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inspect the exhaust system each time the vehicle is raised
for lubrication or oil change. Replace as required.
WARNING!
Exhaust gases can injure or kill. They contain carbon
monoxide (CO) which is colorless and odorless.
Breathing it can make you unconscious and can
eventually poison you. To avoid breathing CO, fol-
low the preceding safety tips.
Exhaust System Rubber Isolator and Loop-Type
Hanger — If Equipped
Inspect surfaces whenever the vehicle is hoisted for
rubber to metal separation or deep cracks. If, however,
excessively deep localized cracks are present, or any part
of the exhaust system abnormally contacts the under-
body hardware, the isolator and/or hanger should be
replaced.
Cooling System
WARNING!
You or others can be badly burned by hot coolant or
steam from your radiator. If you see or hear steam
coming from under the hood, don’t open the hood
until the radiator has had time to cool. Never try to
open a cooling system pressure cap when the radia-
tor is hot.
Engine Coolant Checks
Check the engine coolant (antifreeze) protection every 12
months (before the onset of freezing weather, where
applicable). If coolant is dirty or rusty in appearance, the
system should be drained, flushed and refilled with fresh
coolant. Check the front of the A/C condenser for any
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accumulation of bugs, leaves, etc. If dirty, clean by gently
spraying water from a garden hose vertically down the
face of the condenser.
Check the coolant recovery bottle tubing for brittle rub-
ber, cracking, tears, cuts and tightness of the connection
at the bottle and radiator. Inspect the entire system for
leaks.
Extremely cold ambient temperature may require the
addition of a “winter front” for effective operation of the
cab heating/cooling system. Make certain that a percent-
age of the radiator is exposed for adequate air flow
through the charge air cooler and automatic transmission
oil cooler. The percentage of opening must be increased
with the increasing ambient air temperature and/or
engine load. If the cooling fan can be heard cycling
frequently, increase the size of the opening in the winter
front.Coolant bottle level check
The coolant reserve system provides a quick visual
method of determining that the coolant level is adequate.
With the engine idling, and warmed to the normal
operating temperature, the level of the coolant on the
coolant bottle should be between the fluid level marks.
Check the coolant level whenever the hood is raised.
The radiator normally remains completely full, so there is
no longer a need to remove the coolant pressure cap
except for checking coolant freeze point or replacement
with new antifreeze coolant.
402 MAINTAINING YOUR VEHICLE
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With disc brakes the fluid level can be expected to fall as
the brake linings wear. However, an unexpected drop in
fluid level may be caused by a leak and a system check
should be conducted.
Refer to Fluids, Lubricants and Genuine Parts for the
correct Fluid type.
WARNING!
Use of a brake fluid that may have a lower initial
boiling point, or unidentified as to specification,
may result in sudden brake failure during hard
prolonged braking. You could have an accident.
WARNING!
Overfilling the brake fluid reservoir can result in
spilling brake fluid on hot engine parts and the
brake fluid catching fire.
Use only brake fluid that has been in a tightly closed
container to avoid contamination from foreign matter or
moisture.
CAUTION!
Do not allow a petroleum-base fluid to contaminate
the brake fluid. Seal damage and loss of brake
performance may result.
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Brake Hoses
Inspection should be performed whenever the brake
system is serviced or at intervals specified. Inspect hy-
draulic brake hoses for surface cracking, scuffing or worn
spots. If there is any evidence of cracking, scuffing, or
worn spots, the hose should be replaced immediately!
Eventual deterioration of the hose can take place with
possible burst failure.
Clutch Linkage
If the clutch pedal linkage begins to squeak or grunt, the
clutch pedal pivot bushings should be lubricated. Refer
to Fluids, Lubricants and Genuine Parts for the correct
lubricant type. Multipurpose Grease, NLGI Grade 2 E.P.
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.
Rear Axle And 4x4 Front Driving Axle Fluid Level
For Model 9.25 Front Axles and 10.5”/11.5” Rear Axles
refer to Fluids, Lubricants and Genuine Parts for the
correct lubricant type. For normal service, periodic fluid
level checks are not required. When the vehicle is ser-
viced for other reasons, the exterior surfaces of the axle
assembly should be inspected.
When checking the fluid level, the vehicle should be in a
level position. The fluid level should be 1/4” ± 1/4” (6.4
mm ± 6.4 mm) below the fill hole on the 9.25” Front Axle.
The fluid level should be 3/4” ± 1/4” (19 mm ± 6.4 mm)
below the fill hole on all 10.5” and 1/4” ± 1/4” (6.4 mm
± 6.4 mm) on 11.5” Rear Axles.
Drain And Refill
Vehicles operated in normal service do not have regularly
scheduled oil changes. If fluid has become contaminated
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with water or subjected to severe service, follow the
recommended change intervals in Maintenance Schedule
“B” in Section 8 of this manual.
Lubricant Selection
Refer to Fluids, Lubricants and Genuine Parts for the
correct lubricant type.
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 Differentials in vehicles equipped with
10.5”/11.5” Axles DO NOT REQUIRE any limited slip
oil additive (friction modifiers).
Transfer Case — If Equipped
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.
Lubricant Selection
Refer to Fluids, Lubricants and Genuine Parts for the
correct lubricant type.
Manual Transmission — If Equipped
Fluid Level Check
This fluid level can be checked by removing the filler
plug. If the level of the lubricant is more than 1/4” 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.
412 MAINTAINING YOUR VEHICLE
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•Off-road or desert operation.
•Extensive operation at high engine speeds (greater
than 2900 rpm) and loads (greater than 70% throttle).
NOTE: Most vehicles are operated under the conditions
listed for Schedule B.
NOTE: IfANY of these apply to you then change your
coolant every 101,250 miles (162 000 km) or 60 months,
whichever comes first and follow schedule “B” of the
Maintenance Schedules section of this manual.
Second is Schedule “A”. It is for vehicles that are not
operated under any of the conditions listed under Sched-
ule B.
Use the schedule that best describes your driving condi-
tions. Where time and mileage are listed, follow the
interval that occurs first.
CAUTION!
Failure to perform the required maintenance items
may result in damage to the vehicle.
At Each Stop for Fuel
•Check the engine oil level about 15 minutes after a
fully warmed engine is shut off. Checking the oil level
while the vehicle is on level ground will improve the
accuracy of the oil level reading. Add oil only when
the level is at or below the ADD or MIN mark.
•Check the windshield washer solvent and add if
required. When refilling the washer fluid reservoir,
take some washer fluid and apply it to a cloth or towel
and wipe clean the wiper blades, this will help blade
performance.
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Once a Month
•Check tire pressure and look for unusual wear or
damage.
•Inspect the batteries and clean and tighten the termi-
nals as required.
•Check the fluid levels of coolant reservoir, brake
master cylinder, and transmission and transfer case (if
equipped), add as needed.
•Check Filter Minder™. Replace air cleaner filter
element if necessary.
•Check all lights and all other electrical items for correct
operation.
•Drain water from the fuel filter. At Each Oil Change
•Change the engine oil filter.
•Inspect the exhaust system.
•Inspect the brake hoses.
•Inspect the U-Joints ( if equipped) and front suspen-
sion components.
•Check the automatic transmission fluid level.
•Check the manual transmission fluid level.
•Check the coolant level, hoses, and clamps.
•Lubricate outer tie rod ends.
•Lubricate Front Drive Shaft Fittin
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Miles 3,750 7,500 11,250 15,000 18,750
(Kilometers) (6 000) (12 000) (18 000) (24 000) (30 000)
Change engine oil and engine oil filter. X X
Lubricate Front Drive Shaft Fitting (2500/3500,
4X4). X X XXX
Rotate tires. X X
Check spare tire for proper pressure and correct
stowage. XX
Lubricate outer tie rod ends 2500/3500 (4X4) mod-
els. XX
Replace fuel filter element. X
Change rear axle fluid. X
Change front axle fluid (4X4). X
Inspect brake linings. X
Inspect and adjust parking brake if necessary. X
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