2008 DODGE RAM 3500 GAS service

ONBOARD DIAGNOSTIC SYSTEM (OBD II)
Your vehicle is equipped with a sophisticated onboard
diagnostic system called OBDII. This system monitors
the performance of the emissions, engine, and automatic
transmission control systems. When these systems are
operating properly, your vehicle will provide excellent
performance and fuel economy, as well as engine emis-
sions well within current government regulations.
If any of these systems require service, the OBD II system
will turn on the Malfunction Indicator Light (MIL). It will
also store diagnostic codes and other information to
assist your service technician in making repairs. Al-
though your vehicle will usually be drivable and not
need towing, see your authorized dealer for service as
soon as possible.CAUTION!
Prolonged driving with the Malfunction Indicator
Light (MIL) on could cause further damage to the
emission control system. It could also affect fuel
economy and drivability. The vehicle must be ser-
viced before any emissions tests can be performed.
If the Malfunction Indicator Light (MIL) is flashing,
severe catalytic converter damage and power loss
will soon occur. Immediate service is required.
Loose Fuel Filler Cap Message
If the vehicle's diagnostic system determines that the fuel
filler cap in loose, improperly installed, or damaged, a
GASCAP message will be displayed in the instrument
cluster. Tighten the gas cap until a ªclickingº sound is
heard. This is an indication that the gas cap is properly
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tightened. Press the odometer reset button to turn the
message off. If the problem persists, the message will
appear the next time the vehicle is started. This might
indicate a damaged cap. If the problem is detected twice
in a row, the system will turn on the Malfunction
Indicator Light (MIL). Resolving the problem will turn
the MIL light off.
EMISSIONS INSPECTION AND MAINTENANCE
PROGRAMS
In some localities, it may be a legal requirement to pass
an inspection of your vehicle's emissions control system.
Failure to pass could prevent vehicle registration.
For states which have an Inspection and Mainte-
nance (I/M) requirement, this check verifies the
following: the Malfunction Indicator Lamp (MIL)
is functioning and is not on when the engine is running,
and that the On Board Diagnostic (OBD) system is ready
for testing.Normally, the OBD system will be ready. The OBD
system maynotbe ready if your vehicle was recently
serviced, if you recently had a dead battery, or a battery
replacement. If the OBD system should be determined
not ready for the I/M test, your vehicle may fail the test.
Your vehicle has a simple ignition key actuated test
which you can use prior to going to the test station. To
check if your vehicle's OBD system is ready, you must do
the following:
1. Insert your ignition key into the ignition switch.
2. Turn the ignition to the ON position, but do not crank
or start the engine.
3. If you crank or start the engine, you will have to start
this test over.
4. As soon as you turn your key to the ON position, you
will see your MIL symbol come on as part of a normal
bulb check.
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5. Approximately 15 seconds later, one of two things will
happen:
a. The MIL will blink for approximately five seconds
and then remain on until the first engine crank or the
key is turned off. This means that your vehicle's OBD
system isnot readyand you shouldnotproceed to the
I/M station.
b. The MIL will remain fully illuminated until the first
engine crank or the key is turned off. This means that
your vehicle's OBD system isreadyand you can
proceed to the I/M station.
If your OBD system isnot ready,you should see your
authorized dealer or repair facility. If your vehicle was
recently serviced, or had a battery failure or replacement,
you may need to do nothing more than drive your
vehicle as you normally would in order for your OBD
system to update. A recheck with the above test routine
may then indicate that the system is now ready.Regardless of whether your vehicle's OBD system is
ready or not ready, if the MIL symbol is illuminated
during normal vehicle operation, you should have your
vehicle serviced before going to the I/M station. The I/M
station can fail your vehicle because the MIL symbol is on
with the engine running.
REPLACEMENT PARTS
Use of genuine Mopartparts for normal/scheduled
maintenance and repairs is highly recommended to en-
sure the designed performance. Damage or failures
caused by the use of non-Mopartparts for maintenance
and repairs will not be covered by the manufacturer's
warranty.
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AUTHORIZED DEALER SERVICE
Your authorized dealer has the qualified service person-
nel, special tools and equipment to perform all service
operations in an expert manner. Service manuals are
available which include detailed service information for
your vehicle. Refer to these manuals before attempting
any procedure yourself.
NOTE:Intentional tampering with emissions control
systems can result in civil penalties being assessed
against you.
WARNING!
You can be badly injured working on or around a
motor vehicle. Do only that service work for which you
have the knowledge and the proper equipment. If you
have any doubt about your ability to perform a service
job, take your vehicle to a competent mechanic.
MAINTENANCE PROCEDURES
The pages that follow contain therequiredmaintenance
services determined by the engineers who designed your
vehicle.
Besides the maintenance items for which there are fixed
maintenance intervals, there are other items that should
operate satisfactorily without periodic maintenance.
However, if a malfunction of these items does occur, it
could adversely affect the engine or vehicle performance.
These items should be inspected if a malfunction is
observed or suspected.
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NOTE:Vehicles equipped with a 5.7L engine must use
SAE 5W-20 oil. Failure to do so may result in improper
operation of the Multi-Displacement System (MDS). Re-
fer to ªMulti-Displacement Systemº under ªStarting and
Operatingº in Section 5.
NOTE:For 2500/3500 trucks with a 5.7L engine oper-
ating under a gross combined weight rating of 14,000 lbs.
or greater, SAE 5W-30 engine oil is recommended for all
operating temperatures.
Lubricants, which do not have both the engine oil certi-
fication mark and the correct SAE viscosity grade num-
ber, should not be used.
Synthetic Engine Oils
You may use synthetic engine oils if the recommended oil
quality requirements are met, and the recommended
maintenance intervals for oil and filter changes are
followed.
Materials Added to Engine Oil
The manufacturer strongly recommends against the ad-
dition of any additives (other than leak detection dyes) to
the engine oil. Engine oil is an engineered product and its
performance may be impaired by supplemental addi-
tives.
Disposing of Used Engine Oil and Oil Filters
Care should be taken in disposing of used engine oil and
oil filters from your vehicle. Used oil and oil filters,
indiscriminately discarded, can present a problem to the
environment. Contact your authorized dealer, service
station, or governmental agency for advice on how and
where used oil and oil filters can be safely discarded in
your area.
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Engine Oil Filter
The engine oil filter should be replaced at every engine
oil change.
Engine Oil Filter Selection
The manufacturer's engines have a full-flow type oil
filter. Use a filter of this type for replacement. The quality
of replacement filters varies considerably. Only high-
quality filters should be used to assure most efficient
service. Mopar Engine Oil Filters are a high-quality oil
filter and are recommended.
Drive Belts Ð Check Condition and Tension
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.
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 ªSpark Plugsº under ªFluids, Lubri-
cants and Genuine Partsº in Section 7.
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CAUTION!
Damage to the catalytic converter can result if your
vehicle is not kept in proper operating condition. In
the event of engine malfunction, particularly involv-
ing engine misfire or other apparent loss of perfor-
mance, have your vehicle serviced promptly. Contin-
ued operation of your vehicle with a severe
malfunction could cause the converter to overheat,
resulting in possible damage to the converter and the
vehicle.
NOTE:Intentional tampering with emissions control
systems can result in civil penalties being assessed
against you.
WARNING!
A hot exhaust system can start a fire if you park over
materials that can burn. Such materials might be
grass or leaves coming into contact with your exhaust
system. Do not park or operate your vehicle in areas
where your exhaust system can contact anything that
can burn.
In unusual situations involving grossly malfunctioning
engine operation, a scorching odor may indicate severe
and abnormal catalyst overheating. If this occurs, the
vehicle should be stopped, the engine shut off and the
vehicle allowed to cool. Thereafter, service, including a
tune-up to manufacturer's specifications, should be ob-
tained immediately.
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Air Conditioner Maintenance
For best possible performance, your air conditioner
should be checked and serviced by an Authorized Dealer
at the start of each warm season. This service should
include cleaning of the condenser fins and a performance
test. Drive belt tension should also be checked at this
time.
NOTE:Refer to Section 3 of the Warranty Information
book for further warranty information.WARNING!
²Use only refrigerants and compressor lubricants
approved by the manufacturer for your air condi-
tioning system. Some unapproved refrigerants are
flammable and can explode, injuring you. Other
unapproved refrigerants or lubricants can cause
the system to fail, requiring costly repairs.
²The air conditioning system contains refrigerant
under high pressure. To avoid risk of personal
injury or damage to the system, adding refrigerant
or any repair requiring lines to be disconnected
should be done by an experienced repairman.
NOTE:Use only manufacturer approved A/C System
Sealers, Stop Leak Products, Seal Conditioners, Compres-
sor Oil, or Refrigerants.
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