winter tires RAM CHASSIS CAB 2021 Owners Manual

SERVICING AND MAINTENANCE415
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.
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.

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).

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418SERVICING AND MAINTENANCE
(Continued)
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 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.
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)

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SERVICING AND MAINTENANCE419
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 206.
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.
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.8

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