2008 DODGE RAM 3500 DIESEL tires

Dual Rear Wheels
The tires used on dual wheel assemblies should be
matched for wear to prevent overloading one tire in a set.
To check if tires are even, lay a straight edge across all
four tires. The straight edge should touch all the tires.
CAUTION!
3500 Dual Rear Tires have only one approved direc-
tion of rotation. This is to accommodate the asym-
metrical design (tread pattern) of the ON/OFF road
tire and the use of Outline White Letter (OWL) tires.
²When replacing a flat, the spare tire may have to
be remounted on the rim, or installed at a different
location, to maintain the correct placement of the
tire on the wheel relative to the tire/wheel position
on the truck. For example, if the spare is used to
replace an outer rear tire it will have to be re-
mounted on the rim so that the wheel is dished
inward. That way the tread design of asymmetrical
tires and the white writing of the OWL tires will
maintain proper position.
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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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ªLight Loadº Reset Switch Operation ± If
Equipped
²
This vehicle may have different recommended tire
pressure values between the front and rear tires as
shown in both the Tire Loading Information Label and
the Supplemental Tire Pressure Information Label. It is
also equipped to be driven with tire pressures appro-
priate to either a Light Load condition or the vehicle
Max Load condition.
²The ªLight Loadº reset switch will allow the driver to
change between the max load inflation pressure (cold)
low pressure warning threshold and the light load
inflation pressure (cold) low pressure warning thresh-
old depending on the vehicle's load condition. Refer to
the ªSupplemental Tire Pressure Informationº label for
the vehicle's Light Load inflation pressures and ªTire
and Loading Informationº label for the vehicle's Max
Load inflation pressures.
Light Load Reset Switch
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To switch from the max load inflation pressure (cold) low
pressure warning threshold to the light load inflation
pressure (cold) low pressure warning threshold, begin by
placing the ignition switch in the RUN position. Next,
lower all four road tire pressures to the Light Load
Inflation Pressure values as listed on the SupplementalTire Pressure Information label. The Supplemental Tire
Pressure Information label is located on the rear face of
the driver door. Use an accurate tire gauge to check the
tire pressures when lowering all four tire pressures. After
all four tire pressures have been lowered to the Light
Load inflation pressures, press the ªLight Loadº reset
switch. If the ªLight Loadº switch's amber colored LED
turns ON, the TPMS is using the light load inflation
pressure (cold) low pressure warning thresholds.
If the ªLight Loadº reset switch amber colored LED
flashes on and off for 10 seconds, after all four tire
pressures have been lowered to the Light Load inflation
pressures, the pressure in any one of the four tires may
not be at the light load inflation pressure (cold) values as
indicated for the Light Load condition as defined on the
Supplemental Tire Pressure Information label located on
the rear face of the driver door. Using an accurate tire
pressure gauge, re-check the tire pressures for the light
load inflation pressure (cold) value.
Example Supplemental Tire Pressure Label
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WARNING!
It is the driver 's responsibility to change to the max
load inflation pressure (cold) low pressure warning
threshold condition when not driving in the light
load condition as defined as two occupants ( 150 lbs
each) plus 200 pounds of cargo. The vehicle ªLight
Load Definitionº is found in the Supplemental Tire
Pressure Information label located on the rear face of
the driver door. Failure to do so may cause you to lose
control resulting in an accident, causing serious or
fatal injury.
To switch back to the max load inflation pressure (cold)
low pressure warning threshold, press the ªLight Loadº
reset switch. It is not necessary to first fill the tires to the
max load inflation pressure (cold) values to switch the
TPMS system to the max load inflation pressure (cold)low pressure warning threshold. If after pressing the
ªLight Loadº reset switch and tire pressures are below
the max load inflation pressure (cold) low pressure
warning thresholds, the TPMS low pressure warning
telltale lamp located in the Instrument Cluster will turn
ON and a chime will sound. The tire pressures are now
required to be inflated to the max load inflation pressure
(cold) values described on the Tire and Loading Informa-
tion label. The Tire and Loading Information label is
located on the drivers side B-pillar. If the ªLight Loadº
reset switch LED turns OFF the TPMS has been reset and
the TPMS is using the max load inflation pressure (cold)
low pressure warning thresholds.
Tire Pressure Monitor System Components
The Tire Pressure Monitor System (TPMS) uses wireless
technology with wheel rim mounted electronic sensors to
monitor tire pressure levels. Sensors, mounted to each
wheel as part of the valve stem, transmit tire pressure
readings to the Receiver Module.
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NOTE:It is particularly important, for you to check the
tire pressure in all of your tires regularly and to maintain
the proper pressure.
The Tire Pressure Monitoring System (TPMS) consists of
the following components:
²Receiver Module
²4 Wheel Sensors
²2 Trigger Modules (mounted in the front wheel-wells)
²ªLight Loadº Reset Switch (located in the instrument
panel)
²Tire Pressure Monitoring Telltale Lamp
Tire Pressure Monitoring Low Pressure Warnings
The Tire Pressure Monitoring Telltale Lamp will
illuminate in the instrument cluster, and an au-
dible chime will be activated when one or more of
the four active road tire pressures are low. Should this
occur, you should stop as soon as possible, check the
inflation pressure of each tire on your vehicle and inflate
each tire to the vehicle's recommended cold placard
pressure value. The system will automatically update
and the Tire Pressure Monitoring 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.
Check TPMS Warnings
The Tire Pressure Monitoring Telltale Warning Light
located in the Instrument Cluster will flash on and off for
75 seconds and will remain on solid when a system fault
is detected. The system fault will also sound a chime. If
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the ignition key is cycled, this sequence will repeat,
providing the system fault still exists. A system fault can
occur by any of the following scenarios:
1. Signal interference due to electronic devices or driving
next to facilities emitting the same Radio Frequencies as
the TPM sensors.
2. Installing aftermarket window tinting that affects ra-
dio wave signals.
3. Accumulation of snow or ice around the wheels or
wheel housings.
4. Using tire chains on the vehicle.
5. Using wheels/tires not equipped with TPM sensors.
6. Loss of communication with the trigger modules or
tire pressure monitoring sensors.
NOTE: Your vehicle is equipped with a non-matching
full size spare wheel and tire assembly.1. This spare tire does not have a tire pressure monitor-
ing sensor. Therefore, the TPMS will not monitor the tire
pressure in the spare tire.
2. If you install the full size spare tire in place of a road
tire that has a pressure below the low-pressure warning
limit, upon the next ignition key cycle, a chime will
sound and the TPM Telltale Light will still turn ON due
to the low tire.
3. However, after driving the vehicle for up to 10 min-
utes above 15 mph (25 km/h), the TPM Telltale Light will
flash on and off for 75 seconds and then remain on solid.
4. For each subsequent ignition key cycle, a chime will
sound and the TPM Telltale Light will flash on and off for
75 seconds and then remain on solid.
5. Once you repair or replace the original road tire, and
reinstall it on the vehicle in place of the full size spare tire,
the TPMS will update automatically and the TPM Telltale
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