2008 DODGE RAM 2500 DIESEL wheel

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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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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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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Gross Vehicle Weight Rating (GVWR)
The GVWR is the total permissible weight of your vehicle
including driver, passengers, vehicle, options and cargo.
The label also specifies maximum capacities of front and
rear axle systems (GAWR). Total load must be limited so
GVWR and front and rear GAWR are not exceeded.
Payload
The payload of a vehicle is defined as the allowable load
weight a truck can carry, including the weight of the
driver, all passengers, options and cargo.
Gross Axle Weight Rating (GAWR)
The GAWR is the maximum permissible load on the front
and rear axles. The load must be distributed in the cargo
area so that the GAWR of each axle is not exceeded.Each axle GAWR is determined by the components in the
system with the lowest load carrying capacity (axle,
springs, tires or wheels). Heavier axles or suspension
components sometimes specified by purchasers for in-
creased durability does not necessarily increase the vehi-
cle's GVWR.
Tire Size
The tire size on the Label represents the actual tire size on
your vehicle. Replacement tires must be equal to the load
capacity of this tire size.
Rim Size
This is the rim size that is appropriate for the tire size
listed.
Inflation Pressure
This is the cold tire inflation pressure for your vehicle for
all loading conditions up to full GAWR.
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Fifth-Wheel Hitch
A special high platform with a coupling that mounts over
the rear axle of the tow vehicle in the truck bed. Connects
a vehicle and fifth-wheel trailer with a coupling king pin.
Gooseneck Hitch
The gooseneck hitch employs a pivoted coupling arm
which attaches to a ball mounted in the bed of a pickup
truck. The coupling arm connects to the hitch mounted
over the rear axle in the truck bed.
Trailer Hitch Classification
The rear bumper is intended to tow trailers up to 2,000
lbs (907 kg) without added equipment or alterations to
the standard equipment. Your vehicle may be factory
equipped for safe towing of trailers weighing over 2,000
lbs (907 kg) with the optional Trailer Tow Prep Package.
See your dealer for package content.
The following chart provides the industry standard for
the maximum trailer weight a given trailer hitch class cantow and should be used to assist you in selecting the
correct trailer hitch for your intended towing condition.
Refer to ªTrailer Towing Weights (Maximum Trailer
Weight Ratings)º for the website address that contains
the necessary information for your specific drivetrain.
Trailer Hitch Classification
Class Max. GTW
(Gross Trailer Wt.)
Class I - Light Duty 2,000 lbs (907 kg)
Class II - Medium
Duty3,500 lbs (1587 kg)
Class III - Heavy Duty 5,000 lbs (2268 kg)
Class IV - Extra
Heavy Duty10,000 lbs (4540 kg)
Fifth Wheel/
GooseneckGreater than 10,000 lbs
(4540 kg)
All trailer hitches should be professionally installed on
your vehicle.
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Trailer Towing Weights (Maximum Trailer Weight
Ratings)
NOTE:For additional trailer towing information (maxi-
mum trailer weight ratings) refer to the following website
addresses:
²http:// www.dodge.com/towing.
²http:// www.dodge.ca(Canada).
Trailer and Tongue Weight
Always load a trailer with 60% to 65% of the weight in
the front of the trailer. This places 10% to 15% of the
Gross Trailer Weight (GTW) on the tow hitch of your
vehicle. Loads balanced over the wheels or heavier in the
rear can cause the trailer to swayseverelyside to side
which will cause loss of control of vehicle and trailer.
Failure to load trailers heavier in front is the cause of
many trailer accidents.Never exceed the maximum tongue weight stamped on
your bumper or trailer hitch.
Consider the following items when computing the
weight on the rear axle of the vehicle:
²The tongue weight of the trailer.
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