maintenance RAM CHASSIS CAB 2023 Manual PDF

SERVICING AND MAINTENANCE393
Tire Terminology And Definitions
Term Definition
B-pillarThe 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 three hours, or driven less than 1 mile (1.6 km)
after sitting for a minimum of three hours. 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 Pressure Vehicle manufacturer's recommended cold tire inflation pressure as shown
on the tire placard.
Tire Placard A 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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394SERVICING AND MAINTENANCE
Tire Loading And Tire Pressure
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.
Check the inflation pressure of each tire, including
the spare tire (if equipped), at least monthly and
inflate to the recommended pressure for your
vehicle.

Example Tire Placard Location (Door) Example Tire Placard Location (B-pillar)

Tire And Loading Information Placard

Tire And Loading Information Placard
This placard tells you important information about
the:

1. Number of people that can be carried in the
vehicle.

2. Total weight your vehicle can carry.
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
Úpage 180.
NOTE:Under a maximum loaded vehicle condition, gross
axle weight ratings (GAWR) for the front and rear
axles must not be exceeded.
For further information on GAWR, vehicle loading,
and trailer towing Ú page 180.

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SERVICING AND MAINTENANCE395
To determine the maximum loading conditions of
your vehicle, locate the statement “The combined
weight of occupants and cargo should never
exceed XXX kg or XXX lbs” 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 occupants and cargo should
never exceed XXX kg or XXX lbs.” 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 passengers from XXX kg or
XXX lbs. (4) The resulting figure equals the
available amount of cargo and luggage
load capacity. For example, if “XXX”
amount equals 1400 lbs. and there will
be five 150 lb passengers in your
vehicle, the amount of available cargo
and luggage load capacity is 650 lbs.
(1400-750 (5x150) = 650 lbs.)
(5) Determine the combined weight of
luggage and cargo being loaded on the
vehicle. That weight may not safely
exceed the available cargo and luggage
load capacity calculated in Step 4.
(6) If your vehicle will be towing a trailer,
load from your trailer will be transferred
to your vehicle. Consult this manual to
determine how this reduces the
available cargo and luggage load
capacity of your vehicle.
Metric Example For Load Limit
For example, if “XXX” amount equals 635 kg and
there will be five 68 kg passengers in your vehicle,
the amount of available cargo and luggage load
capacity is 295 kg (635-340 (5x68) = 295 kg) as
shown in step 4.
NOTE:
If your vehicle will be towing a trailer, load from
your trailer will be transferred to your vehicle.
The following table shows examples on how to
calculate total load, cargo/luggage, and towing
capacities of your vehicle with varying seating
configurations and number and size of occu
-
pants. This table is for illustration purposes only
and may not be accurate for the seating and
load carry capacity of your vehicle.
For the following example, the combined weight
of occupants and cargo should never exceed
865 lbs (392 kg).
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SERVICING AND MAINTENANCE397
(Continued)
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
Fuel Economy
Tread Wear
Ride Comfort and Vehicle Stability
Safety Both underinflation and overinflation affect the
stability of the vehicle and can produce a feeling of
sluggish response or over responsiveness in the
steering.
NOTE:
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.Fuel Economy
Underinflated tires will increase tire rolling
resistance resulting in higher fuel consumption.
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 comfortable
ride. Overinflation produces a jarring and
uncomfortable ride.
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 judgment when determining
proper inflation. Tires may look properly inflated
even when they are underinflated.
Inspect tires for signs of tire wear or visible
damage.
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.
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 result in tire failure.
Overinflated or underinflated tires can affect
vehicle handling and can fail suddenly,
resulting in loss of vehicle control.
Unequal tire pressures can cause steering
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.
WARNING!
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398SERVICING AND MAINTENANCE
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
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 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.
CAUTION!
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 valve stem.
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.

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SERVICING AND MAINTENANCE399
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. When a Run Flat
tire is changed after being driven under a Run Flat
mode 14 psi (96 kPa) condition, please replace the
TPMS sensor as it is not designed to be reused.
NOTE:TPMS 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.
See the Tire Pressure Monitoring System section
for more information.
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.
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 1/16 of an inch (1.6 mm).
When the tread is worn to the tread wear
indicators, the tire should be replaced.
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 pres
-
sures 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.
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 — Tread Wear Indicators
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.
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400SERVICING AND MAINTENANCE
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. The manufacturer strongly
recommends that you use tires equivalent to the
originals in size, quality and performance when
replacement is needed Úpage 399. 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 389.
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.
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.
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 performance characteristics,
resulting in changes to steering, handling, and
braking of your vehicle. This can cause unpre
-
dictable 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 over -
loading 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 speedometer and
odometer readings.

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SERVICING AND MAINTENANCE401
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.
SPARE TIRES — IF EQUIPPED
For restrictions when towing with a spare tire
designated for temporary emergency use
Ú
page 187.
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.
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.
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.
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402SERVICING AND MAINTENANCE
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.
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.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!
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.

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