CAUTION!• During the first 500 miles (805 km) your new
vehicle is driven, do not tow a trailer. Doing so
may damage your axles, driveline and vehicle.
• Limit your speed to 50 mph (80 km/h) during the
first 500 miles (805 km) of towing.
6.7L Diesel Engine
Your Cummins 24 Valve Turbo Diesel engine does not
require a break-in period due to its construction. Normal
operation is allowed, provided the following recommen-
dations are followed:
NOTE: Light duty operation such as light trailer towing
or no load operation, will extend the time before the
engine is at full efficiency and may effect the performance
of the vehicle aftertreatment (exhaust) system. Reduced
fuel economy and power may be seen at this time. • Warm up the engine before placing it under load.
• Do not operate the engine at idle for prolonged
periods.
• Use the appropriate transmission gear to prevent
engine lugging.
• Observe vehicle oil pressure and temperature indica-
tors.
• Check the coolant and oil levels frequently.
• Vary throttle position at highway speeds when carry-
ing or towing significant weight.
Because of the construction of the Cummins Diesel
engine, engine run-in is enhanced by loaded operating
conditions which allow the engine parts to achieve final
finish and fit during the first 6,000 miles (10 000 km). THINGS TO KNOW BEFORE STARTING YOUR VEHICLE 73
2
attempting to start the engine. This can be accomplished
by turning the ignition OFF for at least 5 seconds and
then back ON after the WAIT TO START light has gone
off, but before the engine is started. However, repeated
cycling of the manifold heaters will result in damage to
the heater elements or reduced battery voltage.
NOTE: If multiple pre-heat cycles are used before
starting, additional engine run time may be required to
maintain battery state of charge at a satisfactory level.
• If the engine stalls after the initial start, the ignition
must be turned to the OFF position for at least 5
seconds and then to the ON position to recycle the
manifold heaters.
NOTE: Excessive white smoke and poor engine perfor-
mance will result if manifold heaters are not recycled.
• Heat generated by the manifold heaters dissipates
rapidly in a cold engine. If more than two minutes pass between the time the WAIT TO START light goes
OFF and the engine is started, recycle the manifold
heaters by turning the ignition OFF for at least 5
seconds and then back ON.
• If the vehicle is driven and vehicle speed exceeds 19
mph (31 km) before the manifold heater post-heat
(after start) cycle is complete, the manifold heaters will
shut off.
• If the engine is started before the WAIT TO START
light turns off, the preheat cycle will turn off.
• If the engine is cranked for more than 10 seconds, the
post-heat cycle will turn off.
NOTE: Engine idle speed will automatically increase to
1000 rpm at low coolant temperatures to improve engine
warm-up. STARTING AND OPERATING 255
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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. WARNING!Never add coolant to the radiator when the engine is
overheated. Do not loosen or remove pressure cap to
cool overheated engine! The coolant is under pres-
sure and severe scalding could result.
Cooling System — Drain, Flush and Refill
At the intervals shown on the Maintenance Schedules,
the system should be drained, flushed and refilled. MAINTAINING YOUR VEHICLE 427
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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 before
replacement. To prevent reducing this extended mainte-
nance period, it is important that you use the same
coolant throughout the life of your vehicle. Please review
these recommendations for using Hybrid Organic Addi-
tive Technology (HOAT) coolant.
When adding coolant, a minimum solution of 50% rec-
ommended Mopar Antifreeze/ Coolant 5 Year/100,000
Mile Formula HOAT (Hybrid Organic Additive Technol-
ogy), or equivalent, in water should be used. Use higher
concentrations (not to exceed 70%) if temperatures below
34°F ( 37°C ) are anticipated.
Use only high purity water such as distilled or deionized
water when mixing the water/engine coolant solution. The use of lower quality water will reduce the amount of
corrosion protection in the engine cooling system.
Please note that it is the owner’s responsibility to main-
tain the proper level of protection against freezing ac-
cording to the temperatures occurring in the area where
the vehicle is operated.
NOTE: Mixing coolant types will decrease the life of the
engine coolant and will require more frequent coolant
changes.
Cooling System Pressure Cap
The cap must be fully tightened to prevent loss of
coolant, and to insure that coolant will return to the
radiator from the coolant recovery bottle.
The cap should be inspected and cleaned if there is any
accumulation of foreign material on the sealing surfaces. MAINTAINING YOUR VEHICLE 429
7
WARNING!• The warning words “DO NOT OPEN HOT” on
the cooling system pressure cap are a safety pre-
caution. Never add coolant when the engine is
overheated. Do not loosen or remove the cap to
cool an overheated engine. Heat causes pressure
to build up in the cooling system. To prevent
scalding or injury, do not remove the pressure cap
while the system is hot or under pressure.
• Do not use a pressure cap other than the one
specified for your vehicle. Personal injury or
engine damage may result. Disposal Of Used Engine Coolant
Used ethylene glycol based engine coolant is a regulated
substance requiring proper disposal. Check with your
local authorities to determine the disposal rules for your
community. Do not store ethylene glycol-based engine
coolant in open containers or allow it to remain in
puddles on the ground. Prevent ingestion by animals and
children. If ingested by a child, contact a physician
immediately. Clean up any ground spills immediately.
Coolant Level
The coolant bottle provides a quick visual method for
determining that the coolant level is adequate. With the
engine cold, the level of the coolant in the coolant
recovery bottle should be between the ranges indicated
on the bottle.430 MAINTAINING YOUR VEHICLE
The radiator normally remains completely full, so there is
no need to remove the radiator cap unless checking for
coolant freeze point or replacing coolant. Advise your
service attendant of this. As long as the engine operating
temperature is satisfactory, the coolant bottle need only
be checked once a month.
When additional coolant is needed to maintain the
proper level, it should be added to the coolant bottle. Do
not overfill.
Points To Remember
NOTE: When the vehicle is stopped after a few miles (a
few kilometers) of operation, you may observe vapor
coming from the front of the engine compartment. This is
normally a result of moisture from rain, snow, or high
humidity accumulating on the radiator and being vapor-
ized when the thermostat opens, allowing hot coolant to
enter the radiator. If an examination of your engine compartment shows no
evidence of radiator or hose leaks, the vehicle may be
safely driven. The vapor will soon dissipate.
• Do not overfill the coolant recovery bottle.
• Check 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.
• If 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.
• Maintain coolant concentration at 50% HOAT engine
coolant (minimum) and distilled water for proper
corrosion protection of your engine which contains
aluminum components. MAINTAINING YOUR VEHICLE 431
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take some washer fluid and apply it to a cloth or towel
and wipe clean the wiper blades, this will help blade
performance.
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 (4X4) models only.
• Lubricate Front Drive Shaft Fitting ( 4X4).
Inspection and service should also be performed anytime
a malfunction is observed or suspected. Retain all re-
ceipts. MAINTENANCE SCHEDULES 475
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Miles 82,500 90,000 97,500 100,000 105,000
(Kilometers) (133 000) (145 000) (157 000) (161 000) (169 000)
[Months] [66] [72] [78] [84]
Change engine oil and engine oil filter. X X X X
Lubricate Front Drive Shaft Fitting (4X4). X X X X X
Rotate tires. X X X X X
Check spare tire for proper pressure and correct
stowage. X X XXX
Lubricate outer tie rod ends. X X X X X
Flush and replace engine coolant, if not replaced at
60 mos. X
Check transfer case fluid level (4X4). X
Change front and rear axle fluid (4X4). X X
Change automatic transmission fluid. X
Inspect drive belt, replace as required.* X X
Inspect fan hub. X
Inspect damper. X480 MAINTENANCE SCHEDULES
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