STARTING PROCEDURES
Operating precautions
•Always shift to a lower gear at high altitudes to prevent engine
smoking.
•Avoid extended and unnecessary idling.
Diesel engine vapors are combustible. Do not operate the engine
in an enclosed area. These vapors can be sucked through the air
intake system and cause an explosion which may result in severe
bodily injury and extensive property damage.
Starting the engine
1. Ensure headlamps and all accessories are turned off, the parking
brake is applied and the transmission is in the neutral position (or P
[Park] for Allison 2400 transmissions).
If your vehicle is equipped with an
air intake heater, the heater will
activate in cooler weather. If the
WAIT TO START light illuminates,
do notcrank the engine until the
light goes off.
If equipped with an air intake heater, DO NOT use ether or any
other starting fluids. The use of starting fluids (ether) in an
engine equipped with an air intake heater could cause an explosion
and result in property damage and/or personal injury.
2. Do not depress the accelerator during starting the engine.
3. Start the engine.
If the engine does not start after 30 seconds of cranking, allow two
minutes for the starter to cool before trying again. Excessive cranking
may damage the starter.
WAIT
TO
START
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•If your vehicle is equipped with a water-fuel separator, drain it daily.
Fill the fuel tank at the end of daily operation to prevent condensation
in the fuel system.
•Make sure you use proper cold weather engine oil and that it is at its
proper level.
•At temperatures of–4°F(–20°C) or below, it is recommended that you
use a crankcase-mounted coolant heater to improve cold engine
starting.
•If operating in arctic temperatures of -20°F(–29°C) or lower, consult
your truck dealer for information about special cold weather
equipment and precautions.
Note:Idling in cold weather will not heat the engine to its normal
operating temperature. Long periods of idling in cold weather can cause
a buildup of heavy deposits of carbon and rust on valve stems causing
them to stick which, in turn, can cause valvetrain damage.
The following cold weather idling guidelines must be followed:
•Avoid idling the engine for more than 10 minutes at a time.
•Use a minimum of 45 Cetane Diesel fuel or use Cetane Index
improvers from a reputable manufacturer.
•Maintain a minimum idle of 1250 RPM by using the hand throttle.
Always make sure that the parking brake is applied and the
transmission is in neutral before applying the hand throttle.
•Maintain the engine cooling system properly.
•Do not shut the engine down after an extensive idling period (10
minutes or more). Drive the vehicle under load for several miles at
normal operating temperatures to burn off any accumulated carbon
and varnish.
•Consider using an engine block heater, approved winter fronts and/or
radiator shutters where conditions warrant.
Winter fronts
The use of winter fronts, or other air-restrictive devices mounted in front
of the radiator on vehicles with chassis-mounted charge air coolers, are
not recommended unless extremely cold weather conditions exist. Air
flow restriction can cause high exhaust temperatures, power loss,
excessive fan usage and a reduction in fuel economy. If you must use a
winter front, the device should have a permanent opening of at least 120
sq in. (774 sq. cm) directly in line with the fan hub.
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Hot weather operation
•Keep the engine cooling system filled with a clean, permanent coolant
solution to protect against damage from overheating.
•Fill the fuel tank at the end of daily operation to prevent condensation
in the fuel system.
•Keep external surfaces of the engine, radiator, charge air cooler, A/C
condenser and accessories clean to avoid dirt build-up.
Above normal coolant temperatures could be experienced while driving
in a transmission gear ratio which lugs the engine. To correct this
problem, engine speed should be increased by downshifting in to the
next lower gear to increase engine RPM.
Starting a turbocharged engine with the vehicle on a steep grade
When starting a diesel engine when the loaded vehicle is on a grade, the
engine RPM will start to fall slightly when the clutch is engaged; do not
disengage the clutch and try to increase engine RPM as this may damage
driveline components. The engine will recover as the vehicle begins
moving.
Engine shutdown
Allow the engine to idle for three to five minutes before shutting it
down. The larger the engine, the greater the need for this idling period.
However, do not let the engine idle for more than 10 minutes.
Engine automatic shutdown warning light or chime (if equipped)
Your vehicle may be equipped with an automatic shutdown feature that
stops the engine in the event of high coolant temperature, low engine oil
pressure or low engine coolant level. A warning light in the instrument
cluster and a warning chime will indicate high engine coolant
temperature or low engine oil pressure. If the temperature and/or
pressure becomes too high or too low, the engine will automatically shut
down.
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Vehicles that are equipped with an
override feature, allow the operator
to restart the engine so the vehicle
can be moved; the engine should
not be operated any longer than
necessary. A decal located in front
of the operator provides instructions
on how the override should be
operated.
Do not attempt to use this restarting feature to drive the vehicle very far
as serious engine damage could result.
In the event of engine shutdown, make sure the vehicle is safely
off the road and the problem is remedied prior to returning to
the road. Failure to remove the vehicle from the road could result in
an accident, causing serious injury or death.
GENERAL OPERATING INSTRUCTIONS
•Start the vehicle in motion by using the highest gear speed in the
transmission that will let the engine easily start the load without
slipping the clutch.
•Accelerate smoothly and evenly; rapid acceleration increases fuel
consumption without increasing engine performance.
•When approaching a hill, depress the accelerator smoothly to start the
incline at full power, then shift down as needed to maintain vehicle
speed.
•When going down a hill, or long steep grades, prevent over-speeding
of the engine. The engine governor has no control over engine speed
when it is being pushed by a loaded vehicle.
•Operate in a gear that will permit an engine speed not in excess of the
maximum governed speed or high-idle RPM (no load).
•Normally, choose the same gear to descend the hill that you would use
to ascend the hill.
All vehicles have blind spots. To reduce the risk of severe injury
or property damage, never move your vehicle to the side or rear
or change lanes without being sure your way is clear on both sides and
to your rear.
SHDN
OVRD
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Backing up
To reduce the risk of the possibility of personal injury while
backing the vehicle, always be sure your vehicle’s path is clear.
Before backing your vehicle, be sure you can do so safely. If anything
behind the cab limits your view, do not rely on mirrors alone to assure
that your intended path is clear. If other people are in the vicinity, have
someone standing well behind your vehicle and outside of your intended
path (visible through an exterior mirror) guide you as you back up.
Although OSHA or some governmental regulations may require the use
of an electrical or mechanical back-up alarm to warn bystanders, such an
alarm does not assure that the intended path is clear. When in doubt, get
out of the vehicle and visually check the intended path is clear; back-up
slowly as to allow others time to move, if necessary.
If an electrical back-up alarm is installed, it should be connected to the
back-up lamp circuit.
Parking your vehicle
Always use the parking brake. When parking on a grade, block the
wheels and turn the front wheels to one side so that if the vehicle rolls,
the front tires will act against the curb to stop the vehicle. The front
wheels will be more effective at stopping a rolling vehicle than the rear
wheels.
When parking your vehicle, do not leave the transmission in
gear; if the key is in the ON position and the vehicle rolls, the
engine could start. Failure to follow these instructions could result in
an unattended vehicle moving, possibly causing personal injury or
property damage.
Driving through water
If driving through deep or standing water is unavoidable, proceed very
slowly especially if the depth is not known. Never drive through water
that is higher than the bottom of the hubs (for trucks) or the bottom of
the wheel rims (for cars). Traction or brake capability may be limited
and your vehicle may stall. Water may also enter your engine’s air intake
and severely damage your engine, drive axles or the transmisison
(through the breather ports).
Once through the water, always dry the brakes by moving your vehicle
slowly while applying light pressure on the brake pedal. Wet brakes do
not stop the vehicle as quickly as dry brakes.
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Parking brake
Apply the parking brake whenever
the vehicle is parked. To set the
parking brake, pull handle up until it
snaps into the locked position.
When the parking brake is out of
adjustment, seek service
immediately.
The parking BRAKE warning lamp
in the instrument cluster illuminates
and remains illuminated (when the
ignition is turned ON) until the
parking brake is released.
Do not use the gearshift selector in place of the parking brake.
Always set the parking brake fully AND make sure the gearshift
selector is in R (Reverse) for vehicles equipped with manual
transmission, P (Park)(if equipped)or N (Neutral) for vehicles with
automatic transmission. Use of wheel chocks is also recommended in
hilly or off-road usage.
Unexpected and possible sudden vehicle movement may occur if
these precautions are not taken.
P
BRAKE
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Releasing the parking brake
Note:Read and understand the following steps and perform them
whenever you prepare to drive the vehicle.
Note:The parking brake will not disengage unless sufficient system air
pressure is available.
For vehicles with automatic transmissions - dash-mounted push
button (Allison MD) and steering column-mounted (Allison 2000
and 2400) gear selection:
1. With the engine running, depress and hold the service brake pedal.
2. Wait until system air pressure is above 100 psi.
3. Select the appropriate drive gear.
4. Push the yellow, dash-mounted parking brake knob.
For vehicles with manual transmissions - (TTC 7–speed,
Eaton/Fuller 5–speed, 6–speed and 10–speed):
1. With the engine running, depress and hold the service brake pedal.
2. Wait until system air pressure is above 100 psi.
3. Depress and hold the clutch pedal.
4. Select the appropriate drive gear.
5. Push the yellow, dash-mounted parking brake knob.
Hold the brake pedal down while moving the gearshift lever from
position to position. If the brake pedal is not held down, the
vehicle may move unexpectedly resulting in property damage, personal
injury or death.
Parking brake light illumination due to low air pressure
If at any time during vehicle operation air pressure is too low, the
parking brake may apply and the parking brake light will turn on.
If the parking brake is applied due to low air pressure, immediate service
is required to the parking brake system.
Parking brake warning system
If the park brake light blinks and a chime sounds when pulling the yellow
control knob out, this indicates the parking brake is not functioning
properly; seek service for the parking brake immediately.
The light will blink and the chime will sound until the yellow control
knob is pushed in or approximately eight minutes have passed. If the
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Cam brakes - automatic slack adjusters
Standard air brakes (cam) are
equipped with automatic brake
adjusters. Automatic adjustment
occurs during brake applications.
Inspect brakes for proper
adjustment at the intervals listed in
the vehicle Service Maintenance
Guide.
Emergency air brake
All vehicles are equipped with a dual brake system. In the unlikely event
of a failure of one system, the second system will function for emergency
stopping. These systems are all controlled by the brake pedal in the
same manner as for normal stops.
Do not continue to operate the vehicle with a failure of one of
the systems. Take the vehicle to your dealer for service
immediately.
Parking brake
Do not use the gearshift selector in place of the parking brake;
unexpected and possible sudden vehicle movement may occur if
these precautions are not taken. Always set the parking brake fully
AND make sure the gearshift selector is in R (Reverse) for vehicles
equipped with manual transmission, N (Neutral) for vehicles with
automatic transmission (except Allison 2400 transmission) or P (Park)
(Allison 2400 transmission).
If the service brakes should fail to operate while the vehicle is in motion,
you can make an emergency stop with the parking brake. Since the
parking brake only applies stopping power to the rear wheels, the
vehicle’s stopping distance will greatly increase and the handling of the
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