires. All season tires can be identi-
fied by the M+S, M&S, M/S or MS designa-
tion 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.SERVICING AND MAINTENANCE
268

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 con-
ditions. 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
original equipment
tires. Use snow tires
only in sets of four; fail-ure 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 sus-
tained 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 pres-
sures.
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
For vehicles equipped with Tire Service Kit
instead of a spare tire, please refer to “Tire
Service Kit” in “In Case Of Emergency” in the
Owner’s Manual for further information.
CAUTION!
Because of the reduced ground clearance,
do not take your vehicle through an auto-
matic 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 your vehicle. If your vehicle has this op-
tion, refer to an authorized tire dealer for the
recommended tire rotation pattern.
Compact Spare Tire — If Equipped
The compact spare is for temporary emer-
gency use only. You can identify if your ve-
hicle 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
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sidewall of the tire. Compact spare tire de-
scriptions 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.
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
WARNING!
your spare. Failure to do so could result in
spare tire failure and loss of vehicle con-
trol.
Collapsible Spare Tire — If Equipped
The collapsible spare is for temporary emer-
gency use only. You can identify if your ve-
hicle is equipped with a collapsible 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.
Collapsible spare tire description example:
165/80-17 101P.
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.
Inflate collapsible tire only after the wheel is
properly installed to the vehicle. Inflate the
collapsible tire using the electric air pump
before lowering the vehicle. Do not install a wheel cover or attempt to
mount a conventional tire on the collapsible
spare wheel, since the wheel is designed
specifically for the collapsible spare tire.
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 con-
trol.
Full Size Spare — If Equipped
The full size spare is for temporary emer-
gency 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
SERVICING AND MAINTENANCE
270