2008 DODGE RAM 2500 GAS Owners Manual

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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Light will turn OFF, as long as no tire pressure is below
the low-pressure warning limit in any of the four active
road tires. The vehicle may need to be driven for up to 10
minutes above 15 mph (25 km/h) in order for the TPMS
to receive this information.
General Information
This device complies with part 15 of the FCC rules and
RSS 210 of Industry Canada. Operation is subject to the
following conditions:
²This device may not cause harmful interference.
²This device must accept any interference received,
including interference that may cause undesired op-
eration.
The tire pressure sensors are covered under one of the
following licenses:
United States.....................KR5S120123
Canada........................2671-S120123
FUEL REQUIREMENTS
All engines (except 5.7L engines) are de-
signed to meet all emissions regulations
and provide excellent fuel economy and
performance when using high-quality un-
leaded ªregularº gasoline having an oc-
tane rating of 87. The use of premium
gasoline is not recommended. Under nor-
mal conditions, the use of premium gasoline will not
provide a benefit over high-quality regular gasolines, and
in some circumstances may result in poorer performance.
The 5.7L engine is designed to meet all
emissions regulations and provide satisfac-
tory fuel economy and performance when
using high-quality unleaded gasoline hav-
ing an octane range of 87 to 89. The manu-
facturer recommends the use of 89 octane
All Engines
Except 5.7L
5.7L Engines
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for optimum performance. The use of premium gasoline
is not recommended. Under normal conditions, the use of
premium gasoline will not provide a benefit over high-
quality regular and mid-grade gasolines, and in some
circumstances may result in poorer performance.
Light spark knock at low engine speeds is not harmful to
your engine. However, continued heavy spark knock at
high speeds can cause damage and immediate service is
required.
Poor quality gasoline can cause problems such as hard
starting, stalling and hesitations. If you experience these
symptoms, try another brand of ªregularº gasoline be-
fore considering service for the vehicle.
Over 40 auto manufacturers worldwide have issued and
endorsed consistent gasoline specifications (the World-
wide Fuel Charter, WWFC) to define fuel properties
necessary to deliver enhanced emissions, performanceand durability for your vehicle. We recommend the use
of gasolines that meet the WWFC specifications if they
are available.
Reformulated Gasoline
Many areas of the country require the use of cleaner
burning gasoline referred to as ªReformulated Gasolineº
Reformulated gasolines contain oxygenates, and are spe-
cifically blended to reduce vehicle emissions and im-
prove air quality.
The manufacturer supports the use of reformulated gaso-
lines. Properly-blended reformulated gasolines will pro-
vide excellent performance and durability of engine and
fuel system components.
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Gasoline/Oxygenate Blends
Some fuel suppliers blend unleaded gasoline with oxy-
genates such as 10% ethanol, MTBE, and ETBE. Oxygen-
ates are required in some areas of the country during the
Winter months to reduce carbon monoxide emissions.
Fuels blended with these oxygenates may be used in
your vehicle.
CAUTION!
DO NOT use gasolines containing Methanol or E85
Ethanol. Use of these blends may result in starting
and drivability problems and may damage critical
fuel system components.
NOTE: 4.7L Engine Ð If Equipped, is now rated for
E85 Ethanol use. Only vehicles with the E-85 fuel filler
door label can operate on E-85. For more information,
refer to ªFlexible Fuelº in this section.Problems that result from using methanol/gasoline or
E85 Ethanol blends are not the responsibility of the
manufacturer. While MTBE is an oxygenate made from
Methanol, it does not have the negative effects of Metha-
nol.
MMT In Gasoline
MMT is a manganese containing metallic additive that is
blended into some gasoline to increase octane. Gasoline
blended with MMT provides no performance advantage
beyond gasoline of the same octane number without
MMT. Gasoline blended with MMT reduces spark plug
life and reduces emission system performance in some
vehicles. The manufacturer recommends that gasoline
without MMT be used in your vehicle. The MMT content
of gasoline may not be indicated on the gasoline pump,
therefore, you should ask your gasoline retailer whether
or not the gasoline contains MMT. It is even more
important to look for gasolines without MMT in Canada,
because MMT can be used at levels higher than those
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allowed in the United States. MMT is prohibited in
Federal and California reformulated gasoline.
Materials Added To Fuel
All gasolines sold in the United States are required to
contain effective detergent additives. Use of additional
detergents or other additives is not needed under normal
conditions and would result in unnecessary cost. There-
fore, you should not have to add anything to the fuel.
Fuel System Cautions
CAUTION!
Follow these guidelines to maintain your vehicle's
performance:
²The use of leaded gas is prohibited by Federal law.
Using leaded gasoline can impair engine performance,
damage the emission control system.
²An out-of-tune engine, or certain fuel or ignition
malfunctions, can cause the catalytic converter to
overheat. If you notice a pungent burning odor or
some light smoke, your engine may be out of tune or
malfunctioning and may require immediate service.
Contact your authorized dealer for service assistance.
²When pulling a heavy load or driving a fully-loaded
vehicle when the humidity is low and the temperature
is high, use a premium unleaded fuel to help prevent
spark knock. If spark knock persists, lighten the load,
or engine piston damage may result.
²The use of fuel additives which are now being sold as
octane enhancers is not recommended. Many of these
products contain high concentrations of methanol.
Fuel system damage or vehicle performance problems
resulting from the use of such fuels or additives is not
the responsibility of the manufacturer.
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