winter tires Ram 1500 2013 Owner's Manual

once a month. Use a good quality pocket-type gauge to
check tire pressure. Do not make a visual judgement
when determining proper inflation. Radial tires may look
properly inflated even when they are under-inflated.
CAUTION!
After inspecting or adjusting the tire pressure, al-
ways reinstall the valve stem cap. This will prevent
moisture and dirt from entering the valve stem,
which could damage 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 a three hour period. The cold tire
inflation pressure must not exceed the maximum infla-
tion 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.
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Tire Pressures For High Speed Operation
The manufacturer advocates driving at safe speeds and
within posted speed limits. Where speed limits or condi-
tions 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 opera-
tion. Refer to your authorized tire or original equipment
vehicle dealer for recommended safe operating speeds,
loading and cold tire inflation pressures.
WARNING!
High speed driving with your vehicle under maxi-
mum 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).
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. Al-
ways use radial ply tires in sets of four (or six, in the
case of trucks with dual rear wheels). Never combine
them with other types of tires.
Cuts and punctures in radial tires are repairable only in
the tread area because of sidewall flexing. Consult your
authorized tire dealer for radial tire repairs.
All Season Tires – If Equipped
All Season tires provide traction for all seasons (spring,
summer, fall and winter). Traction levels may vary be-
tween different all season tires. All season tires can be
identified by the M+S, M&S, M/S or MS designation on
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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. Summer tires will 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 pro-
hibit studded tires; therefore, local laws should be
checked before using these tire types.
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