2008 DODGE RAM 3500 GAS catalytic converter

CAUTION!
Prolonged driving with the MIL on could cause
damage to the engine control system. It also could
affect fuel economy and drivability.
If the MIL is flashing, severe catalytic converter
damage and power loss will soon occur. Immediate
service is required.
19. Brake System Warning Light
This light illuminates when the ignition key is turned to
the ON position and remains on for a few seconds. If the
light stays on longer, it may be an indication that the
parking brake has not been released. This light will
illuminate if the brake fluid is low, especially when
braking or accelerating hard. This light will illuminate if
the ABS indicator light has a malfunction. This light will
flash if the engine is running and the parking brake is on.If the light remains on when the parking brake is
released, it indicates a possible brake hydraulic system
malfunction. In this case, the light will remain on until
the cause is corrected.
If brake failure is indicated, immediate repair is necessary
and continued operation of the vehicle in this condition is
dangerous.
Acceleration which causes the rear wheels to slip for a
period of time may result in the red brake light illumi-
nating and a brake switch code being set on ABS
equipped vehicles. Depressing the brake pedal should
extinguish the red brake light.
20. ABS Warning Light
This light monitors the Anti-Lock Brake System
which is described elsewhere in this manual. This
light will come on when the ignition key is turned to the
ON position and may stay on for five seconds. If the ABS
light remains on or comes on during driving, it indicates
202 UNDERSTANDING YOUR INSTRUMENT PANEL

WARNING!
Do not attempt to push or tow your vehicle to get it
started. Vehicles equipped with an automatic trans-
mission cannot be started this way. Unburned fuel
could enter the catalytic converter and once the
engine has started, ignite and damage the converter
and vehicle.
If the vehicle has a discharged battery, booster cables
may be used to obtain a start from a booster battery
or the battery in another vehicle. This type of start
can be dangerous if done improperly. Refer to ªJump
Startingº in Section 6.If the engine has been flooded, it may start to run, but not
have enough power to continue running when the key is
released. If this occurs, continue cranking with the accel-
erator pedal pushed all the way to the floor. Release the
accelerator pedal and the key once the engine is running
smoothly.
If the engine shows no sign of starting after two 15-
second periods of cranking with the accelerator pedal
held to the floor, the normal starting procedure should be
repeated.
After Starting
The idle speed is automatically controlled and will de-
crease as the engine warms up.
STARTING AND OPERATING 281
5

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.
374 STARTING AND OPERATING

HOISTING
A conventional floor jack may be used at the jacking
locations. Refer to the graphics that show jacking loca-
tions. However, a floor jack or frame hoist must never be
used on any other parts or the underbody.
CAUTION!
Never use a floor jack directly under the differential
housing of a loaded truck or damage to your vehicle
may result.
JUMP-STARTING PROCEDURES
Do not attempt to push or tow your vehicle to get it
started. Vehicles equipped with an automatic transmis-
sion cannot be started this way. Pushing or towing a
vehicle equipped with a manual transmission may over-
heat and damage the catalytic converter. Also, there is a
greater risk of an accident when a vehicle is being pushed
or towed. If the vehicle has a discharged battery, booster
cables may be used to obtain a start from a booster
battery or the battery in another vehicle. This type of start
can be dangerous if done improperly, so follow this
procedure carefully.
434 WHAT TO DO IN EMERGENCIES

MAINTAINING YOUR VEHICLE
CONTENTS
mEngine CompartmentÐ 3.7L...............444
mEngine CompartmentÐ 4.7L...............445
mEngine CompartmentÐ 5.7L...............446
mOnboard Diagnostic System (OBD II).........447
NLoose Fuel Filler Cap Message............447
mEmissions Inspection And Maintenance
Programs............................448
mReplacement Parts......................449
mAuthorized Dealer Service................450mMaintenance Procedures..................450
NEngine Oil..........................451
NEngine Oil Filter......................454
NDrive Belts Ð Check Condition And Tension . . 454
NSpark Plugs (Gas Engines)...............454
NEngine Air Cleaner Filter................455
NEngine Fuel Filter.....................455
NCatalytic Converter....................455
NEmission-Related Components............457
7

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
MAINTAINING YOUR VEHICLE 447
7

Engine Air Cleaner Filter
Follow the Maintenance Schedule for recommended En-
gine Air Cleaner Filter change intervals.
WARNING!
The air induction system (air cleaner, hoses, etc.) can
provide a measure of protection in the case of engine
backfire. Do not remove the air induction system (air
cleaner, hoses, etc.) unless such removal is necessary
for repair or maintenance. Make sure that no one is
near the engine compartment before starting the
vehicle with the air induction system (air cleaner,
hoses, etc.) removed. Failure to do so can result in
serious personal injury.
Engine Fuel Filter
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.
Catalytic Converter
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.
MAINTAINING YOUR VEHICLE 455
7

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.
456 MAINTAINING YOUR VEHICLE