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CAUTION!
²Mixing of coolants other than specified HOAT
engine coolants, may result in engine damage and
may decrease corrosion protection. If a non-HOAT
coolant is introduced into the cooling system in an
emergency, it should be replaced with the speci-
fied coolant as soon as possible.
²Do not use plain water alone or alcohol-base
engine coolant (antifreeze) products. Do not use
additional rust inhibitors or antirust products, as
they may not be compatible with the radiator
engine coolant and may plug the radiator.
²This vehicle has not been designed for use with
Propylene Glycol based coolants. Use of Propy-
lene Glycol based coolants is not recommended.
Adding Coolant
Your vehicle has been built with an improved engine
coolant that allows extended maintenance intervals. This
coolant can be used up to 5 Years or 100,000 miles (160
000 km) before replacement. To prevent reducing this
extended maintenance period, it is important that you
use the same coolant throughout the life of your vehicle.
Please review these recommendations for using Hybrid
Organic Additive Technology (HOAT) coolant. When
adding coolant:
²The manufacturer recommends using Mopart
Antifreeze/Coolant 5 Year/100,000 Mile Formula
HOAT (Hybrid Organic Additive Technology).
²Mix a minimum solution of 50% HOAT engine coolant
and distilled water. Use higher concentrations (not to
exceed 70%) if temperatures below -34ÉF (-37ÉC) are
anticipated.
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Ensure nylon tubing in these areas has not melted or
collapsed.
Inspect all hose connections such as clamps and cou-
plings to make sure they are secure and no leaks are
present.
Components should be replaced immediately if there is
any evidence of wear or damage that could cause failure.
Fuel System Connections
Electronic Fuel Injection high pressure fuel systems are
designed with tubes and special connects, connections
and clamps which have unique material characteristics to
provide adequate sealing and resist attack by deterio-
rated gasoline.
You are urged to use only the manufacture's specified
tubes, connections and clamps, or their equivalent in
material and specification, in any fuel system servicing.
Brake System
Power Disc Brakes (Front and Rear)
Disc brakes do not require adjustment; however, several
hard stops during the break-in period are recommended
to seat the linings and wear off any foreign material.
Brake and Power Steering Hoses
When the vehicle is serviced for scheduled maintenance,
inspect surface of hoses and nylon tubing for evidence of
heat and mechanical damage. Hard and brittle rubber,
cracking, tears, cuts, abrasion, and excessive swelling
indicate deterioration of the rubber. Particular attention
should be made to examining those hose surfaces nearest
to high heat sources, such as the exhaust manifold.
Ensure nylon tubing in these areas has not melted or
collapsed.
MAINTAINING YOUR VEHICLE 471
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Page 476 of 554

Clutch Hydraulic System
The clutch hydraulic system is a sealed maintenance-free
system. In the event of leakage or other malfunction, the
system must be replaced.
Clutch Linkage
If the clutch pedal linkage begins to squeak or grunt, the
clutch pedal pivot bushings should be lubricated. For the
correct lubricant type, refer to ªFluids, Lubricants and
Genuine Partsº in this Section.
Rear Axle And 4x4 Front Driving Axle Fluid Level
For the correct Fluid type, refer to ªFluids, Lubricants
and Genuine Partsº in this Section. For normal service,
periodic fluid level checks are not required. When the
vehicle is serviced for other reasons the exterior surfaces
of the axle assembly should be inspected. If gear oil
leakage is suspected inspect the fluid level.This inspection should be made with the vehicle in a level
position. The fluid level should be even with the bottom
of the fill hole for the Manufacturer's C205F HD front
axles. The fluid level should be 5/8 in (16 mm) below the
fill hole on 9 1/4 in manufacturer's rear axles.
For all 2500/3500 Model axles, the fluid level should be
1/4º 1/4 in(6.4 mm 6.4 mm) below the fill hole on the
9.25 in front and 3/4 in 1/4 in (19 mm 6.4 mm) on
10.5 in rear axles. The 11.5 in rear axle level should be 1/4
in 1/4 in (6.4 mm 6.4 mm) below the fill hole.Drain and Refill
Follow the Maintenance Schedule for recommended
front and rear axle fluid change intervals.
Lubricant Selection
For the correct fluid type, refer to ªFluids, Lubricants and
Genuine Partsº in this Section.
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NOTE:The presence of water in the gear lubricant will
result in corrosion and possible failure of differential
components. Operation of the vehicle in water, as may be
encountered in some off-highway types of service, will
require draining and refilling the axle to avoid damage.
Limited-Slip Differentialsin 1500 Model vehicles re-
quire that 4 oz. (118 ml) Mopartlimited slip additive be
added to the gear lubricant. Refer to Fluids, Lubricants
and Genuine Parts for correct fluid type. The Mopart
Limited Slip Additive should be added to the gear
lubricant whenever a fluid change is made.
2500/3500 Model AxlesDO NOT REQUIREany limited
slip oil additive (friction modifiers).Transfer Case
Drain And Refill
Follow the Maintenance Schedule for recommended
transfer case fluid change intervals.
Lubricant Selection
For the correct Fluid type, refer to ªFluids, Lubricants
and Genuine Partsº in this Section.
Fluid Level Check
This fluid level can be checked by removing the filler
plug. The fluid level should be to the bottom edge of the
filler plug hole with the vehicle in a level position.
MAINTAINING YOUR VEHICLE 475
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Page 478 of 554

Manual Transmission
Lubricant Selection G238 (6-Speed Manual
Transmission Ð If Equipped)
This transmission is filled with manual transmission
fluid at the factory. This fluid does not require periodic
changing. If it is necessary to add or change fluid in this
transmission refer to Fluids, Lubricants and Genuine
Parts for correct fluid type. This is the only lubricant
recommended for use in the Getrag 238 transmission.
Lubricant Selection G56 (6-Speed Manual
Transmission Ð If Equipped)
Follow the Maintenance Schedule for recommended
transmission fluid change intervals. If it is necessary to
add or change fluid in this transmission refer to ªFluids,
Lubricants and Genuine Partsº for correct fluid type. This
is the only lubricant recommended for use in the G56
transmission.
Fluid Level Check ± All Manual Transmissions
This fluid level can be checked by removing the fill plug.
If the level of the lubricant is more than 1/4 in(6.4 mm)
below the bottom of the filler hole while the vehicle is on
level ground, enough lubricant should be added to bring
the level to the bottom of the filler hole.
Automatic Transmission
Selection Of Lubricant
It is important that the proper lubricant is used in the
transmission to assure optimum transmission perfor-
mance. Use only manufacturer 's recommended transmis-
sion fluid; refer to ªFluids, Lubricants and Genuine
Partsº in this section for correct fluid type. It is important
that the transmission fluid be maintained at the pre-
scribed level using the recommended fluid.
476 MAINTAINING YOUR VEHICLE
Page 481 of 554

7. Check for leaks. Release parking brake.
To prevent dirt and water from entering the transmission
after checking or replenishing fluid, make certain that the
dipstick cap is properly reseated. It is normal for the
dipstick cap to spring back slightly from its fully seated
position, as long as its seal remains engaged in the
dipstick tube.
Automatic Transmission Fluid and Filter Change
Follow the Maintenance Schedule for recommended
transmission fluid and filter change intervals.
NOTE:If the transmission is disassembled for any
reason, the fluid and filter(s) should be changed.
It is important that proper lubricant is used in the
transmission. For the correct Fluid type, refer to ªFluids,
Lubricants and Genuine Partsº in this Section.
Special Additives
Automatic Transmission Fluid (ATF) is an engineered
product and its performance may be impaired by supple-
mental additives. Therefore, do not add any fluid addi-
tives to the transmission. The only exception to this
policy is the use of special dyes to aid in detecting fluid
leaks. In addition, avoid using transmission sealers as
they may adversely affect seals.
Front and Rear Wheel Bearings
Front Wheel Bearings
Front wheel bearings for all vehicles are sealed-for-life.
They do not require greasing or seal replacement. In
some instances, these bearings will ªpurgeº excess grease
and the bearing will look slightly wet. This is normal.
Periodic inspection for excess play is recommended.
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Page 482 of 554
Rear Wheel Bearings Ð Manufacturer's Axles
These bearings are normally considered permanently
lubricated. Cleaning and repacking is required only
when axle shafts are removed or in case of extreme water
or dust contamination.
Noise 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.
All vehicles built over 10,000 lbs (4 535 kg) Gross Vehicle
Weight Rating and manufactured for sale and use in the
United States are required to comply with the Federal
Government's Exterior Noise Regulations. These vehiclescan be identified by the Noise Emission Control Label
located in the operator's compartment.
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Required Maintenance for Noise Control Systems
The following maintenance services must be performed
every six months or 6,000 mi (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.
Tampering with Noise Control System Prohibited
Federal law prohibits the following acts or the causing
thereof: (1) the removal or rendering inoperative by any
person, other than for purposes of maintenance, repair, or
replacement, of any device or element of design incorpo-
rated into any new vehicle for the purpose of noise
control prior to its sale or delivery to the ultimate
purchaser or while it is in use, or (2) the use of the vehicle
after such device or element of design has been removed
or rendered inoperative by any person.
Among those acts presumed to constitute tampering are
the acts listed below.
AIR CLEANER
²Removal of the air cleaner.
²Inverting the air cleaner lid.
²Removal of the air ducting.
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