maintenance RAM 1500 2021 Manual Online

SERVICING AND MAINTENANCE451
cold tire inflation pressure must not exceed the
maximum inflation 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.
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 an
authorized tire dealer or original equipment
vehicle dealer for recommended safe operating
speeds, loading and cold tire inflation
pressures.
Radial Ply 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 than a ¼ of an
inch (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 immediately with another Run Flat tire
of identical size and service description (Load
Index and Speed Symbol). Replace the tire
pressure sensor as well as it is not designed to
be reused.
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
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).
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.
8

21_DT_OM_EN_USC_t.book Page 451

452SERVICING AND MAINTENANCE
limited driving capabilities and needs to be
replaced immediately. A Run Flat tire is not
repairable. When a Run Flat tire is changed
after driving with underinflated tire condition,
please replace the TPM sensor as it is not
designed to be reused when driven under Run
Flat mode 14 psi (96 kPa) condition.
NOTE:
TPM Sensor must be replaced after driving the
vehicle on a flat tire condition.
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.
For more information Úpage 327.
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.
For further information Ú page 391.
Tread Wear Indicators
Tread wear indicators are in the original
equipment tires to help you in determining
when your tires should be replaced.

Tire Tread
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.
For further information Ú
page 453.
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 scheduled maintenance is
highly recommended
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.
1 — Worn Tire
2 — New Tire

21_DT_OM_EN_USC_t.book Page 452

SERVICING AND MAINTENANCE453
(Continued)
NOTE:
Wheel Valve Stem must be replaced as well
when installing new tires due to wear and tear
in existing tires.
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. FCA strongly
recommends that you use tires equivalent to
the originals in size, quality and performance
when replacement is needed Ú page 452. 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.
For more information relating to the Load Index
and Speed Symbol of a tire Ú
page 444.
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!
Tires and the spare tire should be replaced after
six years, regardless of the remaining tread.
Failure to follow this warning can result in sud -
den tire failure. You could lose control and have
a collision resulting in serious injury or death.
WARNING!
Do not use a tire, wheel size, load rating, or
speed rating other than that specified for
your vehicle. Some combinations of unap -
proved tires and wheels may change
suspension dimensions and performance
characteristics, resulting in changes to
steering, handling, and braking of your
vehicle. This can cause unpredictable
handling and stress to steering 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.
8

21_DT_OM_EN_USC_t.book Page 453

454SERVICING AND MAINTENANCE
TIRE TYPES
All Season Tires — If Equipped
All Season tires provide traction for all seasons
(Spring, Summer, Autumn, and Winter). Traction
levels may vary between 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 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.
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; 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
studded tires; therefore, local laws should be
checked before using these tire types.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 readings.
WARNING! (Continued)
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.

21_DT_OM_EN_USC_t.book Page 454

SERVICING AND MAINTENANCE455
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.
For restrictions when towing with a spare tire
designated for temporary emergency use
Úpage 222.
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
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.
Collapsible Spare Tire — If Equipped
The collapsible spare is for temporary
emergency use only. You can identify if your
vehicle 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.
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.
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 control.
8

21_DT_OM_EN_USC_t.book Page 455

456SERVICING AND MAINTENANCE
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.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.
WHEEL AND WHEEL TRIM CARE
All wheels and wheel trim, especially aluminum
and chrome plated wheels, should be cleaned
regularly using mild (neutral Ph) soap and water
to maintain their luster and to prevent
corrosion. Wash wheels with the same soap
solution recommended for the body of the
vehicle and remember to always wash when the
surfaces are not hot to the touch.
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 control.
WARNING!
Limited use spares are for emergency use
only. Installation of this limited use spare tire
affects vehicle handling. With this tire, do not
drive more than the speed listed on the
limited 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.

21_DT_OM_EN_USC_t.book Page 456

SERVICING AND MAINTENANCE457
Your wheels are susceptible to deterioration
caused by salt, sodium chloride, magnesium
chloride, calcium chloride, etc., and other road
chemicals used to melt ice or control dust on
dirt roads. Use a soft cloth or sponge and mild
soap to wipe away promptly. Do not use harsh
chemicals or a stiff brush. They can damage the
wheel’s protective coating that helps keep them
from corroding and tarnishing. When cleaning extremely dirty wheels including
excessive brake dust, care must be taken in the
selection of tire and wheel cleaning chemicals
and equipment to prevent damage to the
wheels. Mopar Wheel Treatment or Mopar
Chrome Cleaner or their equivalent is
recommended or select a non-abrasive,
non-acidic cleaner for aluminum or chrome
wheels.NOTE:
If you intend parking or storing your vehicle for
an extended period after cleaning the wheels
with wheel cleaner, drive your vehicle and apply
the brakes to remove the water droplets from
the brake components. This activity will remove
the red rust on the brake rotors and prevent
vehicle vibration when braking.
Dark Vapor Chrome, Black Satin Chrome, or
Low Gloss Clear Coat Wheels
CAUTION!
Avoid products or automatic car washes that
use acidic solutions or strong alkaline
additives or harsh brushes. Many aftermarket
wheel cleaners and automatic car washes
may damage the wheel's protective finish.
Such damage is not covered by the New
Vehicle Limited Warranty. Only car wash soap,
Mopar Wheel Cleaner or equivalent is
recommended.
CAUTION!
Do not use scouring pads, steel wool, a bristle
brush, metal polishes or oven cleaner. These
products may damage the wheel's protective
finish. Such damage is not covered by the
New Vehicle Limited Warranty. Only car wash
soap, Mopar Wheel Cleaner or equivalent is
recommended.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
USING MILD SOAP AND WATER WITH A SOFT
CLOTH. Used on a regular basis; this is all that
is required to maintain this finish.
8

21_DT_OM_EN_USC_t.book Page 457

458SERVICING AND MAINTENANCE
SNOW TRACTION DEVICES
Use of traction devices require sufficient
tire-to-body clearance. Due to limited clearance,
the following snow traction devices are
recommended. Follow these recommendations
to guard against damage:
Snow traction device must be of proper size
for the tire, as recommended by the snow
traction device manufacturer.
No other tire sizes are recommended for use
with the snow traction device.
Please follow the table below for the recom -
mended tire size, axle and snow traction
device:
4x2 (2WD)
Trim Level Axle
Tire/Wheel Size Snow Traction Device
(maximum projection beyond tire profile or equivalent)
HFE
Tradesman
Bighorn Lonestar Laramie Rear
275/65R18
275/55R20 S Class
Longhorn Sport
Limited Rear
275/55R20 S Class
REBEL Not Chainable

21_DT_OM_EN_USC_t.book Page 458

SERVICING AND MAINTENANCE459
(Continued)
(Continued)
4x4 (4WD)
Trim Level Axle
Tire/Wheel Size Snow Traction Device
(maximum projection beyond tire profile or equivalent)
Tradesman
Bighorn Lonestar Laramie Rear
275/65R18
275/55/R20 S Class
Longhorn Sport
Limited Rear
275/55R20 S Class
REBEL Not Chainable
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 clear-
ance between tires and other suspension
components, it is important that only trac-
tion devices in good condition 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 retighten after driving about ½ mile
(0.8 km). Autosock traction devices do not
require retightening.
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
pavement.
CAUTION! (Continued)
8

21_DT_OM_EN_USC_t.book Page 459

460SERVICING AND MAINTENANCE
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 aggressive 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.
For the proper maintenance intervals
Úpage 395. More frequent rotation is
permissible if desired. The reasons for any rapid or unusual wear should be corrected prior to
rotation being performed.
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.

Tire Rotation (Rearward Cross)

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 manufacturer 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
characteristics and climate.
Observe the traction device manufacturer’s
instructions 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.
CAUTION!
(Continued)

21_DT_OM_EN_USC_t.book Page 460