winter tires RAM 1500 2021 Owners Manual

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.
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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.

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