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NOTE:During snowplow usage on vehicles equipped
with an overhead console module, the outside tempera-
ture display will show higher temperatures than the
outside ambient temperature. The higher displayed tem-
perature is due to blocked or reduced airflow to the
underhood ambient temperature sensor by the snow-
plow. This is common, and outside temperature display
operation will return to normal when the snowplow is
removed.
General Maintenance
Snowplows should be maintained in accordance with the
plow manufacturer's instructions. Whenever the plow is
disconnected from the vehicle, coat the exposed angling
cylinder rods with chassis lubricant. The lift cylinder
should be extended upward and chassis lubricant ap-
plied to the lift rod. The hydraulic hoses interconnect to
keep the couplers clean.Keep all snowplow electrical connections and battery
terminals clean and free of corrosion.
When plowing snow, to avoid transmission and driv-
etrain damage, the following precautions should be ob-
served.
²Operate with transfer case in 4L when plowing small
or congested areas where speeds are not likely to
exceed 15 mph (24 km/h). At higher speeds operate in
4H.
²Do not shift the transmission unless the engine has
returned to idle and wheels have stopped. Make a
practice of stepping on the brake pedal before shifting
the transmission between forward and reverse.
NOTE:Change the automatic transmission fluid and
filter(s), refer to ªMaintenance Scheduleº in Section 8.
STARTING AND OPERATING 405
5
Page 443 of 554
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
Page 444 of 554

NMaintenance-Free Battery................457
NAir Conditioner Maintenance.............459
NPower Steering Ð Fluid Check............460
NFront Suspension Ball Joints..............460
NSteering Linkage Ð Inspection............461
NHalf-Shaft Constant Velocity Joints.........461
NFront Prop Shaft Lubrication Ð
2500/3500 (4X4) Models................462
NBody Lubrication.....................462
NWindshield Wiper Blades................463
NWindshield Washers...................463
NExhaust System......................464NCooling System.......................465
NHoses And Vacuum/Vapor Harnesses.......470
NFuel System Connections................471
NBrake System........................471
NClutch Hydraulic System................474
NClutch Linkage.......................474
NRear Axle And 4X4 Front Driving Axle
Fluid Level..........................474
NTransfer Case........................475
NManual Transmission..................476
NAutomatic Transmission................476
NFront And Rear Wheel Bearings...........479
442 MAINTAINING YOUR VEHICLE
Page 445 of 554

NNoise Control System Required Maintenance &
Warranty For 3500 2-Wheel Drive And 4-Wheel
Drive Models Over 10,000 Lbs. (4 535 Kg)
Gross Vehicle Weight Rating..............480
NAppearance Care And Protection From
Corrosion...........................484
mFuses (Integrated Power Module)...........489
mVehicle Storage........................493
mReplacement Light Bulbs.................494
mBulb Replacement......................495
NHeadlight (Halogen)/Front Park And Turn
Lights.............................495
NFog Lights..........................498
NTail, Stop, Turn And Backup Lights.........499NCenter High-Mounted Stoplight (CHMSL)
With Cargo Light.....................502
NCab Top Clearance Lights Ð If Equipped....503
NTailgate ID Lights (Dual Rear Wheels) Ð
If Equipped.........................505
NRear Light Bar ID Marker (Dual Rear Wheel) Ð
If Equipped.........................506
NSide Marker Lights (Dual Rear Wheels)......507
mFluids And Capacities...................508
mFluids, Lubricants And Genuine Parts........510
NEngine.............................510
NChassis............................511
MAINTAINING YOUR VEHICLE 443
7
Page 450 of 554

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.
448 MAINTAINING YOUR VEHICLE
Page 451 of 554

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.
MAINTAINING YOUR VEHICLE 449
7
Page 452 of 554

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.
450 MAINTAINING YOUR VEHICLE
Page 454 of 554
Change Engine Oil
Follow the Maintenance Schedule for recommended en-
gine oil change intervals.
Engine Oil Selection
For best performance and maximum protection under all
types of operating conditions, the manufacturer only
recommends engine oils that are API-certified and meet
the requirements of DaimlerChrysler Material Standard
MS-6395.
American Petroleum Institute (API) Engine Oil
Identification Symbol
This symbol means that the oil has
been certified by the American
Petroleum Institute (API). The
manufacturer only recommends
API-Certified engine oils.
Engine Oil Viscosity (SAE Grade)
SAE 5W-20 engine oil is recommended for all operating
temperatures. This engine oil improves low temperature
starting and vehicle fuel economy. The engine oil filler
cap also shows the recommended engine oil viscosity for
your engine. For information on engine oil filler cap
location, refer to the ªEngine Compartmentº illustration
in this section.
452 MAINTAINING YOUR VEHICLE