2008 DODGE RAM 4500 CHASSIS CAB gas mileage

The two trip odometers show individual trip mileage. To
switch from odometer to trip odometers, press and
release the Trip Odometer button.
To reset a trip odometer, display the desired trip odom-
eter to be reset then push and hold the button until the
display resets (approximately 2 seconds).
Vehicle Warning Messages
For non±Electronic Vehicle Information Center (EVIC)
equipped vehicles, and the appropriate conditions exist,
messages such as ªdoorº (indicates that a door(s) may be
ajar), ªhoodº (if the hood is open or ajar, on vehicles with
remote start), ªgASCAPº (which indicates that your gas
cap is possibly loose or damaged),9CHANgE OILº
(indicates that the engine oil should be change), ªLo-
WASHº (low washer fluid),º LoCOOLº (low engine
coolant level) and ªnoFUSEº (indicates that the IOD fuse
is removed from the Integrated Power Module), will
display in the odometer.NOTE:If the vehicle is equipped with an EVIC, most
warnings will display in the EVIC. For additional infor-
mation, refer to ªElectronic Vehicle Information Center
(EVIC) Ð If Equippedº in Section 3.
NOTE:There is also an engine hour function. This
indicates the total number of hours the engine has been
running. To display the engine hours perform the follow-
ing: Place the ignition in RUN, but do not start the
engine. With the odometer value displayed, hold the trip
button down for a period of 6 seconds. The odometer will
change to trip value first, then it will display the engine
hour value. The engine hours will be displayed for a
period of 30 seconds until the ignition is turned off or the
engine is started.
Change Oil Message
Your vehicle is equipped with an engine oil change
indicator system. The ªChange Oilº message will flash in
the instrument cluster odometer for approximately 12
178 UNDERSTANDING YOUR INSTRUMENT PANEL

Drive Belts (Gas Engines)
Belt tension is controlled by means of an automatic
tensioner. No belt tension adjustments are required.
However, belt and belt tensioner condition should be
inspected at the specified intervals and replaced if re-
quired. See your authorized dealer for service.
At the mileage indicated in the maintenance schedule, all
belts and tensioner should be checked for condition.
Improper belt tension can cause belt slippage and failure.
Belts should be inspected for evidence of cuts, cracks,
glazing or frayed cords and replaced if there is indication
of damage which could result in belt failure. Low gen-
erator belt tension can cause battery failure.
Also check belt routing to make sure there is no interfer-
ence between the belts and other engine components.
Drive Belt (Diesel Engines)
Inspection
Check the belt for intersecting cracks.
²Transverse (across the belt width) cracks are accept-
able.
²Longitudinal (direction of belt length) cracks that
intersect with transverse cracks are NOT acceptable.
Replace the belt if it has unacceptable cracks, is frayed or
has pieces of material missing.
The engine speed sensor, located near the damper, should
be inspected for damage if a belt is frayed.
Engine Air Cleaner Filter (Gas Engines)
Follow the appropriate Maintenance Schedule for recom-
mended Air Cleaner Replacement intervals.
MAINTAINING YOUR VEHICLE 413
7

mixture in excess of 5% can negatively impact the on-
engine fuel filter's ability to separate water from the fuel,
resulting in high pressure fuel system corrosion or dam-
age.
NOTE:As sufficient testing has not been completed,
ethanol blends are not recommended or approved for use
with your Cummins Diesel equipped vehicle.
NOTE:In addition, commercially available fuel addi-
tives are not necessary for the proper operation of your
Cummins Diesel equipped vehicle.
Engine Fuel Filter (Gas Engines)
A plugged fuel filter can cause stalling, limit the speed at
which a vehicle can be driven or cause hard starting.
Should an excessive amount of dirt accumulate in the
fuel tank, frequent filter replacement may be necessary.
Spark Plugs (Gas Engines)
Spark plugs must fire properly to assure engine perfor-
mance and emission control. New plugs should be in-
stalled at the specified mileage. The entire set should be
replaced if there is any malfunction due to a faulty spark
plug, malfunctioning spark plugs can damage the cata-
lytic converter. For proper type of replacement spark
plugs, refer to the Fluids, Lubricants and Genuine Parts
section in this manual.
Catalytic Converter (Gas Engines)
The catalytic converter requires the use of unleaded fuel
only. Leaded gasoline will destroy the effectiveness of the
catalyst as an emission control device.
Under normal operating conditions, the catalytic con-
verter will not require maintenance. However, it is im-
portant to keep the engine properly tuned to assure
proper catalyst operation and prevent possible catalyst
damage.
420 MAINTAINING YOUR VEHICLE

Emission-Related Components (Gas Engines)
Positive Crankcase (PCV) Valve
Proper operation of the crankcase ventilation system
requires that the PCV valve be free of sticking or plug-
ging from deposits. Deposits can accumulate in the PCV
valve and passages with increasing mileage. Have the
PCV valve, hoses, and passages checked for proper
operation at the intervals specified. If the valve is
plugged or sticking, replace with a new valveÐdo not
attempt to clean the old PCV valve!Check the ventila-
tion hoses for indications of damage, weepage or plug-
ging with deposits. Replace if necessary.
Maintenance Free Battery (Gas Engines)
The top of the maintenance free battery is permanently
sealed. You will never have to add water, nor is periodic
maintenance required.
WARNING!
²Battery fluid is a corrosive acid solution and can
burn or even blind you. Don't allow battery fluid
to contact your eyes, skin or clothing. Don't lean
over a battery when attaching clamps. If acid
splashes in eyes or on skin, flush the area imme-
diately with large amounts of water.
²Battery gas is flammable and explosive. Keep
flame or sparks away from the battery. Don't use a
booster battery or any other booster source with an
output greater than 12 volts. Don't allow cable
clamps to touch each other.
²Battery posts, terminals and related accessories
contain lead and lead compounds. Wash hands
after handling.
MAINTAINING YOUR VEHICLE 425
7

²Do not change the thermostat for summer or winter
operation. If replacement is ever necessary, install
ONLY the correct type thermostat. Other designs may
result in unsatisfactory coolant performance, poor gas
mileage, and increased emissions.
Fan
Inspection
Check the fan for cracks and bent or broken blades. If any
of these conditions exist, you must replace the fan. Make
sure it is securely mounted.
NOTE:This service procedure must be performed by a
trained service technician. Make arrangements with your
authorized Dodge Truck Dealer for this inspection.
Charge Air Cooler Ð Inter-Cooler (Diesel
Engines)
The charge air cooler is positioned between the radiator
and the air conditioner condenser. Air enters the engine
through the air cleaner and passes through the turbo-
charger where it is pressurized. This pressurized air
rapidly reaches high temperature. The air is then directed
through a hose to the charge air cooler and through
another hose to the intake manifold of the engine. The air
entering the engine has been cooled by about 50 to 100
degrees Fahrenheit. This cooling process enables more
efficient burning of fuel resulting in fewer emissions.
To guarantee optimum performance of the system, keep
the surfaces of the charge air cooler, condenser and
radiator clean and free of debris. Periodically check the
hoses leading to and from the charge air cooler for cracks
or loose clamps resulting in loss of pressure and reduced
engine performance.
MAINTAINING YOUR VEHICLE 439
7

Noise Systems Maintenance Chart and Service LogMaintenance Log and Service Chart (Gas Engines)Insert
Month, Day, Year under column mileage closest to the mileage at which service was performed.
MILES 6,000 12,000 18,000 24,000 30,000 36,000 42,000 48,000
KILOMETERS 9 600 19 000 29 000 36 000 48 000 58 000 67 000 77 000
Exhaust system-inspect
Air cleaner assembly-inspect
ODOMETER READING
PERFORMED BY
PERFORMED AT
MILES 54,000 60,000 66,000 72,000 78,000 84,000 90,000 96,000
KILOMETERS 87 000 96 000 106 000 116 000 126 000 135 000 145 000 154 000
Exhaust system-inspect
Air cleaner assembly-inspect
ODOMETER READING
PERFORMED BY
PERFORMED AT
MAINTAINING YOUR VEHICLE 455
7

Required Maintenance Intervals
Perform Maintenance Every(Where time and mileage
are listed, follow the interval that occurs first.)
Maintenance Items Miles Kilometers or Months
Change the engine oil and engine oil filter. 6,000 10 000 6
Rotate Tires. 6,000 10 000 6
Lubricate outer tie rod ends. 6,000 10 000 6
Lube Front Drive Shaft Fitting (4x4 only). 6,000 10 000 6
If using your vehicle for any of the following: Dusty
or off-road conditions. Inspect the engine air cleaner
filter, replace if necessary.12,000 20 000 12
Inspect the brake linings, replace if necessary. 12,000 20 000 12
Inspect the front and rear axle fluid, change if using
your vehicle for police, taxi, fleet, off-road or frequent
trailer towing (Gas Engine Only).18,000 30 000 18
Inspect the CV Joints. Perform the first inspection at
12,000 miles (20 000 km) or 12 months.24,000 40 000 24
494 MAINTENANCE SCHEDULES
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