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Change Engine Oil
Road conditions as well as your kind of driving affect the
interval at which your oil should be changed. Check the
following to determine if any apply to you:
²Day or night temperatures are below 32ÉF (0ÉC).
²Stop and go driving.
²Extensive engine idling.
²Driving in dusty conditions
²Short trips of less than 10 miles (16.2 km)
²More than 50% of your driving is at sustained high
speeds during hot weather, above 32ÉC (90ÉF)
²Trailer towing
²Heavy Loading
²Taxi, Police or delivery service (commercial service)
²Off-road or desert operation
²If equipped for and operating with E-85 (ethanol)
fuel.
NOTE:IfANYof these apply to you then change your
engine oil every 3,000 miles (5 000 km) or 3 months,
whichever comes first and follow schedule ªBº of the
9Maintenance Schedules9section of this manual.
If none of these apply to you, then change your engine oil
at every interval shown on schedule9A9of the9Mainte-
nance Schedules9section of this manual.
NOTE:Under no circumstances should oil change in-
tervals exceed 6,000 miles (10 000 km) or 6 months
whichever comes first.
Dusty Conditions
Driving through dust-laden air increases the problems of
keeping abrasive materials out of the engine. Under these
conditions, special attention should be given to the
390 MAINTAINING YOUR VEHICLE
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engine air cleaner, the crankcase inlet air cleaner and the
crankcase ventilation system. Make sure that these units
are clean at all times. This will tend to reduce to a
minimum the amount of abrasive material that may enter
the engine.
Engine Oil Selection
For best performance and maximum protection under all
types of operating conditions, the manufacture only
recommends engine oils that are API certified and meet
the requirements of DaimlerChrysler Material Standard
MS-6395. Use Mopar or an equivalent oil meeting the
specification MS-6395.
American Petroleum Institute (API) Engine Oil
Identification Symbol
There is a symbol to aid you in selecting the proper
engine oil.This symbol means that the oil has
been certified by the American
Petroleum Institute (API). The
manufacture only recommends
API Certified engine oils.
Engine Oil Viscosity (SAE Grade)
For trucks with a 5.7L engine operating under a gross
combined weight rating of 14,000 lbs. or greater, SAE
5W-30 engine oil is recommended for all operating
temperatures. For all other trucks with a 5.7L engine,
operating under a gross weight rating less than 14,000
lbs. SAE 5W-20 engine oil is recommended for all
operating temperatures. This engine oil improves low
temperature starting and vehicle fuel economy. Your
engine oil filler cap also shows the recommended
engine oil viscosity for your vehicle
MAINTAINING YOUR VEHICLE 391
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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
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 ªVehicle Emission Control Informa-
tionº label in the engine compartment.
Spark Plug Wires Ð IF Equipped
The spark plug wires should be kept clean and properly
connected. Terminals should be fully seated. Cracked,
damaged, or faulty wires should be replaced.
Engine Air Cleaner Filter
Under normal driving conditions, replace the air filter at
the intervals shown on Schedule ªAº. If, however, you
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drive the vehicle frequently under dusty or severe con-
ditions, the filter element should be inspected periodi-
cally and replaced if necessary at the intervals shown on
Schedule ªBº.
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.
394 MAINTAINING YOUR VEHICLE
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WARNING!
Battery 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 immediately with
large amounts of water.
Battery 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.
Battery posts, terminals and related accessories con-
tain lead and lead compounds. Wash hands after
handling.
CAUTION!
It is essential when replacing the cables on the
battery that the positive cable is attached to the
positive post and the negative cable is attached to the
negative post. Battery posts are marked (+) positive
and negative (-) and identified on the battery case.
Also, if a ªfast chargerº is used while battery is in
vehicle, disconnect both vehicle battery cables be-
fore connecting the charger to battery. Do not use a
ªfast chargerº to provide starting voltage.
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.
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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.
Refrigerant Recovery and Recycling
R-134a Air Conditioning Refrigerant is a hydrofluorocar-
bon (HFC) that is endorsed by the Environmental Pro-
tection Agency and is an ozone-saving product. How-
ever, the manufacturer recommends that air conditioning
service be performed by dealers or other service facilities
using recovery and recycling equipment.
NOTE:Use only manufacturer approved A/C System
Sealers, Stop Leak Products, Seal Conditioners, Compres-
sor Oil, or Refrigerants.
Power Steering Ð Fluid Check
Checking the power steering fluid level at a defined
service interval is not required. The fluid should only be
checked if a leak is suspected, abnormal noises are
apparent, and/or the system is not functioning as antici-
pated. Coordinate inspection efforts through a certified
DaimlerChrysler Dealership.9
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²Check coolant freeze point in the radiator and in the
coolant recovery bottle. If antifreeze needs to be
added, contents of coolant recovery bottle must also be
protected against freezing.
²If frequent coolant additions are required, or if the
level in the coolant recovery bottle does not drop when
the engine cools, the cooling system should be pres-
sure tested for leaks.
²Maintain coolant concentration at 50% HOAT engine
coolant (minimum) and distilled water for proper
corrosion protection of your engine which contains
aluminum components.
²Make sure that the radiator and coolant recovery
bottle overflow hoses are not kinked or obstructed.
²Keep the front of the radiator clean. If your vehicle is
equipped with air conditioning, keep the front of the
condenser clean, also.
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.
Hoses And Vacuum/Vapor Harnesses
Inspect surfaces of hoses and nylon tubing for evidence
of heat and mechanical damage. Hard or soft spots,
brittle rubber, cracking, tears, cuts, abrasions, and exces-
sive swelling indicate deterioration of the rubber.
Pay particular attention to those hoses nearest to high
heat sources such as the exhaust manifold. Inspect hose
routing to be sure hoses do not come in contact with any
heat source or moving component which may cause heat
damage or mechanical wear.
Insure nylon tubing in these areas has not melted or
collapsed.
408 MAINTAINING YOUR VEHICLE
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can be identified by the Noise Emission Control Label
located in the operator's compartment.Required Maintenance for Noise Control Systems
The following maintenance services must be performed
every 6 months or 6,000 miles (9 600 km), whichever
comes first, to assure proper operation of the noise
control systems. In addition, inspection and service
should be performed anytime a malfunction is observed
or suspected. Proper maintenance of the entire vehicle
will help the effectiveness of the noise control systems.
Air Cleaner Assembly
Inspect air cleaner housing for proper assembly and fit.
Make certain that the air cleaner is properly positioned
and the cover is tight. Check all hoses leading to the
cleaner for tightness. The gasket between the air cleaner
housing and throttle body must be intact and in good
condition. The engine air cleaner filter must also be clean
and serviced according to the instructions outlined in the
appropriate maintenance schedule.
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