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The best time to check the oil level is approximately 5
minutes after a fully warmed up engine is turned off or
before starting the engine after it has sat overnight.
Checking the oil while the vehicle is on level ground also
will improve the accuracy of the oil level readings. Add
oil only when the level is below the SAFE mark.Changing Engine Oil
Road conditions and your kind of driving affects the
interval at which your oil should be changed.
IfANYof the following apply to you, then change your
engine oil every 3,000 miles (5 000 km) or 3 months,
whichever comes first and follow the maintenance rec-
ommendations in ScheduleB.
²Day or night temperatures are below 32ÉF (0ÉC)
²Stop and go driving
²Extensive engine idling
²Driving in dusty conditions
²Short trip driving of less than 10 miles (16.2 km)
²More than 50% of your driving is at sustained high
speeds during hot weather, above 90ÉF (32ÉC)
²Taxi, Police, or delivery service (commercial service)
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²Trailer towing
²Off-road or desert driving
²If equipped for and operating with E±85 (ethanol) fuel
If none of these apply to you, then change your engine oil
every 6,000 miles (10 000 km) or 6 months, whichever
comes first and follow the maintenance recommenda-
tions in ScheduleA.
CAUTION!
Overfilling the crankcase will cause oil aeration and
loss of oil pressure. This could damage your engine.
Engine Oil Selection
For best performance and maximum protection under all
types of operating conditions, select only engine oils that
meet the American Petroleum Institute (API) certification
and SAE viscosity standards.
American Petroleum Institute (API) Engine Oil
Identification Symbol
This symbol on the front of an oil
container means that the oil has
been certified by the American
Petroleum Institute (API) to meet
all the lubrication requirements
specified by the manufacturer.
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Engine Oil Viscosity Chart
The proper SAE viscosity grade of engine oil should be
selected based on the following recommendation and be
within the operating temperature shown in the engine oil
viscosity chart.
Synthetic Engine Oils
There are a growing number of engine oils being pro-
moted as either synthetic or semi-synthetic. If you choose
to use such a product, useonlythose oils that meet the
American Petroleum Institute (API) and SAE viscosity
standard. Follow the service schedule that describes your
driving type.
Materials Added To Engine Oils
It is not necessary to add any materials to crankcase oils
for most types of vehicle operation. The addition of
materials containing antirust or antiscuff additives can be
beneficial under certain conditions. These include: infre-
quent operation, short trips, and during break-in after a
major engine overhaul. The manufacturer's Engine Oil
Supplement is recommended for these situations.
Disposing of Used Engine Oil
Care should be taken in disposing of used engine oil from
your vehicle. Used oil, indiscriminately discarded, can
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present a problem to the environment. Contact your
dealer, service station, or governmental agency for advice
on how and where used oil can be safely discarded in
your area.
Engine Oil Filter
The engine oil filter should be replaced with a new filter
at every engine oil change.
Engine Oil Filter Selection
All manufacturer's engines have a full-flow type dispos-
able 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. Mopartengine oil filters are high quality oil
filters and are recommended.
Drive Belts Ð Check Condition and Tension
At the mileage shown in the appropriate ªMaintenance
Scheduleº, check the condition of the drive belt for
condition and proper tension. Improper belt tension can
cause belt slippage and failure.
Inspect the drive belt for evidence of cuts, cracks, or
glazing and replace it if there is any sign of damage
which could result in belt failure.
Spark Plugs
Spark plugs must fire properly to assure proper engine
performance and emission control. Install new recom-
mended plugs with the recommended gap at the speci-
fied mileage.
Refer to the ªVehicle Emission Control Informationº label
in the engine compartment for spark plug information.
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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.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.
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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 ex-
haust system. Do not park or operate your vehicle in
areas where your exhaust system can contact any-
thing that can burn.
In unusual situations involving grossly malfunctioning
engine operation, a scorching odor may suggest severe
and abnormal catalyst overheating. If this occurs, stop
the vehicle, turn off the engine and allow it to cool.
Service, including a tune up to manufacturers specifica-
tions, should be obtained immediately.To minimize the possibility of catalytic converter dam-
age:
²Do not shut off the engine or interrupt the ignition
when the transmission is in gear and the vehicle is in
motion.
²Do not try to start the engine by pushing or towing the
vehicle.
²Do not idle the engine with any spark plug wires
disconnected for prolonged period.
Ignition Wiring System and Ignition Timing
The ignition cables should be kept clean and properly
connected. Terminals should be fully seated. Do not
remove the nipple assemblies from the coil towers unless
the nipples are damaged or cable testing shows high
resistance or broken insulation. Refer to the Service
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Manual for the proper procedure to be followed for
checking ignition cable resistance. Cracked, damaged, or
faulty cables should be replaced.
Because of the plastic body shell on your Viper, ignition
cables should be replaced with the specially designed RFI
cables available at your dealer.
Ignition timing cannot be set on this vehicle.
Crankcase Emission Control System
Proper operation of this system depends on freedom
from plugging due to deposits. As vehicle mileage builds
up, the Crankcase Ventilation Valve orifice may accumu-
late deposits. If a valve is not working properly, replace it
with a new orifice. DO NOT ATTEMPT TO CLEAN THE
OLD ORIFICE!
Check the ventilation hose for indication of damage or
plugging deposits. Replace if necessary.
Air Cleaner Filter
Under normal driving conditions, replace the air filter at
the intervals shown on ªMaintenance Schedule Aº. If,
however, you drive the vehicle frequently under dusty or
severe conditions, the filter element should be inspected
periodically and replaced if necessary at the intervals
shown in ªMaintenance Schedule Bº.
WARNING!
The air cleaner can provide protection if the engine
backfires. Do not remove the air cleaner unless such
removal is necessary for repair or maintenance.
Make sure that no one is near the engine compart-
ment before starting the vehicle with the air cleaner
removed. Failure to do so can result in serious
personal injury.
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CAUTION!
It is essential when replacing the cables on the
battery that you attach the positive cable to the
positive post and the negative cable to the negative
post. Battery posts are marked positive (+) and
negative (-) and identified on the battery case. Cable
clamps should be tight on the terminal posts and
free of corrosion. Apply grease to post and clamps
after tightening. If using a ªfast chargerº while the
battery is in the vehicle, disconnect both vehicle
battery cables before connecting the charger to bat-
tery. Do not use a ªfast chargerº to provide starting
voltage.
Battery Save Feature
The Battery Save feature conserves battery power when
storing the vehicle up to 3 months without losing radio
and engine controller memory. This is an alternative to
disconnecting the battery.
NOTE:This vehicle is designed to sit in storage for up
to 30 days on a fully charged battery. If this vehicle is to
be stored for longer than 30 days the following is
recommended:
1. Disconnect the battery
2. Use the battery charger
3. Put the vehicle into Battery Save mode (3 month
charge).
Start the battery save feature by doing the following:
1. Insert the key into the ignition.
158 MAINTAINING YOUR VEHICLE