Page 68 of 448

•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).
CAUTION!
•During the first 500 miles (805 km) your new
vehicle is driven, do not tow a trailer. Doing so
may damage your vehicle.
•Limit your speed to 50 mph (80 km/h) during the
first 500 miles (805 km) of towing.
SAFETY TIPS
Transporting Passengers
This vehicle is designed to carry passengers in the cab
only. For safety reasons, NEVER TRANSPORT PASSEN-
GERS IN THE CARGO AREA.
WARNING!
It is extremely dangerous to ride in a cargo area,
inside or outside of a vehicle. In a collision, people
riding in these areas are more likely to be seriously
injured or killed.
Do not allow people to ride in any area of your
vehicle that is not equipped with seats and seat belts.
Be sure everyone in your vehicle is in a seat and
using a seat belt properly.
68 THINGS TO KNOW BEFORE STARTING YOUR VEHICLE
Page 227 of 448

•After the WAIT TO START light goes off, turn the
ignition key to START. Do not press the accelerator
during starting.
•Check to see that there is oil pressure.
•Allow the engine to idle at fast idle for about three
minutes until the manifold heaters have completed
the post-heat cycle.
•Release the parking brake and drive.
NOTE:Engine idle speed will automatically increase to
1000 rpm at low coolant temperatures to improve engine
warm-up.
NOTE:If the engine stalls or if the ignition switch is left
On for more than 2 minutes after the WAIT TO START
light goes out, reset the grid heaters by turning the
ignition switch to Off for at least 5 seconds and then back
On. Repeat steps 3 through 7 of the normal starting
procedure.
For Extremely Cold Weather Starting — Engine
Manifold Air Temperature Below 0°F (- 18°C)
In extremely cold weather below 0°F (- 18°C) it may be
beneficial to cycle the manifold heaters twice before
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.
STARTING AND OPERATING 227
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Page 344 of 448

Never operate the engine with oil level below the “ADD”
mark or above the upper “SAFE” mark.
Change Engine Oil
CAUTION!
Overfilling or underfilling the crankcase will cause
oil aeration or loss of oil pressure. This could dam-
age your engine.
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:
•Frequent short trips where the engine does not achieve
full operating temperature (operating temperature de-
fined as 190° F (66° C) coolant temperature).
•Extensive engine idling (over 10 minutes per hour of
operation) at ambient temperatures less than 32° F (0°
C).
•Driving in dusty conditions.
•Frequent trailer towing.
•Taxi, police, or delivery service (commercial service).
•Off-road or desert operation.
•Extensive operation at high engine speeds (greater
than 2900 rpm) and loads (greater than 70% throttle).
IfANYof these apply to you, then change your engine oil
at every interval shown in scheduleBof theMainte-
nance Schedulessection of this manual.
If none of these apply to you, then change your engine oil
at every interval shown on scheduleAof theMainte-
nance Schedulessection of this manual.
344 MAINTAINING YOUR VEHICLE
Page 361 of 448

of the exhaust system abnormally contacts the under-
body hardware, the isolator and/or hanger should be
replaced.
Cooling System
Cooling System Maintenance
At the intervals shown in the Maintenance Schedules
Section of the manual, the system should be drained,
flushed and filled.
Inspection
Check 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 as specified.
Inspect the entire cooling system for leaks. Check the face
of the radiator for any accumulation of bugs, leaves, or
other foreign matter. If dirty, clean the radiator core witha garden hose. With the engine OFF, gently spray water
from the back of the radiator core. Check coolant bottle
tube for condition and tightness of connections at coolant
bottle and radiator.
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
MAINTAINING YOUR VEHICLE 361
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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.
Drain, Flush And Refill
At intervals shown on the Maintenance Schedules, the
system should be drained, flushed and refilled. Refer to
your dealer or consult a service manual for proper
procedures.
Adding Coolant
When adding coolant, or refilling the system, a minimum
solution of 50% recommended HOAT ethylene glycol
engine coolant (antifreeze) and distilled water should be
used. Use higher concentrations (not to exceed 70%) if
temperatures below34°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.
362 MAINTAINING YOUR VEHICLE
Page 363 of 448

NOTE:It is the owner’s responsibility to maintain the
proper level of protection against freezing according 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.
When additional coolant is needed to maintain the
proper level, add the recommended concentration of
antifreeze and water to the overflow bottle. Do not
overfill.
NOTE:Failure to follow the antifreeze concentration
and replacement recommendations, or failure to use
antifreeze formulated to prevent corrosion of all cooling
system metals, may result in radiator plugging, overheat-
ing, or cooling system leaks such as in core hole plugs.WARNING!
Never add coolant to the radiator when the engine is
overheated. Do not loosen or remove pressure cap to
cool an overheated engine. The coolant is under
pressure and severe scalding could result.
Recommended Engine Coolant
Refer to Recommended Fluids, Lubricants and Genuine
Parts for the correct Fluid type.
MAINTAINING YOUR VEHICLE 363
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Page 403 of 448

•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 ScheduleB.
NOTE:IfANYof these apply to you then change your
coolant every 102,000 miles (163 000 km) or 60 months,
whichever comes first and follow schedule “B” of the
Maintenance Schedulessection of this manual.
Second is Schedule“A”. It is for vehicles that are not
operated under any of the conditions listed under Sched-
uleB.
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.
•Drain water from the fuel filter.
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Page 404 of 448
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.At Each Oil Change
•Change the engine oil filter.
•Inspect the exhaust system.
•Inspect the brake hoses.
•Inspect the CV 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.
404 MAINTENANCE SCHEDULES
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