2008 DODGE RAM 3500 DIESEL inflation pressure

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 (if equipped). 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
ªcold tire inflation pressure.º 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
mi (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
12ÉF (7ÉC) of air temperature change. Keep this in mind
when checking tire pressure inside a garage, especially in
the Winter.
Example: If garage temperature = 68ÉF (20ÉC) and the
outside temperature = 32ÉF (0ÉC) then the cold tire
inflation pressure should be increased by 3 psi (21 kPa),
which equals 1 psi (7 kPa) for every 12ÉF (7ÉC) 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
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 original equipment or an authorized tire
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 accident. Don't 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 an accident. Al-
ways use radial ply tires in sets of four (or six, in 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.
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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 tire,
replace (or repair) the original tire and reinstall on the
vehicle at the first opportunity.
WARNING!
The limited-use spare tires are for emergency use
only. Installation of this limited-use spare tire affects
vehicle handling. With this tire, do not drive more
than 50 mph (80 km/h). Keep inflated to the cold tire
inflation pressure listed on either your tire placard or
limited-use spare tire and wheel assembly. Replace
(or repair) the original tire at the first opportunity
and reinstall it on your vehicle. Failure to do so could
result in loss of vehicle control.
Tire Spinning
When stuck in mud, sand, snow, or ice conditions, do not
spin your vehicle's wheels faster than 30 mph (48 km/h)
or for longer than 30 seconds continuously without
stopping when you are stuck.
For additional information, refer to ªFreeing A Stuck
Vehicleº in Section 6.
WARNING!
Fast spinning tires can be dangerous. Forces gener-
ated by excessive wheel speeds may cause tire dam-
age or failure. A tire could explode and injure some-
one. Do not spin your vehicle's wheels faster than 30
mph (48 km/h) or for more than 30 seconds continu-
ously when you are stuck, and don't let anyone near
a spinning wheel, no matter what the speed.
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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 an accident resulting
in serious injury or death.
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 pressure. The manu-
facturer strongly recommends that you use tires equiva-
lent to the originals in size, quality and performance
when replacement is needed. (Refer to the paragraph on
ªTread Wear Indicatorsº). Refer to the ªTire and Loading
Informationº placard for the size designation of your tire.
The service description and load identification will be
found on the original equipment tire. Failure to use
equivalent replacement tires may adversely affect the
safety, handling, and ride of your vehicle. We recommend
that you contact your original equipment or an autho-
rized tire dealer with any questions you may have on tire
specifications or capability.
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Improper alignment will not cause vehicle vibration.
Vibration may be a result of tire and wheel out-of-
balance. Proper balancing will reduce vibration and
avoid tire cupping and spotty wear.
SUPPLEMENTAL TIRE PRESSURE
INFORMATION Ð IF EQUIPPED
A light load vehicle condition is defined as two passen-
gers [150 lbs (68 kg) each] plus 200 lbs (91 kg) of cargo.
Cold tire inflation pressures for a lightly loaded vehicle
will be found on the face of the driver's door.
TIRE CHAINS
Use ªClass Uº chains on 2500/3500 Ram Trucks, or other
traction aids that meet SAE Type ªUº specifications.
NOTE:Chains must be the proper size for the vehicle,
as recommended by the chain manufacturer.
CAUTION!
To avoid damage to your vehicle, tires or chains, observe the
following precautions:
²Because of limited chain clearance between tires and other
suspension components, it is important that only chains in good
condition are used. Broken chains can cause serious vehicle
damage. Stop the vehicle immediately if noise occurs that could
suggest chain breakage. Remove the damaged parts of the chain
before further use.
²Install chains as tightly as possible and then retighten after
driving about 1/2 mile (0.8 km).
²Do not exceed 45 mph (72 km/h).
²Drive cautiously and avoid severe turns and large bumps,
especially with a loaded vehicle.
²Do not install tire chains on front wheels of 4x2 vehicles.
²Do not drive for a prolonged period on dry pavement.
²Observe the tire chain manufacturer's instructions on method of
installation, operating speed, and conditions for usage. Always
use the lower suggested operating speed of the chain manufac-
turer if different than the speed recommended by the
manufacturer.
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SNOW TIRES
Snow tires should be of the same size and type construc-
tion as the front tires. Consult the manufacturer of the
snow tire to determine any maximum vehicle speed
requirement associated with the tire. These tires should
always be operated at the vehicle maximum capacity
inflation pressures under any load condition.
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.
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 and develop irregular wear patterns. These
effects can be reduced by timely rotation of tires. The
benefits of rotation are especially worthwhile with ag-
gressive tread designs such as those on ON/OFF Road
type tires. Rotation will increase tread life, help to main-
tain mud, snow, and wet traction levels, and contribute to
a smooth, quiet ride.
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TIRE PRESSURE MONITOR SYSTEM (TPMS) Ð IF
EQUIPPED
The Tire Pressure Monitoring System (TPMS) will warn
the driver of a low tire pressure based on the vehicle
recommended cold tire inflation placard pressure. The
placard pressure is defined on the Tire and Loading
Information label. The Tire and Loading Information
label is located on the drivers side B-pillar. Vehicles
equipped to be operated in either the ªmax load inflation
pressureº condition described on the Tire and Loading
Information label or the alternative ªlight load inflation
pressureº condition described on the Supplemental Tire
Pressure Information label, may also be equipped with a
reset switch to choose the appropriate TPMS low pres-
sure warning threshold levels based upon the vehicle
load condition. The Supplemental Tire Pressure Informa-
tion label is located on the rear face of the driver door.
Operation of the ªLight Loadº reset switch is described
later in this manual section.The tire pressure will vary with temperature by approxi-
mately 1 psi (6.9 kPa) for every 12ÉF (6.5ÉC). This means
that when the outside temperature decreases, the tire
pressure will decrease. Tire pressure should always be set
based on cold inflation tire pressure. This is defined as
the tire pressure after a vehicle has not been driven for
more than 3 hours, or driven less than 1 mile after a 3
hour period. For information on how to properly inflate
the vehicle's tires, refer to ºTire Pressureº under ªTires ±
General Informationº in this section. The tire pressure
will also increase as the vehicle is driven - this is normal
and there should be no adjustment for this increased
pressure.
The TPM System will warn the driver of a low tire
pressure if the tire pressure falls below the low pressure
warning threshold for any reason, including low tem-
perature effects, or natural pressure loss through the tire.
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The TPM System will continue to warn the driver of low
tire pressure as long as the condition exists, and will not
turn off until the tire pressure is at or above recom-
mended cold placard pressure. Once the low tire pressure
warning has been illuminated, the tire pressure must be
increased to the recommended cold placard pressure in
order for the TPMS warning lamp to be turned off. The
system will automatically update and the TPMS warning
lamp will extinguish once the updated tire pressures
have been received. The vehicle may need to be driven
for up to 10 minutes above 15 mph (25 km/h) to receive
this information.
As an example, assume your vehicle has a recommended
cold tire inflation placard pressure (parked for more than
3 hours) of 35 psi (241 kPa). If the ambient temperature is
68ÉF (20ÉC) and the measured tire pressure is 30 psi (207
kPa), a temperature drop to 20ÉF (-7ÉC) will decrease the
tire pressure to approximately 26 psi (179 kPa). This tire
pressure is sufficiently low enough to turn ON the TirePressure Monitoring lamp. Driving the vehicle may cause
the tire pressure to rise to approximately 30 psi (207 kPa),
but the Tire Pressure Monitoring lamp will still be ON. In
this situation, the Tire Pressure Monitoring lamp will
turn OFF only after the tires have been inflated to the
vehicle's recommended cold tire placard pressure value.
CAUTION!
The TPMS has been optimized for the original
equipment tires and wheels. TPMS pressures have
been established for the tire size equipped on your
vehicle. Undesirable system operation or sensor
damage may result when using replacement equip-
ment that is not of the same size, type, and/or style.
After-market wheels can cause sensor damage. Do
not use aftermarket tire sealants or balance beads if
your vehicle is equipped with a TPMS, as damage to
the sensors may result.
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